docs: Update contributor name to Aakash Suresh

Use actual name instead of GitHub username for better recognition.

.gitattributes

@@ -1 +0,0 @@
-paper_plot/data/big_graph_degree_data.npz filter=lfs diff=lfs merge=lfs -text

.github/ISSUE_TEMPLATE/bug_report.yml

@@ -0,0 +1,50 @@
+name: Bug Report
+description: Report a bug in LEANN
+labels: ["bug"]
+
+body:
+  - type: textarea
+    id: description
+    attributes:
+      label: What happened?
+      description: A clear description of the bug
+    validations:
+      required: true
+
+  - type: textarea
+    id: reproduce
+    attributes:
+      label: How to reproduce
+      placeholder: |
+        1. Install with...
+        2. Run command...
+        3. See error
+    validations:
+      required: true
+
+  - type: textarea
+    id: error
+    attributes:
+      label: Error message
+      description: Paste any error messages
+      render: shell
+
+  - type: input
+    id: version
+    attributes:
+      label: LEANN Version
+      placeholder: "0.1.0"
+    validations:
+      required: true
+
+  - type: dropdown
+    id: os
+    attributes:
+      label: Operating System
+      options:
+        - macOS
+        - Linux
+        - Windows
+        - Docker
+    validations:
+      required: true

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,8 @@
+blank_issues_enabled: true
+contact_links:
+  - name: Documentation
+    url: https://github.com/LEANN-RAG/LEANN-RAG/tree/main/docs
+    about: Read the docs first
+  - name: Discussions
+    url: https://github.com/LEANN-RAG/LEANN-RAG/discussions
+    about: Ask questions and share ideas

.github/ISSUE_TEMPLATE/feature_request.yml

@@ -0,0 +1,27 @@
+name: Feature Request
+description: Suggest a new feature for LEANN
+labels: ["enhancement"]
+
+body:
+  - type: textarea
+    id: problem
+    attributes:
+      label: What problem does this solve?
+      description: Describe the problem or need
+    validations:
+      required: true
+
+  - type: textarea
+    id: solution
+    attributes:
+      label: Proposed solution
+      description: How would you like this to work?
+    validations:
+      required: true
+
+  - type: textarea
+    id: example
+    attributes:
+      label: Example usage
+      description: Show how the API might look
+      render: python

.github/pull_request_template.md

@@ -0,0 +1,13 @@
+## What does this PR do?
+
+<!-- Brief description of your changes -->
+
+## Related Issues
+
+Fixes #
+
+## Checklist
+
+- [ ] Tests pass (`uv run pytest`)
+- [ ] Code formatted (`ruff format` and `ruff check`)
+- [ ] Pre-commit hooks pass (`pre-commit run --all-files`)

.github/workflows/build-and-publish.yml

@@ -5,6 +5,7 @@ on:
     branches: [ main ]
   pull_request:
     branches: [ main ]
+  workflow_dispatch:
 
 jobs:
   build:

.github/workflows/build-reusable.yml

@@ -54,20 +54,51 @@ jobs:
             python: '3.12'
           - os: ubuntu-22.04
             python: '3.13'
-          - os: macos-latest
+          # ARM64 Linux builds
+          - os: ubuntu-24.04-arm
             python: '3.9'
-          - os: macos-latest
+          - os: ubuntu-24.04-arm
             python: '3.10'
-          - os: macos-latest
+          - os: ubuntu-24.04-arm
             python: '3.11'
-          - os: macos-latest
+          - os: ubuntu-24.04-arm
             python: '3.12'
-          - os: macos-latest
+          - os: ubuntu-24.04-arm
             python: '3.13'
+          - os: macos-14
+            python: '3.9'
+          - os: macos-14
+            python: '3.10'
+          - os: macos-14
+            python: '3.11'
+          - os: macos-14
+            python: '3.12'
+          - os: macos-14
+            python: '3.13'
+          - os: macos-15
+            python: '3.9'
+          - os: macos-15
+            python: '3.10'
+          - os: macos-15
+            python: '3.11'
+          - os: macos-15
+            python: '3.12'
+          - os: macos-15
+            python: '3.13'
+          - os: macos-13
+            python: '3.9'
+          - os: macos-13
+            python: '3.10'
+          - os: macos-13
+            python: '3.11'
+          - os: macos-13
+            python: '3.12'
+          # Note: macos-13 + Python 3.13 excluded due to PyTorch compatibility
+          # (PyTorch 2.5+ supports Python 3.13 but not Intel Mac x86_64)
     runs-on: ${{ matrix.os }}
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
         with:
           ref: ${{ inputs.ref }}
           submodules: recursive
@@ -78,21 +109,56 @@ jobs:
           python-version: ${{ matrix.python }}
 
       - name: Install uv
-        uses: astral-sh/setup-uv@v4
+        uses: astral-sh/setup-uv@v6
 
       - name: Install system dependencies (Ubuntu)
         if: runner.os == 'Linux'
         run: |
           sudo apt-get update
           sudo apt-get install -y libomp-dev libboost-all-dev protobuf-compiler libzmq3-dev \
-            pkg-config libopenblas-dev patchelf libabsl-dev libaio-dev libprotobuf-dev
+            pkg-config libabsl-dev libaio-dev libprotobuf-dev \
+            patchelf
 
-          # Install Intel MKL for DiskANN
-          wget -q https://registrationcenter-download.intel.com/akdlm/IRC_NAS/79153e0f-74d7-45af-b8c2-258941adf58a/intel-onemkl-2025.0.0.940.sh
-          sudo sh intel-onemkl-2025.0.0.940.sh -a --components intel.oneapi.lin.mkl.devel --action install --eula accept -s
-          source /opt/intel/oneapi/setvars.sh
-          echo "MKLROOT=/opt/intel/oneapi/mkl/latest" >> $GITHUB_ENV
-          echo "LD_LIBRARY_PATH=/opt/intel/oneapi/mkl/latest/lib/intel64:$LD_LIBRARY_PATH" >> $GITHUB_ENV
+          # Debug: Show system information
+          echo "🔍 System Information:"
+          echo "Architecture: $(uname -m)"
+          echo "OS: $(uname -a)"
+          echo "CPU info: $(lscpu | head -5)"
+
+          # Install math library based on architecture
+          ARCH=$(uname -m)
+          echo "🔍 Setting up math library for architecture: $ARCH"
+
+          if [[ "$ARCH" == "x86_64" ]]; then
+            # Install Intel MKL for DiskANN on x86_64
+            echo "📦 Installing Intel MKL for x86_64..."
+            wget -q https://registrationcenter-download.intel.com/akdlm/IRC_NAS/79153e0f-74d7-45af-b8c2-258941adf58a/intel-onemkl-2025.0.0.940.sh
+            sudo sh intel-onemkl-2025.0.0.940.sh -a --components intel.oneapi.lin.mkl.devel --action install --eula accept -s
+            source /opt/intel/oneapi/setvars.sh
+            echo "MKLROOT=/opt/intel/oneapi/mkl/latest" >> $GITHUB_ENV
+            echo "LD_LIBRARY_PATH=/opt/intel/oneapi/compiler/latest/linux/compiler/lib/intel64_lin" >> $GITHUB_ENV
+            echo "LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/opt/intel/oneapi/mkl/latest/lib/intel64" >> $GITHUB_ENV
+            echo "✅ Intel MKL installed for x86_64"
+
+            # Debug: Check MKL installation
+            echo "🔍 MKL Installation Check:"
+            ls -la /opt/intel/oneapi/mkl/latest/ || echo "MKL directory not found"
+            ls -la /opt/intel/oneapi/mkl/latest/lib/ || echo "MKL lib directory not found"
+
+          elif [[ "$ARCH" == "aarch64" ]]; then
+            # Use OpenBLAS for ARM64 (MKL installer not compatible with ARM64)
+            echo "📦 Installing OpenBLAS for ARM64..."
+            sudo apt-get install -y libopenblas-dev liblapack-dev liblapacke-dev
+            echo "✅ OpenBLAS installed for ARM64"
+
+            # Debug: Check OpenBLAS installation
+            echo "🔍 OpenBLAS Installation Check:"
+            dpkg -l | grep openblas || echo "OpenBLAS package not found"
+            ls -la /usr/lib/aarch64-linux-gnu/openblas/ || echo "OpenBLAS directory not found"
+          fi
+
+          # Debug: Show final library paths
+          echo "🔍 Final LD_LIBRARY_PATH: $LD_LIBRARY_PATH"
 
       - name: Install system dependencies (macOS)
         if: runner.os == 'macOS'
@@ -109,48 +175,73 @@ jobs:
             uv pip install --system delocate
           fi
 
+      - name: Set macOS environment variables
+        if: runner.os == 'macOS'
+        run: |
+          # Use brew --prefix to automatically detect Homebrew installation path
+          HOMEBREW_PREFIX=$(brew --prefix)
+          echo "HOMEBREW_PREFIX=${HOMEBREW_PREFIX}" >> $GITHUB_ENV
+          echo "OpenMP_ROOT=${HOMEBREW_PREFIX}/opt/libomp" >> $GITHUB_ENV
+
+          # Set CMAKE_PREFIX_PATH to let CMake find all packages automatically
+          echo "CMAKE_PREFIX_PATH=${HOMEBREW_PREFIX}" >> $GITHUB_ENV
+
+          # Set compiler flags for OpenMP (required for both backends)
+          echo "LDFLAGS=-L${HOMEBREW_PREFIX}/opt/libomp/lib" >> $GITHUB_ENV
+          echo "CPPFLAGS=-I${HOMEBREW_PREFIX}/opt/libomp/include" >> $GITHUB_ENV
+
       - name: Build packages
         run: |
           # Build core (platform independent)
-          if [[ "${{ matrix.os }}" == ubuntu-* ]]; then
-            cd packages/leann-core
-            uv build
-            cd ../..
-          fi
+          cd packages/leann-core
+          uv build
+          cd ../..
 
           # Build HNSW backend
           cd packages/leann-backend-hnsw
-          if [ "${{ matrix.os }}" == "macos-latest" ]; then
-            # Use system clang instead of homebrew LLVM for better compatibility
+          if [[ "${{ matrix.os }}" == macos-* ]]; then
+            # Use system clang for better compatibility
             export CC=clang
             export CXX=clang++
-            export MACOSX_DEPLOYMENT_TARGET=11.0
-            uv build --wheel --python python
+            # Homebrew libraries on each macOS version require matching minimum version
+            if [[ "${{ matrix.os }}" == "macos-13" ]]; then
+              export MACOSX_DEPLOYMENT_TARGET=13.0
+            elif [[ "${{ matrix.os }}" == "macos-14" ]]; then
+              export MACOSX_DEPLOYMENT_TARGET=14.0
+            elif [[ "${{ matrix.os }}" == "macos-15" ]]; then
+              export MACOSX_DEPLOYMENT_TARGET=15.0
+            fi
+            uv build --wheel --python ${{ matrix.python }} --find-links ${GITHUB_WORKSPACE}/packages/leann-core/dist
           else
-            uv build --wheel --python python
+            uv build --wheel --python ${{ matrix.python }} --find-links ${GITHUB_WORKSPACE}/packages/leann-core/dist
           fi
           cd ../..
 
           # Build DiskANN backend
           cd packages/leann-backend-diskann
-          if [ "${{ matrix.os }}" == "macos-latest" ]; then
-            # Use system clang instead of homebrew LLVM for better compatibility
+          if [[ "${{ matrix.os }}" == macos-* ]]; then
+            # Use system clang for better compatibility
             export CC=clang
             export CXX=clang++
             # DiskANN requires macOS 13.3+ for sgesdd_ LAPACK function
-            export MACOSX_DEPLOYMENT_TARGET=13.3
-            uv build --wheel --python python
+            # But Homebrew libraries on each macOS version require matching minimum version
+            if [[ "${{ matrix.os }}" == "macos-13" ]]; then
+              export MACOSX_DEPLOYMENT_TARGET=13.3
+            elif [[ "${{ matrix.os }}" == "macos-14" ]]; then
+              export MACOSX_DEPLOYMENT_TARGET=14.0
+            elif [[ "${{ matrix.os }}" == "macos-15" ]]; then
+              export MACOSX_DEPLOYMENT_TARGET=15.0
+            fi
+            uv build --wheel --python ${{ matrix.python }} --find-links ${GITHUB_WORKSPACE}/packages/leann-core/dist
           else
-            uv build --wheel --python python
+            uv build --wheel --python ${{ matrix.python }} --find-links ${GITHUB_WORKSPACE}/packages/leann-core/dist
           fi
           cd ../..
 
           # Build meta package (platform independent)
-          if [[ "${{ matrix.os }}" == ubuntu-* ]]; then
-            cd packages/leann
-            uv build
-            cd ../..
-          fi
+          cd packages/leann
+          uv build
+          cd ../..
 
       - name: Repair wheels (Linux)
         if: runner.os == 'Linux'
@@ -176,10 +267,24 @@ jobs:
       - name: Repair wheels (macOS)
         if: runner.os == 'macOS'
         run: |
+          # Determine deployment target based on runner OS
+          # Must match the Homebrew libraries for each macOS version
+          if [[ "${{ matrix.os }}" == "macos-13" ]]; then
+            HNSW_TARGET="13.0"
+            DISKANN_TARGET="13.3"
+          elif [[ "${{ matrix.os }}" == "macos-14" ]]; then
+            HNSW_TARGET="14.0"
+            DISKANN_TARGET="14.0"
+          elif [[ "${{ matrix.os }}" == "macos-15" ]]; then
+            HNSW_TARGET="15.0"
+            DISKANN_TARGET="15.0"
+          fi
+
           # Repair HNSW wheel
           cd packages/leann-backend-hnsw
           if [ -d dist ]; then
-            delocate-wheel -w dist_repaired -v dist/*.whl
+            export MACOSX_DEPLOYMENT_TARGET=$HNSW_TARGET
+            delocate-wheel -w dist_repaired -v --require-target-macos-version $HNSW_TARGET dist/*.whl
             rm -rf dist
             mv dist_repaired dist
           fi
@@ -188,7 +293,8 @@ jobs:
           # Repair DiskANN wheel
           cd packages/leann-backend-diskann
           if [ -d dist ]; then
-            delocate-wheel -w dist_repaired -v dist/*.whl
+            export MACOSX_DEPLOYMENT_TARGET=$DISKANN_TARGET
+            delocate-wheel -w dist_repaired -v --require-target-macos-version $DISKANN_TARGET dist/*.whl
             rm -rf dist
             mv dist_repaired dist
           fi
@@ -199,39 +305,34 @@ jobs:
           echo "📦 Built packages:"
           find packages/*/dist -name "*.whl" -o -name "*.tar.gz" | sort
 
+
       - name: Install built packages for testing
         run: |
-          # Create a virtual environment
-          uv venv
+          # Create a virtual environment with the correct Python version
+          uv venv --python ${{ matrix.python }}
           source .venv/bin/activate || source .venv/Scripts/activate
 
-          # Install the built wheels
-          # Use --find-links to let uv choose the correct wheel for the platform
-          if [[ "${{ matrix.os }}" == ubuntu-* ]]; then
-            uv pip install leann-core --find-links packages/leann-core/dist
-            uv pip install leann --find-links packages/leann/dist
-          fi
-          uv pip install leann-backend-hnsw --find-links packages/leann-backend-hnsw/dist
-          uv pip install leann-backend-diskann --find-links packages/leann-backend-diskann/dist
+          # Install packages using --find-links to prioritize local builds
+          uv pip install --find-links packages/leann-core/dist --find-links packages/leann-backend-hnsw/dist --find-links packages/leann-backend-diskann/dist packages/leann-core/dist/*.whl || uv pip install --find-links packages/leann-core/dist packages/leann-core/dist/*.tar.gz
+          uv pip install --find-links packages/leann-core/dist packages/leann-backend-hnsw/dist/*.whl
+          uv pip install --find-links packages/leann-core/dist packages/leann-backend-diskann/dist/*.whl
+          uv pip install packages/leann/dist/*.whl || uv pip install packages/leann/dist/*.tar.gz
 
           # Install test dependencies using extras
           uv pip install -e ".[test]"
 
       - name: Run tests with pytest
         env:
-          CI: true  # Mark as CI environment to skip memory-intensive tests
+          CI: true
           OPENAI_API_KEY: ${{ secrets.OPENAI_API_KEY }}
           HF_HUB_DISABLE_SYMLINKS: 1
           TOKENIZERS_PARALLELISM: false
-          PYTORCH_ENABLE_MPS_FALLBACK: 0  # Disable MPS on macOS CI to avoid memory issues
-          OMP_NUM_THREADS: 1  # Disable OpenMP parallelism to avoid libomp crashes
-          MKL_NUM_THREADS: 1  # Single thread for MKL operations
+          PYTORCH_ENABLE_MPS_FALLBACK: 0
+          OMP_NUM_THREADS: 1
+          MKL_NUM_THREADS: 1
         run: |
-          # Activate virtual environment
           source .venv/bin/activate || source .venv/Scripts/activate
-
-          # Run all tests
-          pytest tests/
+          pytest tests/ -v --tb=short
 
       - name: Run sanity checks (optional)
         run: |
@@ -249,3 +350,53 @@ jobs:
         with:
           name: packages-${{ matrix.os }}-py${{ matrix.python }}
           path: packages/*/dist/
+
+
+  arch-smoke:
+    name: Arch Linux smoke test (install & import)
+    needs: build
+    runs-on: ubuntu-latest
+    container:
+      image: archlinux:latest
+
+    steps:
+      - name: Prepare system
+        run: |
+          pacman -Syu --noconfirm
+          pacman -S --noconfirm python python-pip gcc git zlib openssl
+
+      - name: Download ALL wheel artifacts from this run
+        uses: actions/download-artifact@v5
+        with:
+          # Don't specify name, download all artifacts
+          path: ./wheels
+
+      - name: Install uv
+        uses: astral-sh/setup-uv@v6
+
+      - name: Create virtual environment and install wheels
+        run: |
+          uv venv
+          source .venv/bin/activate || source .venv/Scripts/activate
+          uv pip install --find-links wheels leann-core
+          uv pip install --find-links wheels leann-backend-hnsw
+          uv pip install --find-links wheels leann-backend-diskann
+          uv pip install --find-links wheels leann
+
+      - name: Import & tiny runtime check
+        env:
+          OMP_NUM_THREADS: 1
+          MKL_NUM_THREADS: 1
+        run: |
+          source .venv/bin/activate || source .venv/Scripts/activate
+          python - <<'PY'
+          import leann
+          import leann_backend_hnsw as h
+          import leann_backend_diskann as d
+          from leann import LeannBuilder, LeannSearcher
+          b = LeannBuilder(backend_name="hnsw")
+          b.add_text("hello arch")
+          b.build_index("arch_demo.leann")
+          s = LeannSearcher("arch_demo.leann")
+          print("search:", s.search("hello", top_k=1))
+          PY

.github/workflows/link-check.yml

@@ -14,6 +14,6 @@ jobs:
       - uses: actions/checkout@v4
       - uses: lycheeverse/lychee-action@v2
         with:
-          args: --no-progress --insecure README.md docs/ apps/ examples/ benchmarks/
+          args: --no-progress --insecure --user-agent 'curl/7.68.0' README.md docs/ apps/ examples/ benchmarks/
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

.gitignore

@@ -18,9 +18,11 @@ demo/experiment_results/**/*.json
 *.eml
 *.emlx
 *.json
+!.vscode/*.json
 *.sh
 *.txt
 !CMakeLists.txt
+!llms.txt
 latency_breakdown*.json
 experiment_results/eval_results/diskann/*.json
 aws/
@@ -92,3 +94,10 @@ packages/leann-backend-diskann/third_party/DiskANN/_deps/
 batchtest.py
 tests/__pytest_cache__/
 tests/__pycache__/
+paru-bin/
+
+CLAUDE.md
+CLAUDE.local.md
+.claude/*.local.*
+.claude/local/*
+benchmarks/data/

.gitmodules

@@ -14,3 +14,6 @@
 [submodule "packages/leann-backend-hnsw/third_party/libzmq"]
 	path = packages/leann-backend-hnsw/third_party/libzmq
 	url = https://github.com/zeromq/libzmq.git
+[submodule "packages/astchunk-leann"]
+	path = packages/astchunk-leann
+	url = https://github.com/yichuan-w/astchunk-leann.git

.pre-commit-config.yaml

@@ -1,6 +1,6 @@
 repos:
   - repo: https://github.com/pre-commit/pre-commit-hooks
-    rev: v4.5.0
+    rev: v5.0.0
     hooks:
       - id: trailing-whitespace
       - id: end-of-file-fixer
@@ -10,7 +10,8 @@ repos:
       - id: debug-statements
 
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: v0.2.1
+    rev: v0.12.7  # Fixed version to match pyproject.toml
     hooks:
       - id: ruff
+        args: [--fix, --exit-non-zero-on-fix]
       - id: ruff-format

.vscode/extensions.json

@@ -0,0 +1,5 @@
+{
+    "recommendations": [
+        "charliermarsh.ruff",
+    ]
+}

.vscode/settings.json

@@ -0,0 +1,22 @@
+{
+  "python.defaultInterpreterPath": ".venv/bin/python",
+  "python.terminal.activateEnvironment": true,
+  "[python]": {
+    "editor.defaultFormatter": "charliermarsh.ruff",
+    "editor.formatOnSave": true,
+    "editor.codeActionsOnSave": {
+      "source.organizeImports": "explicit",
+      "source.fixAll": "explicit"
+    },
+    "editor.insertSpaces": true,
+    "editor.tabSize": 4
+  },
+  "ruff.enable": true,
+  "files.watcherExclude": {
+    "**/.venv/**": true,
+    "**/__pycache__/**": true,
+    "**/*.egg-info/**": true,
+    "**/build/**": true,
+    "**/dist/**": true
+  }
+}

README.md

@@ -3,10 +3,13 @@
 </p>
 
 <p align="center">
-  <img src="https://img.shields.io/badge/Python-3.9%2B-blue.svg" alt="Python 3.9+">
+  <img src="https://img.shields.io/badge/Python-3.9%20%7C%203.10%20%7C%203.11%20%7C%203.12%20%7C%203.13-blue.svg" alt="Python Versions">
+  <img src="https://github.com/yichuan-w/LEANN/actions/workflows/build-and-publish.yml/badge.svg" alt="CI Status">
+  <img src="https://img.shields.io/badge/Platform-Ubuntu%20%26%20Arch%20%26%20WSL%20%7C%20macOS%20(ARM64%2FIntel)-lightgrey" alt="Platform">
   <img src="https://img.shields.io/badge/License-MIT-green.svg" alt="MIT License">
-  <img src="https://img.shields.io/badge/Platform-Linux%20%7C%20macOS-lightgrey" alt="Platform">
-  <img src="https://img.shields.io/badge/MCP-Native%20Integration-blue?style=flat-square" alt="MCP Integration">
+  <img src="https://img.shields.io/badge/MCP-Native%20Integration-blue" alt="MCP Integration">
+  <a href="https://join.slack.com/t/leann-e2u9779/shared_invite/zt-3ckd2f6w1-OX08~NN4gkWhh10PRVBj1Q"><img src="https://img.shields.io/badge/Slack-Join-4A154B?logo=slack&logoColor=white" alt="Join Slack">
+  <a href="assets/wechat_user_group.JPG" title="Join WeChat group"><img src="https://img.shields.io/badge/WeChat-Join-2DC100?logo=wechat&logoColor=white" alt="Join WeChat group"></a>
 </p>
 
 <h2 align="center" tabindex="-1" class="heading-element" dir="auto">
@@ -17,7 +20,7 @@ LEANN is an innovative vector database that democratizes personal AI. Transform
 
 LEANN achieves this through *graph-based selective recomputation* with *high-degree preserving pruning*, computing embeddings on-demand instead of storing them all. [Illustration Fig →](#️-architecture--how-it-works) | [Paper →](https://arxiv.org/abs/2506.08276)
 
-**Ready to RAG Everything?** Transform your laptop into a personal AI assistant that can semantic search your **[file system](#-personal-data-manager-process-any-documents-pdf-txt-md)**, **[emails](#-your-personal-email-secretary-rag-on-apple-mail)**, **[browser history](#-time-machine-for-the-web-rag-your-entire-browser-history)**, **[chat history](#-wechat-detective-unlock-your-golden-memories)**, **[codebase](#-claude-code-integration-transform-your-development-workflow)**\* , or external knowledge bases (i.e., 60M documents) - all on your laptop, with zero cloud costs and complete privacy.
+**Ready to RAG Everything?** Transform your laptop into a personal AI assistant that can semantic search your **[file system](#-personal-data-manager-process-any-documents-pdf-txt-md)**, **[emails](#-your-personal-email-secretary-rag-on-apple-mail)**, **[browser history](#-time-machine-for-the-web-rag-your-entire-browser-history)**, **[chat history](#-wechat-detective-unlock-your-golden-memories)** ([WeChat](#-wechat-detective-unlock-your-golden-memories), [iMessage](#-imessage-history-your-personal-conversation-archive)), **[agent memory](#-chatgpt-chat-history-your-personal-ai-conversation-archive)** ([ChatGPT](#-chatgpt-chat-history-your-personal-ai-conversation-archive), [Claude](#-claude-chat-history-your-personal-ai-conversation-archive)), **[codebase](#-claude-code-integration-transform-your-development-workflow)**\* , or external knowledge bases (i.e., 60M documents) - all on your laptop, with zero cloud costs and complete privacy.
 
 
 \* Claude Code only supports basic `grep`-style keyword search. **LEANN** is a drop-in **semantic search MCP service fully compatible with Claude Code**, unlocking intelligent retrieval without changing your workflow. 🔥 Check out [the easy setup →](packages/leann-mcp/README.md)
@@ -30,7 +33,7 @@ LEANN achieves this through *graph-based selective recomputation* with *high-deg
   <img src="assets/effects.png" alt="LEANN vs Traditional Vector DB Storage Comparison" width="70%">
 </p>
 
-> **The numbers speak for themselves:** Index 60 million text chunks in just 6GB instead of 201GB. From emails to browser history, everything fits on your laptop. [See detailed benchmarks for different applications below ↓](#storage-comparison)
+> **The numbers speak for themselves:** Index 60 million text chunks in just 6GB instead of 201GB. From emails to browser history, everything fits on your laptop. [See detailed benchmarks for different applications below ↓](#-storage-comparison)
 
 
 🔒 **Privacy:** Your data never leaves your laptop. No OpenAI, no cloud, no "terms of service".
@@ -69,6 +72,8 @@ uv venv
 source .venv/bin/activate
 uv pip install leann
 ```
+<!--
+> Low-resource? See “Low-resource setups” in the [Configuration Guide](docs/configuration-guide.md#low-resource-setups). -->
 
 <details>
 <summary>
@@ -84,15 +89,60 @@ git submodule update --init --recursive
 ```
 
 **macOS:**
+
+Note: DiskANN requires MacOS 13.3 or later.
+
 ```bash
-brew install llvm libomp boost protobuf zeromq pkgconf
-CC=$(brew --prefix llvm)/bin/clang CXX=$(brew --prefix llvm)/bin/clang++ uv sync
+brew install libomp boost protobuf zeromq pkgconf
+uv sync --extra diskann
 ```
 
-**Linux:**
+**Linux (Ubuntu/Debian):**
+
+Note: On Ubuntu 20.04, you may need to build a newer Abseil and pin Protobuf (e.g., v3.20.x) for building DiskANN. See [Issue #30](https://github.com/yichuan-w/LEANN/issues/30) for a step-by-step note.
+
+You can manually install [Intel oneAPI MKL](https://www.intel.com/content/www/us/en/developer/tools/oneapi/onemkl.html) instead of `libmkl-full-dev` for DiskANN. You can also use `libopenblas-dev` for building HNSW only, by removing `--extra diskann` in the command below.
+
 ```bash
-sudo apt-get install libomp-dev libboost-all-dev protobuf-compiler libabsl-dev libmkl-full-dev libaio-dev libzmq3-dev
-uv sync
+sudo apt-get update && sudo apt-get install -y \
+  libomp-dev libboost-all-dev protobuf-compiler libzmq3-dev \
+  pkg-config libabsl-dev libaio-dev libprotobuf-dev \
+  libmkl-full-dev
+
+uv sync --extra diskann
+```
+
+**Linux (Arch Linux):**
+
+```bash
+sudo pacman -Syu && sudo pacman -S --needed base-devel cmake pkgconf git gcc \
+  boost boost-libs protobuf abseil-cpp libaio zeromq
+
+# For MKL in DiskANN
+sudo pacman -S --needed base-devel git
+git clone https://aur.archlinux.org/paru-bin.git
+cd paru-bin && makepkg -si
+paru -S intel-oneapi-mkl intel-oneapi-compiler
+source /opt/intel/oneapi/setvars.sh
+
+uv sync --extra diskann
+```
+
+**Linux (RHEL / CentOS Stream / Oracle / Rocky / AlmaLinux):**
+
+See [Issue #50](https://github.com/yichuan-w/LEANN/issues/50) for more details.
+
+```bash
+sudo dnf groupinstall -y "Development Tools"
+sudo dnf install -y libomp-devel boost-devel protobuf-compiler protobuf-devel \
+  abseil-cpp-devel libaio-devel zeromq-devel pkgconf-pkg-config
+
+# For MKL in DiskANN
+sudo dnf install -y intel-oneapi-mkl intel-oneapi-mkl-devel \
+  intel-oneapi-openmp || sudo dnf install -y intel-oneapi-compiler
+source /opt/intel/oneapi/setvars.sh
+
+uv sync --extra diskann
 ```
 
 </details>
@@ -126,7 +176,9 @@ response = chat.ask("How much storage does LEANN save?", top_k=1)
 
 ## RAG on Everything!
 
-LEANN supports RAG on various data sources including documents (`.pdf`, `.txt`, `.md`), Apple Mail, Google Search History, WeChat, and more.
+LEANN supports RAG on various data sources including documents (`.pdf`, `.txt`, `.md`), Apple Mail, Google Search History, WeChat, ChatGPT conversations, Claude conversations, iMessage conversations, and **live data from any platform through MCP (Model Context Protocol) servers** - including Slack, Twitter, and more.
+
+
 
 ### Generation Model Setup
 
@@ -170,7 +222,8 @@ ollama pull llama3.2:1b
 
 </details>
 
-### ⭐ Flexible Configuration
+
+## ⭐ Flexible Configuration
 
 LEANN provides flexible parameters for embedding models, search strategies, and data processing to fit your specific needs.
 
@@ -183,34 +236,34 @@ All RAG examples share these common parameters. **Interactive mode** is availabl
 
 ```bash
 # Core Parameters (General preprocessing for all examples)
---index-dir DIR          # Directory to store the index (default: current directory)
---query "YOUR QUESTION"  # Single query mode. Omit for interactive chat (type 'quit' to exit), and now you can play with your index interactively
---max-items N           # Limit data preprocessing (default: -1, process all data)
---force-rebuild         # Force rebuild index even if it exists
+--index-dir DIR              # Directory to store the index (default: current directory)
+--query "YOUR QUESTION"      # Single query mode. Omit for interactive chat (type 'quit' to exit), and now you can play with your index interactively
+--max-items N                # Limit data preprocessing (default: -1, process all data)
+--force-rebuild              # Force rebuild index even if it exists
 
 # Embedding Parameters
---embedding-model MODEL  # e.g., facebook/contriever, text-embedding-3-small, nomic-embed-text, or mlx-community/multilingual-e5-base-mlx
---embedding-mode MODE    # sentence-transformers, openai, mlx, or ollama
+--embedding-model MODEL      # e.g., facebook/contriever, text-embedding-3-small, mlx-community/Qwen3-Embedding-0.6B-8bit or nomic-embed-text
+--embedding-mode MODE        # sentence-transformers, openai, mlx, or ollama
 
 # LLM Parameters (Text generation models)
---llm TYPE              # LLM backend: openai, ollama, or hf (default: openai)
---llm-model MODEL       # Model name (default: gpt-4o) e.g., gpt-4o-mini, llama3.2:1b, Qwen/Qwen2.5-1.5B-Instruct
---thinking-budget LEVEL # Thinking budget for reasoning models: low/medium/high (supported by o3, o3-mini, GPT-Oss:20b, and other reasoning models)
+--llm TYPE                   # LLM backend: openai, ollama, or hf (default: openai)
+--llm-model MODEL            # Model name (default: gpt-4o) e.g., gpt-4o-mini, llama3.2:1b, Qwen/Qwen2.5-1.5B-Instruct
+--thinking-budget LEVEL      # Thinking budget for reasoning models: low/medium/high (supported by o3, o3-mini, GPT-Oss:20b, and other reasoning models)
 
 # Search Parameters
---top-k N               # Number of results to retrieve (default: 20)
---search-complexity N   # Search complexity for graph traversal (default: 32)
+--top-k N                    # Number of results to retrieve (default: 20)
+--search-complexity N        # Search complexity for graph traversal (default: 32)
 
 # Chunking Parameters
---chunk-size N          # Size of text chunks (default varies by source: 256 for most, 192 for WeChat)
---chunk-overlap N       # Overlap between chunks (default varies: 25-128 depending on source)
+--chunk-size N               # Size of text chunks (default varies by source: 256 for most, 192 for WeChat)
+--chunk-overlap N            # Overlap between chunks (default varies: 25-128 depending on source)
 
 # Index Building Parameters
---backend-name NAME     # Backend to use: hnsw or diskann (default: hnsw)
---graph-degree N        # Graph degree for index construction (default: 32)
---build-complexity N    # Build complexity for index construction (default: 64)
---no-compact           # Disable compact index storage (compact storage IS enabled to save storage by default)
---no-recompute         # Disable embedding recomputation (recomputation IS enabled to save storage by default)
+--backend-name NAME          # Backend to use: hnsw or diskann (default: hnsw)
+--graph-degree N             # Graph degree for index construction (default: 32)
+--build-complexity N         # Build complexity for index construction (default: 64)
+--compact / --no-compact     # Use compact storage (default: true). Must be `no-compact` for `no-recompute` build.
+--recompute / --no-recompute # Enable/disable embedding recomputation (default: enabled). Should not do a `no-recompute` search in a `recompute` build.
 ```
 
 </details>
@@ -246,6 +299,12 @@ python -m apps.document_rag --data-dir "~/Documents/Papers" --chunk-size 1024
 
 # Filter only markdown and Python files with smaller chunks
 python -m apps.document_rag --data-dir "./docs" --chunk-size 256 --file-types .md .py
+
+# Enable AST-aware chunking for code files
+python -m apps.document_rag --enable-code-chunking --data-dir "./my_project"
+
+# Or use the specialized code RAG for better code understanding
+python -m apps.code_rag --repo-dir "./my_codebase" --query "How does authentication work?"
 ```
 
 </details>
@@ -418,26 +477,385 @@ Once the index is built, you can ask questions like:
 
 </details>
 
+### 🤖 ChatGPT Chat History: Your Personal AI Conversation Archive!
+
+Transform your ChatGPT conversations into a searchable knowledge base! Search through all your ChatGPT discussions about coding, research, brainstorming, and more.
+
+```bash
+python -m apps.chatgpt_rag --export-path chatgpt_export.html --query "How do I create a list in Python?"
+```
+
+**Unlock your AI conversation history.** Never lose track of valuable insights from your ChatGPT discussions again.
+
+<details>
+<summary><strong>📋 Click to expand: How to Export ChatGPT Data</strong></summary>
+
+**Step-by-step export process:**
+
+1. **Sign in to ChatGPT**
+2. **Click your profile icon** in the top right corner
+3. **Navigate to Settings** → **Data Controls**
+4. **Click "Export"** under Export Data
+5. **Confirm the export** request
+6. **Download the ZIP file** from the email link (expires in 24 hours)
+7. **Extract or use directly** with LEANN
+
+**Supported formats:**
+- `.html` files from ChatGPT exports
+- `.zip` archives from ChatGPT
+- Directories with multiple export files
+
+</details>
+
+<details>
+<summary><strong>📋 Click to expand: ChatGPT-Specific Arguments</strong></summary>
+
+#### Parameters
+```bash
+--export-path PATH           # Path to ChatGPT export file (.html/.zip) or directory (default: ./chatgpt_export)
+--separate-messages         # Process each message separately instead of concatenated conversations
+--chunk-size N              # Text chunk size (default: 512)
+--chunk-overlap N           # Overlap between chunks (default: 128)
+```
+
+#### Example Commands
+```bash
+# Basic usage with HTML export
+python -m apps.chatgpt_rag --export-path conversations.html
+
+# Process ZIP archive from ChatGPT
+python -m apps.chatgpt_rag --export-path chatgpt_export.zip
+
+# Search with specific query
+python -m apps.chatgpt_rag --export-path chatgpt_data.html --query "Python programming help"
+
+# Process individual messages for fine-grained search
+python -m apps.chatgpt_rag --separate-messages --export-path chatgpt_export.html
+
+# Process directory containing multiple exports
+python -m apps.chatgpt_rag --export-path ./chatgpt_exports/ --max-items 1000
+```
+
+</details>
+
+<details>
+<summary><strong>💡 Click to expand: Example queries you can try</strong></summary>
+
+Once your ChatGPT conversations are indexed, you can search with queries like:
+- "What did I ask ChatGPT about Python programming?"
+- "Show me conversations about machine learning algorithms"
+- "Find discussions about web development frameworks"
+- "What coding advice did ChatGPT give me?"
+- "Search for conversations about debugging techniques"
+- "Find ChatGPT's recommendations for learning resources"
+
+</details>
+
+### 🤖 Claude Chat History: Your Personal AI Conversation Archive!
+
+Transform your Claude conversations into a searchable knowledge base! Search through all your Claude discussions about coding, research, brainstorming, and more.
+
+```bash
+python -m apps.claude_rag --export-path claude_export.json --query "What did I ask about Python dictionaries?"
+```
+
+**Unlock your AI conversation history.** Never lose track of valuable insights from your Claude discussions again.
+
+<details>
+<summary><strong>📋 Click to expand: How to Export Claude Data</strong></summary>
+
+**Step-by-step export process:**
+
+1. **Open Claude** in your browser
+2. **Navigate to Settings** (look for gear icon or settings menu)
+3. **Find Export/Download** options in your account settings
+4. **Download conversation data** (usually in JSON format)
+5. **Place the file** in your project directory
+
+*Note: Claude export methods may vary depending on the interface you're using. Check Claude's help documentation for the most current export instructions.*
+
+**Supported formats:**
+- `.json` files (recommended)
+- `.zip` archives containing JSON data
+- Directories with multiple export files
+
+</details>
+
+<details>
+<summary><strong>📋 Click to expand: Claude-Specific Arguments</strong></summary>
+
+#### Parameters
+```bash
+--export-path PATH           # Path to Claude export file (.json/.zip) or directory (default: ./claude_export)
+--separate-messages         # Process each message separately instead of concatenated conversations
+--chunk-size N              # Text chunk size (default: 512)
+--chunk-overlap N           # Overlap between chunks (default: 128)
+```
+
+#### Example Commands
+```bash
+# Basic usage with JSON export
+python -m apps.claude_rag --export-path my_claude_conversations.json
+
+# Process ZIP archive from Claude
+python -m apps.claude_rag --export-path claude_export.zip
+
+# Search with specific query
+python -m apps.claude_rag --export-path claude_data.json --query "machine learning advice"
+
+# Process individual messages for fine-grained search
+python -m apps.claude_rag --separate-messages --export-path claude_export.json
+
+# Process directory containing multiple exports
+python -m apps.claude_rag --export-path ./claude_exports/ --max-items 1000
+```
+
+</details>
+
+<details>
+<summary><strong>💡 Click to expand: Example queries you can try</strong></summary>
+
+Once your Claude conversations are indexed, you can search with queries like:
+- "What did I ask Claude about Python programming?"
+- "Show me conversations about machine learning algorithms"
+- "Find discussions about software architecture patterns"
+- "What debugging advice did Claude give me?"
+- "Search for conversations about data structures"
+- "Find Claude's recommendations for learning resources"
+
+</details>
+
+### 💬 iMessage History: Your Personal Conversation Archive!
+
+Transform your iMessage conversations into a searchable knowledge base! Search through all your text messages, group chats, and conversations with friends, family, and colleagues.
+
+```bash
+python -m apps.imessage_rag --query "What did we discuss about the weekend plans?"
+```
+
+**Unlock your message history.** Never lose track of important conversations, shared links, or memorable moments from your iMessage history.
+
+<details>
+<summary><strong>📋 Click to expand: How to Access iMessage Data</strong></summary>
+
+**iMessage data location:**
+
+iMessage conversations are stored in a SQLite database on your Mac at:
+```
+~/Library/Messages/chat.db
+```
+
+**Important setup requirements:**
+
+1. **Grant Full Disk Access** to your terminal or IDE:
+   - Open **System Preferences** → **Security & Privacy** → **Privacy**
+   - Select **Full Disk Access** from the left sidebar
+   - Click the **+** button and add your terminal app (Terminal, iTerm2) or IDE (VS Code, etc.)
+   - Restart your terminal/IDE after granting access
+
+2. **Alternative: Use a backup database**
+   - If you have Time Machine backups or manual copies of the database
+   - Use `--db-path` to specify a custom location
+
+**Supported formats:**
+- Direct access to `~/Library/Messages/chat.db` (default)
+- Custom database path with `--db-path`
+- Works with backup copies of the database
+
+</details>
+
+<details>
+<summary><strong>📋 Click to expand: iMessage-Specific Arguments</strong></summary>
+
+#### Parameters
+```bash
+--db-path PATH                    # Path to chat.db file (default: ~/Library/Messages/chat.db)
+--concatenate-conversations       # Group messages by conversation (default: True)
+--no-concatenate-conversations    # Process each message individually
+--chunk-size N                    # Text chunk size (default: 1000)
+--chunk-overlap N                 # Overlap between chunks (default: 200)
+```
+
+#### Example Commands
+```bash
+# Basic usage (requires Full Disk Access)
+python -m apps.imessage_rag
+
+# Search with specific query
+python -m apps.imessage_rag --query "family dinner plans"
+
+# Use custom database path
+python -m apps.imessage_rag --db-path /path/to/backup/chat.db
+
+# Process individual messages instead of conversations
+python -m apps.imessage_rag --no-concatenate-conversations
+
+# Limit processing for testing
+python -m apps.imessage_rag --max-items 100 --query "weekend"
+```
+
+</details>
+
+<details>
+<summary><strong>💡 Click to expand: Example queries you can try</strong></summary>
+
+Once your iMessage conversations are indexed, you can search with queries like:
+- "What did we discuss about vacation plans?"
+- "Find messages about restaurant recommendations"
+- "Show me conversations with John about the project"
+- "Search for shared links about technology"
+- "Find group chat discussions about weekend events"
+- "What did mom say about the family gathering?"
+
+</details>
+
+### 🔌 MCP Integration: RAG on Live Data from Any Platform!
+
+**NEW!** Connect to live data sources through the Model Context Protocol (MCP). LEANN now supports real-time RAG on platforms like Slack, Twitter, and more through standardized MCP servers.
+
+**Key Benefits:**
+- 🔄 **Live Data Access**: Fetch real-time data without manual exports
+- 🔌 **Standardized Protocol**: Use any MCP-compatible server
+- 🚀 **Easy Extension**: Add new platforms with minimal code
+- 🔒 **Secure Access**: MCP servers handle authentication
+
+<details>
+<summary><strong>💬 Slack Messages: Search Your Team Conversations</strong></summary>
+
+Transform your Slack workspace into a searchable knowledge base! Find discussions, decisions, and shared knowledge across all your channels.
+
+```bash
+# Test MCP server connection
+python -m apps.slack_rag --mcp-server "slack-mcp-server" --test-connection
+
+# Index and search Slack messages
+python -m apps.slack_rag \
+  --mcp-server "slack-mcp-server" \
+  --workspace-name "my-team" \
+  --channels general dev-team random \
+  --query "What did we decide about the product launch?"
+```
+
+**Setup Requirements:**
+1. Install a Slack MCP server (e.g., `npm install -g slack-mcp-server`)
+2. Configure Slack API credentials:
+   ```bash
+   export SLACK_BOT_TOKEN="xoxb-your-bot-token"
+   export SLACK_APP_TOKEN="xapp-your-app-token"
+   ```
+3. Test connection with `--test-connection` flag
+
+**Arguments:**
+- `--mcp-server`: Command to start the Slack MCP server
+- `--workspace-name`: Slack workspace name for organization
+- `--channels`: Specific channels to index (optional)
+- `--concatenate-conversations`: Group messages by channel (default: true)
+- `--max-messages-per-channel`: Limit messages per channel (default: 100)
+
+</details>
+
+<details>
+<summary><strong>🐦 Twitter Bookmarks: Your Personal Tweet Library</strong></summary>
+
+Search through your Twitter bookmarks! Find that perfect article, thread, or insight you saved for later.
+
+```bash
+# Test MCP server connection
+python -m apps.twitter_rag --mcp-server "twitter-mcp-server" --test-connection
+
+# Index and search Twitter bookmarks
+python -m apps.twitter_rag \
+  --mcp-server "twitter-mcp-server" \
+  --max-bookmarks 1000 \
+  --query "What AI articles did I bookmark about machine learning?"
+```
+
+**Setup Requirements:**
+1. Install a Twitter MCP server (e.g., `npm install -g twitter-mcp-server`)
+2. Configure Twitter API credentials:
+   ```bash
+   export TWITTER_API_KEY="your-api-key"
+   export TWITTER_API_SECRET="your-api-secret"
+   export TWITTER_ACCESS_TOKEN="your-access-token"
+   export TWITTER_ACCESS_TOKEN_SECRET="your-access-token-secret"
+   ```
+3. Test connection with `--test-connection` flag
+
+**Arguments:**
+- `--mcp-server`: Command to start the Twitter MCP server
+- `--username`: Filter bookmarks by username (optional)
+- `--max-bookmarks`: Maximum bookmarks to fetch (default: 1000)
+- `--no-tweet-content`: Exclude tweet content, only metadata
+- `--no-metadata`: Exclude engagement metadata
+
+</details>
+
+<details>
+<summary><strong>💡 Click to expand: Example queries you can try</strong></summary>
+
+**Slack Queries:**
+- "What did the team discuss about the project deadline?"
+- "Find messages about the new feature launch"
+- "Show me conversations about budget planning"
+- "What decisions were made in the dev-team channel?"
+
+**Twitter Queries:**
+- "What AI articles did I bookmark last month?"
+- "Find tweets about machine learning techniques"
+- "Show me bookmarked threads about startup advice"
+- "What Python tutorials did I save?"
+
+</details>
+
+<details>
+<summary><strong>🔧 Adding New MCP Platforms</strong></summary>
+
+Want to add support for other platforms? LEANN's MCP integration is designed for easy extension:
+
+1. **Find or create an MCP server** for your platform
+2. **Create a reader class** following the pattern in `apps/slack_data/slack_mcp_reader.py`
+3. **Create a RAG application** following the pattern in `apps/slack_rag.py`
+4. **Test and contribute** back to the community!
+
+**Popular MCP servers to explore:**
+- GitHub repositories and issues
+- Discord messages
+- Notion pages
+- Google Drive documents
+- And many more in the MCP ecosystem!
+
+</details>
+
 ### 🚀 Claude Code Integration: Transform Your Development Workflow!
 
+<details>
+<summary><strong>NEW!! AST‑Aware Code Chunking</strong></summary>
+
+LEANN features intelligent code chunking that preserves semantic boundaries (functions, classes, methods) for Python, Java, C#, and TypeScript, improving code understanding compared to text-based chunking.
+
+📖 Read the [AST Chunking Guide →](docs/ast_chunking_guide.md)
+
+</details>
+
 **The future of code assistance is here.** Transform your development workflow with LEANN's native MCP integration for Claude Code. Index your entire codebase and get intelligent code assistance directly in your IDE.
 
 **Key features:**
-- 🔍 **Semantic code search** across your entire project
+- 🔍 **Semantic code search** across your entire project, fully local index and lightweight
+- 🧠 **AST-aware chunking** preserves code structure (functions, classes)
 - 📚 **Context-aware assistance** for debugging and development
 - 🚀 **Zero-config setup** with automatic language detection
 
 ```bash
 # Install LEANN globally for MCP integration
-uv tool install leann-core
-
+uv tool install leann-core --with leann
+claude mcp add --scope user leann-server -- leann_mcp
 # Setup is automatic - just start using Claude Code!
 ```
 Try our fully agentic pipeline with auto query rewriting, semantic search planning, and more:
 
 ![LEANN MCP Integration](assets/mcp_leann.png)
 
-**Ready to supercharge your coding?** [Complete Setup Guide →](packages/leann-mcp/README.md)
+**🔥 Ready to supercharge your coding?** [Complete Setup Guide →](packages/leann-mcp/README.md)
 
 ## 🖥️ Command Line Interface
 
@@ -454,7 +872,8 @@ leann --help
 **To make it globally available:**
 ```bash
 # Install the LEANN CLI globally using uv tool
-uv tool install leann
+uv tool install leann-core --with leann
+
 
 # Now you can use leann from anywhere without activating venv
 leann --help
@@ -467,7 +886,7 @@ leann --help
 ### Usage Examples
 
 ```bash
-# build from a specific directory, and my_docs is the index name
+# build from a specific directory, and my_docs is the index name(Here you can also build from multiple dict or multiple files)
 leann build my-docs --docs ./your_documents
 
 # Search your documents
@@ -478,30 +897,36 @@ leann ask my-docs --interactive
 
 # List all your indexes
 leann list
+
+# Remove an index
+leann remove my-docs
 ```
 
 **Key CLI features:**
-- Auto-detects document formats (PDF, TXT, MD, DOCX)
-- Smart text chunking with overlap
+- Auto-detects document formats (PDF, TXT, MD, DOCX, PPTX + code files)
+- **🧠 AST-aware chunking** for Python, Java, C#, TypeScript files
+- Smart text chunking with overlap for all other content
 - Multiple LLM providers (Ollama, OpenAI, HuggingFace)
-- Organized index storage in `~/.leann/indexes/`
+- Organized index storage in `.leann/indexes/` (project-local)
 - Support for advanced search parameters
 
 <details>
 <summary><strong>📋 Click to expand: Complete CLI Reference</strong></summary>
 
+You can use `leann --help`, or `leann build --help`, `leann search --help`, `leann ask --help`, `leann list --help`, `leann remove --help` to get the complete CLI reference.
+
 **Build Command:**
 ```bash
-leann build INDEX_NAME --docs DIRECTORY [OPTIONS]
+leann build INDEX_NAME --docs DIRECTORY|FILE [DIRECTORY|FILE ...] [OPTIONS]
 
 Options:
   --backend {hnsw,diskann}     Backend to use (default: hnsw)
   --embedding-model MODEL      Embedding model (default: facebook/contriever)
-  --graph-degree N            Graph degree (default: 32)
-  --complexity N              Build complexity (default: 64)
-  --force                     Force rebuild existing index
-  --compact                   Use compact storage (default: true)
-  --recompute                 Enable recomputation (default: true)
+  --graph-degree N             Graph degree (default: 32)
+  --complexity N               Build complexity (default: 64)
+  --force                      Force rebuild existing index
+  --compact / --no-compact     Use compact storage (default: true). Must be `no-compact` for `no-recompute` build.
+  --recompute / --no-recompute Enable recomputation (default: true)
 ```
 
 **Search Command:**
@@ -509,9 +934,9 @@ Options:
 leann search INDEX_NAME QUERY [OPTIONS]
 
 Options:
-  --top-k N                   Number of results (default: 5)
-  --complexity N              Search complexity (default: 64)
-  --recompute-embeddings      Use recomputation for highest accuracy
+  --top-k N                     Number of results (default: 5)
+  --complexity N                Search complexity (default: 64)
+  --recompute / --no-recompute  Enable/disable embedding recomputation (default: enabled). Should not do a `no-recompute` search in a `recompute` build.
   --pruning-strategy {global,local,proportional}
 ```
 
@@ -526,8 +951,73 @@ Options:
   --top-k N                  Retrieval count (default: 20)
 ```
 
+**List Command:**
+```bash
+leann list
+
+# Lists all indexes across all projects with status indicators:
+# ✅ - Index is complete and ready to use
+# ❌ - Index is incomplete or corrupted
+# 📁 - CLI-created index (in .leann/indexes/)
+# 📄 - App-created index (*.leann.meta.json files)
+```
+
+**Remove Command:**
+```bash
+leann remove INDEX_NAME [OPTIONS]
+
+Options:
+  --force, -f    Force removal without confirmation
+
+# Smart removal: automatically finds and safely removes indexes
+# - Shows all matching indexes across projects
+# - Requires confirmation for cross-project removal
+# - Interactive selection when multiple matches found
+# - Supports both CLI and app-created indexes
+```
+
 </details>
 
+## 🚀 Advanced Features
+
+### 🎯 Metadata Filtering
+
+LEANN supports a simple metadata filtering system to enable sophisticated use cases like document filtering by date/type, code search by file extension, and content management based on custom criteria.
+
+```python
+# Add metadata during indexing
+builder.add_text(
+    "def authenticate_user(token): ...",
+    metadata={"file_extension": ".py", "lines_of_code": 25}
+)
+
+# Search with filters
+results = searcher.search(
+    query="authentication function",
+    metadata_filters={
+        "file_extension": {"==": ".py"},
+        "lines_of_code": {"<": 100}
+    }
+)
+```
+
+**Supported operators**: `==`, `!=`, `<`, `<=`, `>`, `>=`, `in`, `not_in`, `contains`, `starts_with`, `ends_with`, `is_true`, `is_false`
+
+📖 **[Complete Metadata filtering guide →](docs/metadata_filtering.md)**
+
+### 🔍 Grep Search
+
+For exact text matching instead of semantic search, use the `use_grep` parameter:
+
+```python
+# Exact text search
+results = searcher.search("banana‑crocodile", use_grep=True, top_k=1)
+```
+
+**Use cases**: Finding specific code patterns, error messages, function names, or exact phrases where semantic similarity isn't needed.
+
+📖 **[Complete grep search guide →](docs/grep_search.md)**
+
 ## 🏗️ Architecture & How It Works
 
 <p align="center">
@@ -542,12 +1032,16 @@ Options:
 - **Dynamic batching:** Efficiently batch embedding computations for GPU utilization
 - **Two-level search:** Smart graph traversal that prioritizes promising nodes
 
-**Backends:** HNSW (default) for most use cases, with optional DiskANN support for billion-scale datasets.
+**Backends:**
+- **HNSW** (default): Ideal for most datasets with maximum storage savings through full recomputation
+- **DiskANN**: Advanced option with superior search performance, using PQ-based graph traversal with real-time reranking for the best speed-accuracy trade-off
 
 ## Benchmarks
 
+**[DiskANN vs HNSW Performance Comparison →](benchmarks/diskann_vs_hnsw_speed_comparison.py)** - Compare search performance between both backends
+
+**[Simple Example: Compare LEANN vs FAISS →](benchmarks/compare_faiss_vs_leann.py)** - See storage savings in action
 
-**[Simple Example: Compare LEANN vs FAISS →](benchmarks/compare_faiss_vs_leann.py)**
 ### 📊 Storage Comparison
 
 | System | DPR (2.1M) | Wiki (60M) | Chat (400K) | Email (780K) | Browser (38K) |
@@ -563,6 +1057,7 @@ Options:
 ```bash
 uv pip install -e ".[dev]"  # Install dev dependencies
 python benchmarks/run_evaluation.py    # Will auto-download evaluation data and run benchmarks
+python benchmarks/run_evaluation.py benchmarks/data/indices/rpj_wiki/rpj_wiki --num-queries 2000    # After downloading data, you can run the benchmark with our biggest index
 ```
 
 The evaluation script downloads data automatically on first run. The last three results were tested with partial personal data, and you can reproduce them with your own data!
@@ -602,12 +1097,16 @@ MIT License - see [LICENSE](LICENSE) for details.
 
 Core Contributors: [Yichuan Wang](https://yichuan-w.github.io/) & [Zhifei Li](https://github.com/andylizf).
 
+Active Contributors: [Gabriel Dehan](https://github.com/gabriel-dehan), [Aakash Suresh](https://github.com/ASuresh0524)
+
+
 We welcome more contributors! Feel free to open issues or submit PRs.
 
 This work is done at [**Berkeley Sky Computing Lab**](https://sky.cs.berkeley.edu/).
 
----
+## Star History
 
+[![Star History Chart](https://api.star-history.com/svg?repos=yichuan-w/LEANN&type=Date)](https://www.star-history.com/#yichuan-w/LEANN&Date)
 <p align="center">
   <strong>⭐ Star us on GitHub if Leann is useful for your research or applications!</strong>
 </p>

apps/base_rag_example.py

@@ -10,7 +10,7 @@ from typing import Any
 
 import dotenv
 from leann.api import LeannBuilder, LeannChat
-from llama_index.core.node_parser import SentenceSplitter
+from leann.registry import register_project_directory
 
 dotenv.load_dotenv()
 
@@ -69,14 +69,14 @@ class BaseRAGExample(ABC):
             "--embedding-model",
             type=str,
             default=embedding_model_default,
-            help=f"Embedding model to use (default: {embedding_model_default})",
+            help=f"Embedding model to use (default: {embedding_model_default}), we provide facebook/contriever, text-embedding-3-small,mlx-community/Qwen3-Embedding-0.6B-8bit or nomic-embed-text",
         )
         embedding_group.add_argument(
             "--embedding-mode",
             type=str,
             default="sentence-transformers",
             choices=["sentence-transformers", "openai", "mlx", "ollama"],
-            help="Embedding backend mode (default: sentence-transformers)",
+            help="Embedding backend mode (default: sentence-transformers), we provide sentence-transformers, openai, mlx, or ollama",
         )
 
         # LLM parameters
@@ -86,13 +86,13 @@ class BaseRAGExample(ABC):
             type=str,
             default="openai",
             choices=["openai", "ollama", "hf", "simulated"],
-            help="LLM backend to use (default: openai)",
+            help="LLM backend: openai, ollama, or hf (default: openai)",
         )
         llm_group.add_argument(
             "--llm-model",
             type=str,
             default=None,
-            help="LLM model name (default: gpt-4o for openai, llama3.2:1b for ollama)",
+            help="Model name (default: gpt-4o) e.g., gpt-4o-mini, llama3.2:1b, Qwen/Qwen2.5-1.5B-Instruct",
         )
         llm_group.add_argument(
             "--llm-host",
@@ -108,6 +108,38 @@ class BaseRAGExample(ABC):
             help="Thinking budget for reasoning models (low/medium/high). Supported by GPT-Oss:20b and other reasoning models.",
         )
 
+        # AST Chunking parameters
+        ast_group = parser.add_argument_group("AST Chunking Parameters")
+        ast_group.add_argument(
+            "--use-ast-chunking",
+            action="store_true",
+            help="Enable AST-aware chunking for code files (requires astchunk)",
+        )
+        ast_group.add_argument(
+            "--ast-chunk-size",
+            type=int,
+            default=512,
+            help="Maximum characters per AST chunk (default: 512)",
+        )
+        ast_group.add_argument(
+            "--ast-chunk-overlap",
+            type=int,
+            default=64,
+            help="Overlap between AST chunks (default: 64)",
+        )
+        ast_group.add_argument(
+            "--code-file-extensions",
+            nargs="+",
+            default=None,
+            help="Additional code file extensions to process with AST chunking (e.g., .py .java .cs .ts)",
+        )
+        ast_group.add_argument(
+            "--ast-fallback-traditional",
+            action="store_true",
+            default=True,
+            help="Fall back to traditional chunking if AST chunking fails (default: True)",
+        )
+
         # Search parameters
         search_group = parser.add_argument_group("Search Parameters")
         search_group.add_argument(
@@ -178,6 +210,9 @@ class BaseRAGExample(ABC):
             config["host"] = args.llm_host
         elif args.llm == "hf":
             config["model"] = args.llm_model or "Qwen/Qwen2.5-1.5B-Instruct"
+        elif args.llm == "simulated":
+            # Simulated LLM doesn't need additional configuration
+            pass
 
         return config
 
@@ -211,6 +246,11 @@ class BaseRAGExample(ABC):
         builder.build_index(index_path)
         print(f"Index saved to: {index_path}")
 
+        # Register project directory so leann list can discover this index
+        # The index is saved as args.index_dir/index_name.leann
+        # We want to register the current working directory where the app is run
+        register_project_directory(Path.cwd())
+
         return index_path
 
     async def run_interactive_chat(self, args, index_path: str):
@@ -259,7 +299,6 @@ class BaseRAGExample(ABC):
         chat = LeannChat(
             index_path,
             llm_config=self.get_llm_config(args),
-            system_prompt=f"You are a helpful assistant that answers questions about {self.name} data.",
             complexity=args.search_complexity,
         )
 
@@ -301,21 +340,3 @@ class BaseRAGExample(ABC):
             await self.run_single_query(args, index_path, args.query)
         else:
             await self.run_interactive_chat(args, index_path)
-
-
-def create_text_chunks(documents, chunk_size=256, chunk_overlap=25) -> list[str]:
-    """Helper function to create text chunks from documents."""
-    node_parser = SentenceSplitter(
-        chunk_size=chunk_size,
-        chunk_overlap=chunk_overlap,
-        separator=" ",
-        paragraph_separator="\n\n",
-    )
-
-    all_texts = []
-    for doc in documents:
-        nodes = node_parser.get_nodes_from_documents([doc])
-        if nodes:
-            all_texts.extend(node.get_content() for node in nodes)
-
-    return all_texts

apps/browser_rag.py

@@ -10,7 +10,8 @@ from pathlib import Path
 # Add parent directory to path for imports
 sys.path.insert(0, str(Path(__file__).parent))
 
-from base_rag_example import BaseRAGExample, create_text_chunks
+from base_rag_example import BaseRAGExample
+from chunking import create_text_chunks
 
 from .history_data.history import ChromeHistoryReader
 

apps/chatgpt_data/chatgpt_reader.py

@@ -0,0 +1,413 @@
+"""
+ChatGPT export data reader.
+
+Reads and processes ChatGPT export data from chat.html files.
+"""
+
+import re
+from pathlib import Path
+from typing import Any
+from zipfile import ZipFile
+
+from bs4 import BeautifulSoup
+from llama_index.core import Document
+from llama_index.core.readers.base import BaseReader
+
+
+class ChatGPTReader(BaseReader):
+    """
+    ChatGPT export data reader.
+
+    Reads ChatGPT conversation data from exported chat.html files or zip archives.
+    Processes conversations into structured documents with metadata.
+    """
+
+    def __init__(self, concatenate_conversations: bool = True) -> None:
+        """
+        Initialize.
+
+        Args:
+            concatenate_conversations: Whether to concatenate messages within conversations for better context
+        """
+        try:
+            from bs4 import BeautifulSoup  # noqa
+        except ImportError:
+            raise ImportError("`beautifulsoup4` package not found: `pip install beautifulsoup4`")
+
+        self.concatenate_conversations = concatenate_conversations
+
+    def _extract_html_from_zip(self, zip_path: Path) -> str | None:
+        """
+        Extract chat.html from ChatGPT export zip file.
+
+        Args:
+            zip_path: Path to the ChatGPT export zip file
+
+        Returns:
+            HTML content as string, or None if not found
+        """
+        try:
+            with ZipFile(zip_path, "r") as zip_file:
+                # Look for chat.html or conversations.html
+                html_files = [
+                    f
+                    for f in zip_file.namelist()
+                    if f.endswith(".html") and ("chat" in f.lower() or "conversation" in f.lower())
+                ]
+
+                if not html_files:
+                    print(f"No HTML chat file found in {zip_path}")
+                    return None
+
+                # Use the first HTML file found
+                html_file = html_files[0]
+                print(f"Found HTML file: {html_file}")
+
+                with zip_file.open(html_file) as f:
+                    return f.read().decode("utf-8", errors="ignore")
+
+        except Exception as e:
+            print(f"Error extracting HTML from zip {zip_path}: {e}")
+            return None
+
+    def _parse_chatgpt_html(self, html_content: str) -> list[dict]:
+        """
+        Parse ChatGPT HTML export to extract conversations.
+
+        Args:
+            html_content: HTML content from ChatGPT export
+
+        Returns:
+            List of conversation dictionaries
+        """
+        soup = BeautifulSoup(html_content, "html.parser")
+        conversations = []
+
+        # Try different possible structures for ChatGPT exports
+        # Structure 1: Look for conversation containers
+        conversation_containers = soup.find_all(
+            ["div", "section"], class_=re.compile(r"conversation|chat", re.I)
+        )
+
+        if not conversation_containers:
+            # Structure 2: Look for message containers directly
+            conversation_containers = [soup]  # Use the entire document as one conversation
+
+        for container in conversation_containers:
+            conversation = self._extract_conversation_from_container(container)
+            if conversation and conversation.get("messages"):
+                conversations.append(conversation)
+
+        # If no structured conversations found, try to extract all text as one conversation
+        if not conversations:
+            all_text = soup.get_text(separator="\n", strip=True)
+            if all_text:
+                conversations.append(
+                    {
+                        "title": "ChatGPT Conversation",
+                        "messages": [{"role": "mixed", "content": all_text, "timestamp": None}],
+                        "timestamp": None,
+                    }
+                )
+
+        return conversations
+
+    def _extract_conversation_from_container(self, container) -> dict | None:
+        """
+        Extract conversation data from a container element.
+
+        Args:
+            container: BeautifulSoup element containing conversation
+
+        Returns:
+            Dictionary with conversation data or None
+        """
+        messages = []
+
+        # Look for message elements with various possible structures
+        message_selectors = ['[class*="message"]', '[class*="chat"]', "[data-message]", "p", "div"]
+
+        for selector in message_selectors:
+            message_elements = container.select(selector)
+            if message_elements:
+                break
+        else:
+            message_elements = []
+
+        # If no structured messages found, treat the entire container as one message
+        if not message_elements:
+            text_content = container.get_text(separator="\n", strip=True)
+            if text_content:
+                messages.append({"role": "mixed", "content": text_content, "timestamp": None})
+        else:
+            for element in message_elements:
+                message = self._extract_message_from_element(element)
+                if message:
+                    messages.append(message)
+
+        if not messages:
+            return None
+
+        # Try to extract conversation title
+        title_element = container.find(["h1", "h2", "h3", "title"])
+        title = title_element.get_text(strip=True) if title_element else "ChatGPT Conversation"
+
+        # Try to extract timestamp from various possible locations
+        timestamp = self._extract_timestamp_from_container(container)
+
+        return {"title": title, "messages": messages, "timestamp": timestamp}
+
+    def _extract_message_from_element(self, element) -> dict | None:
+        """
+        Extract message data from an element.
+
+        Args:
+            element: BeautifulSoup element containing message
+
+        Returns:
+            Dictionary with message data or None
+        """
+        text_content = element.get_text(separator=" ", strip=True)
+
+        # Skip empty or very short messages
+        if not text_content or len(text_content.strip()) < 3:
+            return None
+
+        # Try to determine role (user/assistant) from class names or content
+        role = "mixed"  # Default role
+
+        class_names = " ".join(element.get("class", [])).lower()
+        if "user" in class_names or "human" in class_names:
+            role = "user"
+        elif "assistant" in class_names or "ai" in class_names or "gpt" in class_names:
+            role = "assistant"
+        elif text_content.lower().startswith(("you:", "user:", "me:")):
+            role = "user"
+            text_content = re.sub(r"^(you|user|me):\s*", "", text_content, flags=re.IGNORECASE)
+        elif text_content.lower().startswith(("chatgpt:", "assistant:", "ai:")):
+            role = "assistant"
+            text_content = re.sub(
+                r"^(chatgpt|assistant|ai):\s*", "", text_content, flags=re.IGNORECASE
+            )
+
+        # Try to extract timestamp
+        timestamp = self._extract_timestamp_from_element(element)
+
+        return {"role": role, "content": text_content, "timestamp": timestamp}
+
+    def _extract_timestamp_from_element(self, element) -> str | None:
+        """Extract timestamp from element."""
+        # Look for timestamp in various attributes and child elements
+        timestamp_attrs = ["data-timestamp", "timestamp", "datetime"]
+        for attr in timestamp_attrs:
+            if element.get(attr):
+                return element.get(attr)
+
+        # Look for time elements
+        time_element = element.find("time")
+        if time_element:
+            return time_element.get("datetime") or time_element.get_text(strip=True)
+
+        # Look for date-like text patterns
+        text = element.get_text()
+        date_patterns = [r"\d{4}-\d{2}-\d{2}", r"\d{1,2}/\d{1,2}/\d{4}", r"\w+ \d{1,2}, \d{4}"]
+
+        for pattern in date_patterns:
+            match = re.search(pattern, text)
+            if match:
+                return match.group()
+
+        return None
+
+    def _extract_timestamp_from_container(self, container) -> str | None:
+        """Extract timestamp from conversation container."""
+        return self._extract_timestamp_from_element(container)
+
+    def _create_concatenated_content(self, conversation: dict) -> str:
+        """
+        Create concatenated content from conversation messages.
+
+        Args:
+            conversation: Dictionary containing conversation data
+
+        Returns:
+            Formatted concatenated content
+        """
+        title = conversation.get("title", "ChatGPT Conversation")
+        messages = conversation.get("messages", [])
+        timestamp = conversation.get("timestamp", "Unknown")
+
+        # Build message content
+        message_parts = []
+        for message in messages:
+            role = message.get("role", "mixed")
+            content = message.get("content", "")
+            msg_timestamp = message.get("timestamp", "")
+
+            if role == "user":
+                prefix = "[You]"
+            elif role == "assistant":
+                prefix = "[ChatGPT]"
+            else:
+                prefix = "[Message]"
+
+            # Add timestamp if available
+            if msg_timestamp:
+                prefix += f" ({msg_timestamp})"
+
+            message_parts.append(f"{prefix}: {content}")
+
+        concatenated_text = "\n\n".join(message_parts)
+
+        # Create final document content
+        doc_content = f"""Conversation: {title}
+Date: {timestamp}
+Messages ({len(messages)} messages):
+
+{concatenated_text}
+"""
+        return doc_content
+
+    def load_data(self, input_dir: str | None = None, **load_kwargs: Any) -> list[Document]:
+        """
+        Load ChatGPT export data.
+
+        Args:
+            input_dir: Directory containing ChatGPT export files or path to specific file
+            **load_kwargs:
+                max_count (int): Maximum number of conversations to process
+                chatgpt_export_path (str): Specific path to ChatGPT export file/directory
+                include_metadata (bool): Whether to include metadata in documents
+        """
+        docs: list[Document] = []
+        max_count = load_kwargs.get("max_count", -1)
+        chatgpt_export_path = load_kwargs.get("chatgpt_export_path", input_dir)
+        include_metadata = load_kwargs.get("include_metadata", True)
+
+        if not chatgpt_export_path:
+            print("No ChatGPT export path provided")
+            return docs
+
+        export_path = Path(chatgpt_export_path)
+
+        if not export_path.exists():
+            print(f"ChatGPT export path not found: {export_path}")
+            return docs
+
+        html_content = None
+
+        # Handle different input types
+        if export_path.is_file():
+            if export_path.suffix.lower() == ".zip":
+                # Extract HTML from zip file
+                html_content = self._extract_html_from_zip(export_path)
+            elif export_path.suffix.lower() == ".html":
+                # Read HTML file directly
+                try:
+                    with open(export_path, encoding="utf-8", errors="ignore") as f:
+                        html_content = f.read()
+                except Exception as e:
+                    print(f"Error reading HTML file {export_path}: {e}")
+                    return docs
+            else:
+                print(f"Unsupported file type: {export_path.suffix}")
+                return docs
+
+        elif export_path.is_dir():
+            # Look for HTML files in directory
+            html_files = list(export_path.glob("*.html"))
+            zip_files = list(export_path.glob("*.zip"))
+
+            if html_files:
+                # Use first HTML file found
+                html_file = html_files[0]
+                print(f"Found HTML file: {html_file}")
+                try:
+                    with open(html_file, encoding="utf-8", errors="ignore") as f:
+                        html_content = f.read()
+                except Exception as e:
+                    print(f"Error reading HTML file {html_file}: {e}")
+                    return docs
+
+            elif zip_files:
+                # Use first zip file found
+                zip_file = zip_files[0]
+                print(f"Found zip file: {zip_file}")
+                html_content = self._extract_html_from_zip(zip_file)
+
+            else:
+                print(f"No HTML or zip files found in {export_path}")
+                return docs
+
+        if not html_content:
+            print("No HTML content found to process")
+            return docs
+
+        # Parse conversations from HTML
+        print("Parsing ChatGPT conversations from HTML...")
+        conversations = self._parse_chatgpt_html(html_content)
+
+        if not conversations:
+            print("No conversations found in HTML content")
+            return docs
+
+        print(f"Found {len(conversations)} conversations")
+
+        # Process conversations into documents
+        count = 0
+        for conversation in conversations:
+            if max_count > 0 and count >= max_count:
+                break
+
+            if self.concatenate_conversations:
+                # Create one document per conversation with concatenated messages
+                doc_content = self._create_concatenated_content(conversation)
+
+                metadata = {}
+                if include_metadata:
+                    metadata = {
+                        "title": conversation.get("title", "ChatGPT Conversation"),
+                        "timestamp": conversation.get("timestamp", "Unknown"),
+                        "message_count": len(conversation.get("messages", [])),
+                        "source": "ChatGPT Export",
+                    }
+
+                doc = Document(text=doc_content, metadata=metadata)
+                docs.append(doc)
+                count += 1
+
+            else:
+                # Create separate documents for each message
+                for message in conversation.get("messages", []):
+                    if max_count > 0 and count >= max_count:
+                        break
+
+                    role = message.get("role", "mixed")
+                    content = message.get("content", "")
+                    msg_timestamp = message.get("timestamp", "")
+
+                    if not content.strip():
+                        continue
+
+                    # Create document content with context
+                    doc_content = f"""Conversation: {conversation.get("title", "ChatGPT Conversation")}
+Role: {role}
+Timestamp: {msg_timestamp or conversation.get("timestamp", "Unknown")}
+Message: {content}
+"""
+
+                    metadata = {}
+                    if include_metadata:
+                        metadata = {
+                            "conversation_title": conversation.get("title", "ChatGPT Conversation"),
+                            "role": role,
+                            "timestamp": msg_timestamp or conversation.get("timestamp", "Unknown"),
+                            "source": "ChatGPT Export",
+                        }
+
+                    doc = Document(text=doc_content, metadata=metadata)
+                    docs.append(doc)
+                    count += 1
+
+        print(f"Created {len(docs)} documents from ChatGPT export")
+        return docs

apps/chatgpt_rag.py

@@ -0,0 +1,186 @@
+"""
+ChatGPT RAG example using the unified interface.
+Supports ChatGPT export data from chat.html files.
+"""
+
+import sys
+from pathlib import Path
+
+# Add parent directory to path for imports
+sys.path.insert(0, str(Path(__file__).parent))
+
+from base_rag_example import BaseRAGExample
+from chunking import create_text_chunks
+
+from .chatgpt_data.chatgpt_reader import ChatGPTReader
+
+
+class ChatGPTRAG(BaseRAGExample):
+    """RAG example for ChatGPT conversation data."""
+
+    def __init__(self):
+        # Set default values BEFORE calling super().__init__
+        self.max_items_default = -1  # Process all conversations by default
+        self.embedding_model_default = (
+            "sentence-transformers/all-MiniLM-L6-v2"  # Fast 384-dim model
+        )
+
+        super().__init__(
+            name="ChatGPT",
+            description="Process and query ChatGPT conversation exports with LEANN",
+            default_index_name="chatgpt_conversations_index",
+        )
+
+    def _add_specific_arguments(self, parser):
+        """Add ChatGPT-specific arguments."""
+        chatgpt_group = parser.add_argument_group("ChatGPT Parameters")
+        chatgpt_group.add_argument(
+            "--export-path",
+            type=str,
+            default="./chatgpt_export",
+            help="Path to ChatGPT export file (.zip or .html) or directory containing exports (default: ./chatgpt_export)",
+        )
+        chatgpt_group.add_argument(
+            "--concatenate-conversations",
+            action="store_true",
+            default=True,
+            help="Concatenate messages within conversations for better context (default: True)",
+        )
+        chatgpt_group.add_argument(
+            "--separate-messages",
+            action="store_true",
+            help="Process each message as a separate document (overrides --concatenate-conversations)",
+        )
+        chatgpt_group.add_argument(
+            "--chunk-size", type=int, default=512, help="Text chunk size (default: 512)"
+        )
+        chatgpt_group.add_argument(
+            "--chunk-overlap", type=int, default=128, help="Text chunk overlap (default: 128)"
+        )
+
+    def _find_chatgpt_exports(self, export_path: Path) -> list[Path]:
+        """
+        Find ChatGPT export files in the given path.
+
+        Args:
+            export_path: Path to search for exports
+
+        Returns:
+            List of paths to ChatGPT export files
+        """
+        export_files = []
+
+        if export_path.is_file():
+            if export_path.suffix.lower() in [".zip", ".html"]:
+                export_files.append(export_path)
+        elif export_path.is_dir():
+            # Look for zip and html files
+            export_files.extend(export_path.glob("*.zip"))
+            export_files.extend(export_path.glob("*.html"))
+
+        return export_files
+
+    async def load_data(self, args) -> list[str]:
+        """Load ChatGPT export data and convert to text chunks."""
+        export_path = Path(args.export_path)
+
+        if not export_path.exists():
+            print(f"ChatGPT export path not found: {export_path}")
+            print(
+                "Please ensure you have exported your ChatGPT data and placed it in the correct location."
+            )
+            print("\nTo export your ChatGPT data:")
+            print("1. Sign in to ChatGPT")
+            print("2. Click on your profile icon → Settings → Data Controls")
+            print("3. Click 'Export' under Export Data")
+            print("4. Download the zip file from the email link")
+            print("5. Extract or place the file/directory at the specified path")
+            return []
+
+        # Find export files
+        export_files = self._find_chatgpt_exports(export_path)
+
+        if not export_files:
+            print(f"No ChatGPT export files (.zip or .html) found in: {export_path}")
+            return []
+
+        print(f"Found {len(export_files)} ChatGPT export files")
+
+        # Create reader with appropriate settings
+        concatenate = args.concatenate_conversations and not args.separate_messages
+        reader = ChatGPTReader(concatenate_conversations=concatenate)
+
+        # Process each export file
+        all_documents = []
+        total_processed = 0
+
+        for i, export_file in enumerate(export_files):
+            print(f"\nProcessing export file {i + 1}/{len(export_files)}: {export_file.name}")
+
+            try:
+                # Apply max_items limit per file
+                max_per_file = -1
+                if args.max_items > 0:
+                    remaining = args.max_items - total_processed
+                    if remaining <= 0:
+                        break
+                    max_per_file = remaining
+
+                # Load conversations
+                documents = reader.load_data(
+                    chatgpt_export_path=str(export_file),
+                    max_count=max_per_file,
+                    include_metadata=True,
+                )
+
+                if documents:
+                    all_documents.extend(documents)
+                    total_processed += len(documents)
+                    print(f"Processed {len(documents)} conversations from this file")
+                else:
+                    print(f"No conversations loaded from {export_file}")
+
+            except Exception as e:
+                print(f"Error processing {export_file}: {e}")
+                continue
+
+        if not all_documents:
+            print("No conversations found to process!")
+            print("\nTroubleshooting:")
+            print("- Ensure the export file is a valid ChatGPT export")
+            print("- Check that the HTML file contains conversation data")
+            print("- Try extracting the zip file and pointing to the HTML file directly")
+            return []
+
+        print(f"\nTotal conversations processed: {len(all_documents)}")
+        print("Now starting to split into text chunks... this may take some time")
+
+        # Convert to text chunks
+        all_texts = create_text_chunks(
+            all_documents, chunk_size=args.chunk_size, chunk_overlap=args.chunk_overlap
+        )
+
+        print(f"Created {len(all_texts)} text chunks from {len(all_documents)} conversations")
+        return all_texts
+
+
+if __name__ == "__main__":
+    import asyncio
+
+    # Example queries for ChatGPT RAG
+    print("\n🤖 ChatGPT RAG Example")
+    print("=" * 50)
+    print("\nExample queries you can try:")
+    print("- 'What did I ask about Python programming?'")
+    print("- 'Show me conversations about machine learning'")
+    print("- 'Find discussions about travel planning'")
+    print("- 'What advice did ChatGPT give me about career development?'")
+    print("- 'Search for conversations about cooking recipes'")
+    print("\nTo get started:")
+    print("1. Export your ChatGPT data from Settings → Data Controls → Export")
+    print("2. Place the downloaded zip file or extracted HTML in ./chatgpt_export/")
+    print("3. Run this script to build your personal ChatGPT knowledge base!")
+    print("\nOr run without --query for interactive mode\n")
+
+    rag = ChatGPTRAG()
+    asyncio.run(rag.run())

apps/chunking/__init__.py

@@ -0,0 +1,44 @@
+"""Unified chunking utilities facade.
+
+This module re-exports the packaged utilities from `leann.chunking_utils` so
+that both repo apps (importing `chunking`) and installed wheels share one
+single implementation. When running from the repo without installation, it
+adds the `packages/leann-core/src` directory to `sys.path` as a fallback.
+"""
+
+import sys
+from pathlib import Path
+
+try:
+    from leann.chunking_utils import (
+        CODE_EXTENSIONS,
+        create_ast_chunks,
+        create_text_chunks,
+        create_traditional_chunks,
+        detect_code_files,
+        get_language_from_extension,
+    )
+except Exception:  # pragma: no cover - best-effort fallback for dev environment
+    repo_root = Path(__file__).resolve().parents[2]
+    leann_src = repo_root / "packages" / "leann-core" / "src"
+    if leann_src.exists():
+        sys.path.insert(0, str(leann_src))
+        from leann.chunking_utils import (
+            CODE_EXTENSIONS,
+            create_ast_chunks,
+            create_text_chunks,
+            create_traditional_chunks,
+            detect_code_files,
+            get_language_from_extension,
+        )
+    else:
+        raise
+
+__all__ = [
+    "CODE_EXTENSIONS",
+    "create_ast_chunks",
+    "create_text_chunks",
+    "create_traditional_chunks",
+    "detect_code_files",
+    "get_language_from_extension",
+]

apps/claude_data/claude_reader.py

@@ -0,0 +1,420 @@
+"""
+Claude export data reader.
+
+Reads and processes Claude conversation data from exported JSON files.
+"""
+
+import json
+from pathlib import Path
+from typing import Any
+from zipfile import ZipFile
+
+from llama_index.core import Document
+from llama_index.core.readers.base import BaseReader
+
+
+class ClaudeReader(BaseReader):
+    """
+    Claude export data reader.
+
+    Reads Claude conversation data from exported JSON files or zip archives.
+    Processes conversations into structured documents with metadata.
+    """
+
+    def __init__(self, concatenate_conversations: bool = True) -> None:
+        """
+        Initialize.
+
+        Args:
+            concatenate_conversations: Whether to concatenate messages within conversations for better context
+        """
+        self.concatenate_conversations = concatenate_conversations
+
+    def _extract_json_from_zip(self, zip_path: Path) -> list[str]:
+        """
+        Extract JSON files from Claude export zip file.
+
+        Args:
+            zip_path: Path to the Claude export zip file
+
+        Returns:
+            List of JSON content strings, or empty list if not found
+        """
+        json_contents = []
+        try:
+            with ZipFile(zip_path, "r") as zip_file:
+                # Look for JSON files
+                json_files = [f for f in zip_file.namelist() if f.endswith(".json")]
+
+                if not json_files:
+                    print(f"No JSON files found in {zip_path}")
+                    return []
+
+                print(f"Found {len(json_files)} JSON files in archive")
+
+                for json_file in json_files:
+                    with zip_file.open(json_file) as f:
+                        content = f.read().decode("utf-8", errors="ignore")
+                        json_contents.append(content)
+
+        except Exception as e:
+            print(f"Error extracting JSON from zip {zip_path}: {e}")
+
+        return json_contents
+
+    def _parse_claude_json(self, json_content: str) -> list[dict]:
+        """
+        Parse Claude JSON export to extract conversations.
+
+        Args:
+            json_content: JSON content from Claude export
+
+        Returns:
+            List of conversation dictionaries
+        """
+        try:
+            data = json.loads(json_content)
+        except json.JSONDecodeError as e:
+            print(f"Error parsing JSON: {e}")
+            return []
+
+        conversations = []
+
+        # Handle different possible JSON structures
+        if isinstance(data, list):
+            # If data is a list of conversations
+            for item in data:
+                conversation = self._extract_conversation_from_json(item)
+                if conversation:
+                    conversations.append(conversation)
+        elif isinstance(data, dict):
+            # Check for common structures
+            if "conversations" in data:
+                # Structure: {"conversations": [...]}
+                for item in data["conversations"]:
+                    conversation = self._extract_conversation_from_json(item)
+                    if conversation:
+                        conversations.append(conversation)
+            elif "messages" in data:
+                # Single conversation with messages
+                conversation = self._extract_conversation_from_json(data)
+                if conversation:
+                    conversations.append(conversation)
+            else:
+                # Try to treat the whole object as a conversation
+                conversation = self._extract_conversation_from_json(data)
+                if conversation:
+                    conversations.append(conversation)
+
+        return conversations
+
+    def _extract_conversation_from_json(self, conv_data: dict) -> dict | None:
+        """
+        Extract conversation data from a JSON object.
+
+        Args:
+            conv_data: Dictionary containing conversation data
+
+        Returns:
+            Dictionary with conversation data or None
+        """
+        if not isinstance(conv_data, dict):
+            return None
+
+        messages = []
+
+        # Look for messages in various possible structures
+        message_sources = []
+        if "messages" in conv_data:
+            message_sources = conv_data["messages"]
+        elif "chat" in conv_data:
+            message_sources = conv_data["chat"]
+        elif "conversation" in conv_data:
+            message_sources = conv_data["conversation"]
+        else:
+            # If no clear message structure, try to extract from the object itself
+            if "content" in conv_data and "role" in conv_data:
+                message_sources = [conv_data]
+
+        for msg_data in message_sources:
+            message = self._extract_message_from_json(msg_data)
+            if message:
+                messages.append(message)
+
+        if not messages:
+            return None
+
+        # Extract conversation metadata
+        title = self._extract_title_from_conversation(conv_data, messages)
+        timestamp = self._extract_timestamp_from_conversation(conv_data)
+
+        return {"title": title, "messages": messages, "timestamp": timestamp}
+
+    def _extract_message_from_json(self, msg_data: dict) -> dict | None:
+        """
+        Extract message data from a JSON message object.
+
+        Args:
+            msg_data: Dictionary containing message data
+
+        Returns:
+            Dictionary with message data or None
+        """
+        if not isinstance(msg_data, dict):
+            return None
+
+        # Extract content from various possible fields
+        content = ""
+        content_fields = ["content", "text", "message", "body"]
+        for field in content_fields:
+            if msg_data.get(field):
+                content = str(msg_data[field])
+                break
+
+        if not content or len(content.strip()) < 3:
+            return None
+
+        # Extract role (user/assistant/human/ai/claude)
+        role = "mixed"  # Default role
+        role_fields = ["role", "sender", "from", "author", "type"]
+        for field in role_fields:
+            if msg_data.get(field):
+                role_value = str(msg_data[field]).lower()
+                if role_value in ["user", "human", "person"]:
+                    role = "user"
+                elif role_value in ["assistant", "ai", "claude", "bot"]:
+                    role = "assistant"
+                break
+
+        # Extract timestamp
+        timestamp = self._extract_timestamp_from_message(msg_data)
+
+        return {"role": role, "content": content, "timestamp": timestamp}
+
+    def _extract_timestamp_from_message(self, msg_data: dict) -> str | None:
+        """Extract timestamp from message data."""
+        timestamp_fields = ["timestamp", "created_at", "date", "time"]
+        for field in timestamp_fields:
+            if msg_data.get(field):
+                return str(msg_data[field])
+        return None
+
+    def _extract_timestamp_from_conversation(self, conv_data: dict) -> str | None:
+        """Extract timestamp from conversation data."""
+        timestamp_fields = ["timestamp", "created_at", "date", "updated_at", "last_updated"]
+        for field in timestamp_fields:
+            if conv_data.get(field):
+                return str(conv_data[field])
+        return None
+
+    def _extract_title_from_conversation(self, conv_data: dict, messages: list) -> str:
+        """Extract or generate title for conversation."""
+        # Try to find explicit title
+        title_fields = ["title", "name", "subject", "topic"]
+        for field in title_fields:
+            if conv_data.get(field):
+                return str(conv_data[field])
+
+        # Generate title from first user message
+        for message in messages:
+            if message.get("role") == "user":
+                content = message.get("content", "")
+                if content:
+                    # Use first 50 characters as title
+                    title = content[:50].strip()
+                    if len(content) > 50:
+                        title += "..."
+                    return title
+
+        return "Claude Conversation"
+
+    def _create_concatenated_content(self, conversation: dict) -> str:
+        """
+        Create concatenated content from conversation messages.
+
+        Args:
+            conversation: Dictionary containing conversation data
+
+        Returns:
+            Formatted concatenated content
+        """
+        title = conversation.get("title", "Claude Conversation")
+        messages = conversation.get("messages", [])
+        timestamp = conversation.get("timestamp", "Unknown")
+
+        # Build message content
+        message_parts = []
+        for message in messages:
+            role = message.get("role", "mixed")
+            content = message.get("content", "")
+            msg_timestamp = message.get("timestamp", "")
+
+            if role == "user":
+                prefix = "[You]"
+            elif role == "assistant":
+                prefix = "[Claude]"
+            else:
+                prefix = "[Message]"
+
+            # Add timestamp if available
+            if msg_timestamp:
+                prefix += f" ({msg_timestamp})"
+
+            message_parts.append(f"{prefix}: {content}")
+
+        concatenated_text = "\n\n".join(message_parts)
+
+        # Create final document content
+        doc_content = f"""Conversation: {title}
+Date: {timestamp}
+Messages ({len(messages)} messages):
+
+{concatenated_text}
+"""
+        return doc_content
+
+    def load_data(self, input_dir: str | None = None, **load_kwargs: Any) -> list[Document]:
+        """
+        Load Claude export data.
+
+        Args:
+            input_dir: Directory containing Claude export files or path to specific file
+            **load_kwargs:
+                max_count (int): Maximum number of conversations to process
+                claude_export_path (str): Specific path to Claude export file/directory
+                include_metadata (bool): Whether to include metadata in documents
+        """
+        docs: list[Document] = []
+        max_count = load_kwargs.get("max_count", -1)
+        claude_export_path = load_kwargs.get("claude_export_path", input_dir)
+        include_metadata = load_kwargs.get("include_metadata", True)
+
+        if not claude_export_path:
+            print("No Claude export path provided")
+            return docs
+
+        export_path = Path(claude_export_path)
+
+        if not export_path.exists():
+            print(f"Claude export path not found: {export_path}")
+            return docs
+
+        json_contents = []
+
+        # Handle different input types
+        if export_path.is_file():
+            if export_path.suffix.lower() == ".zip":
+                # Extract JSON from zip file
+                json_contents = self._extract_json_from_zip(export_path)
+            elif export_path.suffix.lower() == ".json":
+                # Read JSON file directly
+                try:
+                    with open(export_path, encoding="utf-8", errors="ignore") as f:
+                        json_contents.append(f.read())
+                except Exception as e:
+                    print(f"Error reading JSON file {export_path}: {e}")
+                    return docs
+            else:
+                print(f"Unsupported file type: {export_path.suffix}")
+                return docs
+
+        elif export_path.is_dir():
+            # Look for JSON files in directory
+            json_files = list(export_path.glob("*.json"))
+            zip_files = list(export_path.glob("*.zip"))
+
+            if json_files:
+                print(f"Found {len(json_files)} JSON files in directory")
+                for json_file in json_files:
+                    try:
+                        with open(json_file, encoding="utf-8", errors="ignore") as f:
+                            json_contents.append(f.read())
+                    except Exception as e:
+                        print(f"Error reading JSON file {json_file}: {e}")
+                        continue
+
+            if zip_files:
+                print(f"Found {len(zip_files)} ZIP files in directory")
+                for zip_file in zip_files:
+                    zip_contents = self._extract_json_from_zip(zip_file)
+                    json_contents.extend(zip_contents)
+
+            if not json_files and not zip_files:
+                print(f"No JSON or ZIP files found in {export_path}")
+                return docs
+
+        if not json_contents:
+            print("No JSON content found to process")
+            return docs
+
+        # Parse conversations from JSON content
+        print("Parsing Claude conversations from JSON...")
+        all_conversations = []
+        for json_content in json_contents:
+            conversations = self._parse_claude_json(json_content)
+            all_conversations.extend(conversations)
+
+        if not all_conversations:
+            print("No conversations found in JSON content")
+            return docs
+
+        print(f"Found {len(all_conversations)} conversations")
+
+        # Process conversations into documents
+        count = 0
+        for conversation in all_conversations:
+            if max_count > 0 and count >= max_count:
+                break
+
+            if self.concatenate_conversations:
+                # Create one document per conversation with concatenated messages
+                doc_content = self._create_concatenated_content(conversation)
+
+                metadata = {}
+                if include_metadata:
+                    metadata = {
+                        "title": conversation.get("title", "Claude Conversation"),
+                        "timestamp": conversation.get("timestamp", "Unknown"),
+                        "message_count": len(conversation.get("messages", [])),
+                        "source": "Claude Export",
+                    }
+
+                doc = Document(text=doc_content, metadata=metadata)
+                docs.append(doc)
+                count += 1
+
+            else:
+                # Create separate documents for each message
+                for message in conversation.get("messages", []):
+                    if max_count > 0 and count >= max_count:
+                        break
+
+                    role = message.get("role", "mixed")
+                    content = message.get("content", "")
+                    msg_timestamp = message.get("timestamp", "")
+
+                    if not content.strip():
+                        continue
+
+                    # Create document content with context
+                    doc_content = f"""Conversation: {conversation.get("title", "Claude Conversation")}
+Role: {role}
+Timestamp: {msg_timestamp or conversation.get("timestamp", "Unknown")}
+Message: {content}
+"""
+
+                    metadata = {}
+                    if include_metadata:
+                        metadata = {
+                            "conversation_title": conversation.get("title", "Claude Conversation"),
+                            "role": role,
+                            "timestamp": msg_timestamp or conversation.get("timestamp", "Unknown"),
+                            "source": "Claude Export",
+                        }
+
+                    doc = Document(text=doc_content, metadata=metadata)
+                    docs.append(doc)
+                    count += 1
+
+        print(f"Created {len(docs)} documents from Claude export")
+        return docs

apps/claude_rag.py

@@ -0,0 +1,189 @@
+"""
+Claude RAG example using the unified interface.
+Supports Claude export data from JSON files.
+"""
+
+import sys
+from pathlib import Path
+
+# Add parent directory to path for imports
+sys.path.insert(0, str(Path(__file__).parent))
+
+from base_rag_example import BaseRAGExample
+from chunking import create_text_chunks
+
+from .claude_data.claude_reader import ClaudeReader
+
+
+class ClaudeRAG(BaseRAGExample):
+    """RAG example for Claude conversation data."""
+
+    def __init__(self):
+        # Set default values BEFORE calling super().__init__
+        self.max_items_default = -1  # Process all conversations by default
+        self.embedding_model_default = (
+            "sentence-transformers/all-MiniLM-L6-v2"  # Fast 384-dim model
+        )
+
+        super().__init__(
+            name="Claude",
+            description="Process and query Claude conversation exports with LEANN",
+            default_index_name="claude_conversations_index",
+        )
+
+    def _add_specific_arguments(self, parser):
+        """Add Claude-specific arguments."""
+        claude_group = parser.add_argument_group("Claude Parameters")
+        claude_group.add_argument(
+            "--export-path",
+            type=str,
+            default="./claude_export",
+            help="Path to Claude export file (.json or .zip) or directory containing exports (default: ./claude_export)",
+        )
+        claude_group.add_argument(
+            "--concatenate-conversations",
+            action="store_true",
+            default=True,
+            help="Concatenate messages within conversations for better context (default: True)",
+        )
+        claude_group.add_argument(
+            "--separate-messages",
+            action="store_true",
+            help="Process each message as a separate document (overrides --concatenate-conversations)",
+        )
+        claude_group.add_argument(
+            "--chunk-size", type=int, default=512, help="Text chunk size (default: 512)"
+        )
+        claude_group.add_argument(
+            "--chunk-overlap", type=int, default=128, help="Text chunk overlap (default: 128)"
+        )
+
+    def _find_claude_exports(self, export_path: Path) -> list[Path]:
+        """
+        Find Claude export files in the given path.
+
+        Args:
+            export_path: Path to search for exports
+
+        Returns:
+            List of paths to Claude export files
+        """
+        export_files = []
+
+        if export_path.is_file():
+            if export_path.suffix.lower() in [".zip", ".json"]:
+                export_files.append(export_path)
+        elif export_path.is_dir():
+            # Look for zip and json files
+            export_files.extend(export_path.glob("*.zip"))
+            export_files.extend(export_path.glob("*.json"))
+
+        return export_files
+
+    async def load_data(self, args) -> list[str]:
+        """Load Claude export data and convert to text chunks."""
+        export_path = Path(args.export_path)
+
+        if not export_path.exists():
+            print(f"Claude export path not found: {export_path}")
+            print(
+                "Please ensure you have exported your Claude data and placed it in the correct location."
+            )
+            print("\nTo export your Claude data:")
+            print("1. Open Claude in your browser")
+            print("2. Look for export/download options in settings or conversation menu")
+            print("3. Download the conversation data (usually in JSON format)")
+            print("4. Place the file/directory at the specified path")
+            print(
+                "\nNote: Claude export methods may vary. Check Claude's help documentation for current instructions."
+            )
+            return []
+
+        # Find export files
+        export_files = self._find_claude_exports(export_path)
+
+        if not export_files:
+            print(f"No Claude export files (.json or .zip) found in: {export_path}")
+            return []
+
+        print(f"Found {len(export_files)} Claude export files")
+
+        # Create reader with appropriate settings
+        concatenate = args.concatenate_conversations and not args.separate_messages
+        reader = ClaudeReader(concatenate_conversations=concatenate)
+
+        # Process each export file
+        all_documents = []
+        total_processed = 0
+
+        for i, export_file in enumerate(export_files):
+            print(f"\nProcessing export file {i + 1}/{len(export_files)}: {export_file.name}")
+
+            try:
+                # Apply max_items limit per file
+                max_per_file = -1
+                if args.max_items > 0:
+                    remaining = args.max_items - total_processed
+                    if remaining <= 0:
+                        break
+                    max_per_file = remaining
+
+                # Load conversations
+                documents = reader.load_data(
+                    claude_export_path=str(export_file),
+                    max_count=max_per_file,
+                    include_metadata=True,
+                )
+
+                if documents:
+                    all_documents.extend(documents)
+                    total_processed += len(documents)
+                    print(f"Processed {len(documents)} conversations from this file")
+                else:
+                    print(f"No conversations loaded from {export_file}")
+
+            except Exception as e:
+                print(f"Error processing {export_file}: {e}")
+                continue
+
+        if not all_documents:
+            print("No conversations found to process!")
+            print("\nTroubleshooting:")
+            print("- Ensure the export file is a valid Claude export")
+            print("- Check that the JSON file contains conversation data")
+            print("- Try using a different export format or method")
+            print("- Check Claude's documentation for current export procedures")
+            return []
+
+        print(f"\nTotal conversations processed: {len(all_documents)}")
+        print("Now starting to split into text chunks... this may take some time")
+
+        # Convert to text chunks
+        all_texts = create_text_chunks(
+            all_documents, chunk_size=args.chunk_size, chunk_overlap=args.chunk_overlap
+        )
+
+        print(f"Created {len(all_texts)} text chunks from {len(all_documents)} conversations")
+        return all_texts
+
+
+if __name__ == "__main__":
+    import asyncio
+
+    # Example queries for Claude RAG
+    print("\n🤖 Claude RAG Example")
+    print("=" * 50)
+    print("\nExample queries you can try:")
+    print("- 'What did I ask Claude about Python programming?'")
+    print("- 'Show me conversations about machine learning'")
+    print("- 'Find discussions about code optimization'")
+    print("- 'What advice did Claude give me about software design?'")
+    print("- 'Search for conversations about debugging techniques'")
+    print("\nTo get started:")
+    print("1. Export your Claude conversation data")
+    print("2. Place the JSON/ZIP file in ./claude_export/")
+    print("3. Run this script to build your personal Claude knowledge base!")
+    print("\nOr run without --query for interactive mode\n")
+
+    rag = ClaudeRAG()
+    asyncio.run(rag.run())

apps/code_rag.py

@@ -0,0 +1,211 @@
+"""
+Code RAG example using AST-aware chunking for optimal code understanding.
+Specialized for code repositories with automatic language detection and
+optimized chunking parameters.
+"""
+
+import sys
+from pathlib import Path
+
+# Add parent directory to path for imports
+sys.path.insert(0, str(Path(__file__).parent))
+
+from base_rag_example import BaseRAGExample
+from chunking import CODE_EXTENSIONS, create_text_chunks
+from llama_index.core import SimpleDirectoryReader
+
+
+class CodeRAG(BaseRAGExample):
+    """Specialized RAG example for code repositories with AST-aware chunking."""
+
+    def __init__(self):
+        super().__init__(
+            name="Code",
+            description="Process and query code repositories with AST-aware chunking",
+            default_index_name="code_index",
+        )
+        # Override defaults for code-specific usage
+        self.embedding_model_default = "facebook/contriever"  # Good for code
+        self.max_items_default = -1  # Process all code files by default
+
+    def _add_specific_arguments(self, parser):
+        """Add code-specific arguments."""
+        code_group = parser.add_argument_group("Code Repository Parameters")
+
+        code_group.add_argument(
+            "--repo-dir",
+            type=str,
+            default=".",
+            help="Code repository directory to index (default: current directory)",
+        )
+        code_group.add_argument(
+            "--include-extensions",
+            nargs="+",
+            default=list(CODE_EXTENSIONS.keys()),
+            help="File extensions to include (default: supported code extensions)",
+        )
+        code_group.add_argument(
+            "--exclude-dirs",
+            nargs="+",
+            default=[
+                ".git",
+                "__pycache__",
+                "node_modules",
+                "venv",
+                ".venv",
+                "build",
+                "dist",
+                "target",
+            ],
+            help="Directories to exclude from indexing",
+        )
+        code_group.add_argument(
+            "--max-file-size",
+            type=int,
+            default=1000000,  # 1MB
+            help="Maximum file size in bytes to process (default: 1MB)",
+        )
+        code_group.add_argument(
+            "--include-comments",
+            action="store_true",
+            help="Include comments in chunking (useful for documentation)",
+        )
+        code_group.add_argument(
+            "--preserve-imports",
+            action="store_true",
+            default=True,
+            help="Try to preserve import statements in chunks (default: True)",
+        )
+
+    async def load_data(self, args) -> list[str]:
+        """Load code files and convert to AST-aware chunks."""
+        print(f"🔍 Scanning code repository: {args.repo_dir}")
+        print(f"📁 Including extensions: {args.include_extensions}")
+        print(f"🚫 Excluding directories: {args.exclude_dirs}")
+
+        # Check if repository directory exists
+        repo_path = Path(args.repo_dir)
+        if not repo_path.exists():
+            raise ValueError(f"Repository directory not found: {args.repo_dir}")
+
+        # Load code files with filtering
+        reader_kwargs = {
+            "recursive": True,
+            "encoding": "utf-8",
+            "required_exts": args.include_extensions,
+            "exclude_hidden": True,
+        }
+
+        # Create exclusion filter
+        def file_filter(file_path: str) -> bool:
+            """Filter out unwanted files and directories."""
+            path = Path(file_path)
+
+            # Check file size
+            try:
+                if path.stat().st_size > args.max_file_size:
+                    print(f"⚠️ Skipping large file: {path.name} ({path.stat().st_size} bytes)")
+                    return False
+            except Exception:
+                return False
+
+            # Check if in excluded directory
+            for exclude_dir in args.exclude_dirs:
+                if exclude_dir in path.parts:
+                    return False
+
+            return True
+
+        try:
+            # Load documents with file filtering
+            documents = SimpleDirectoryReader(
+                args.repo_dir,
+                file_extractor=None,  # Use default extractors
+                **reader_kwargs,
+            ).load_data(show_progress=True)
+
+            # Apply custom filtering
+            filtered_docs = []
+            for doc in documents:
+                file_path = doc.metadata.get("file_path", "")
+                if file_filter(file_path):
+                    filtered_docs.append(doc)
+
+            documents = filtered_docs
+
+        except Exception as e:
+            print(f"❌ Error loading code files: {e}")
+            return []
+
+        if not documents:
+            print(
+                f"❌ No code files found in {args.repo_dir} with extensions {args.include_extensions}"
+            )
+            return []
+
+        print(f"✅ Loaded {len(documents)} code files")
+
+        # Show breakdown by language/extension
+        ext_counts = {}
+        for doc in documents:
+            file_path = doc.metadata.get("file_path", "")
+            if file_path:
+                ext = Path(file_path).suffix.lower()
+                ext_counts[ext] = ext_counts.get(ext, 0) + 1
+
+        print("📊 Files by extension:")
+        for ext, count in sorted(ext_counts.items()):
+            print(f"   {ext}: {count} files")
+
+        # Use AST-aware chunking by default for code
+        print(
+            f"🧠 Using AST-aware chunking (chunk_size: {args.ast_chunk_size}, overlap: {args.ast_chunk_overlap})"
+        )
+
+        all_texts = create_text_chunks(
+            documents,
+            chunk_size=256,  # Fallback for non-code files
+            chunk_overlap=64,
+            use_ast_chunking=True,  # Always use AST for code RAG
+            ast_chunk_size=args.ast_chunk_size,
+            ast_chunk_overlap=args.ast_chunk_overlap,
+            code_file_extensions=args.include_extensions,
+            ast_fallback_traditional=True,
+        )
+
+        # Apply max_items limit if specified
+        if args.max_items > 0 and len(all_texts) > args.max_items:
+            print(f"⏳ Limiting to {args.max_items} chunks (from {len(all_texts)})")
+            all_texts = all_texts[: args.max_items]
+
+        print(f"✅ Generated {len(all_texts)} code chunks")
+        return all_texts
+
+
+if __name__ == "__main__":
+    import asyncio
+
+    # Example queries for code RAG
+    print("\n💻 Code RAG Example")
+    print("=" * 50)
+    print("\nExample queries you can try:")
+    print("- 'How does the embedding computation work?'")
+    print("- 'What are the main classes in this codebase?'")
+    print("- 'Show me the search implementation'")
+    print("- 'How is error handling implemented?'")
+    print("- 'What design patterns are used?'")
+    print("- 'Explain the chunking logic'")
+    print("\n🚀 Features:")
+    print("- ✅ AST-aware chunking preserves code structure")
+    print("- ✅ Automatic language detection")
+    print("- ✅ Smart filtering of large files and common excludes")
+    print("- ✅ Optimized for code understanding")
+    print("\nUsage examples:")
+    print("  python -m apps.code_rag --repo-dir ./my_project")
+    print(
+        "  python -m apps.code_rag --include-extensions .py .js --query 'How does authentication work?'"
+    )
+    print("\nOr run without --query for interactive mode\n")
+
+    rag = CodeRAG()
+    asyncio.run(rag.run())

apps/document_rag.py

@@ -9,7 +9,8 @@ from pathlib import Path
 # Add parent directory to path for imports
 sys.path.insert(0, str(Path(__file__).parent))
 
-from base_rag_example import BaseRAGExample, create_text_chunks
+from base_rag_example import BaseRAGExample
+from chunking import create_text_chunks
 from llama_index.core import SimpleDirectoryReader
 
 
@@ -44,6 +45,11 @@ class DocumentRAG(BaseRAGExample):
         doc_group.add_argument(
             "--chunk-overlap", type=int, default=128, help="Text chunk overlap (default: 128)"
         )
+        doc_group.add_argument(
+            "--enable-code-chunking",
+            action="store_true",
+            help="Enable AST-aware chunking for code files in the data directory",
+        )
 
     async def load_data(self, args) -> list[str]:
         """Load documents and convert to text chunks."""
@@ -76,9 +82,22 @@ class DocumentRAG(BaseRAGExample):
 
         print(f"Loaded {len(documents)} documents")
 
-        # Convert to text chunks
+        # Determine chunking strategy
+        use_ast = args.enable_code_chunking or getattr(args, "use_ast_chunking", False)
+
+        if use_ast:
+            print("Using AST-aware chunking for code files")
+
+        # Convert to text chunks with optional AST support
         all_texts = create_text_chunks(
-            documents, chunk_size=args.chunk_size, chunk_overlap=args.chunk_overlap
+            documents,
+            chunk_size=args.chunk_size,
+            chunk_overlap=args.chunk_overlap,
+            use_ast_chunking=use_ast,
+            ast_chunk_size=getattr(args, "ast_chunk_size", 512),
+            ast_chunk_overlap=getattr(args, "ast_chunk_overlap", 64),
+            code_file_extensions=getattr(args, "code_file_extensions", None),
+            ast_fallback_traditional=getattr(args, "ast_fallback_traditional", True),
         )
 
         # Apply max_items limit if specified
@@ -102,6 +121,10 @@ if __name__ == "__main__":
     print(
         "- 'What is the problem of developing pan gu model Huawei meets? (盘古大模型开发中遇到什么问题?)'"
     )
+    print("\n🚀 NEW: Code-aware chunking available!")
+    print("- Use --enable-code-chunking to enable AST-aware chunking for code files")
+    print("- Supports Python, Java, C#, TypeScript files")
+    print("- Better semantic understanding of code structure")
     print("\nOr run without --query for interactive mode\n")
 
     rag = DocumentRAG()

apps/email_rag.py

@@ -9,7 +9,8 @@ from pathlib import Path
 # Add parent directory to path for imports
 sys.path.insert(0, str(Path(__file__).parent))
 
-from base_rag_example import BaseRAGExample, create_text_chunks
+from base_rag_example import BaseRAGExample
+from chunking import create_text_chunks
 
 from .email_data.LEANN_email_reader import EmlxReader
 

apps/history_data/history.py

@@ -74,7 +74,7 @@ class ChromeHistoryReader(BaseReader):
                 if count >= max_count and max_count > 0:
                     break
 
-                last_visit, url, title, visit_count, typed_count, hidden = row
+                last_visit, url, title, visit_count, typed_count, _hidden = row
 
                 # Create document content with metadata embedded in text
                 doc_content = f"""

apps/imessage_data/__init__.py

@@ -0,0 +1 @@
+"""iMessage data processing module."""

apps/imessage_data/imessage_reader.py

@@ -0,0 +1,342 @@
+"""
+iMessage data reader.
+
+Reads and processes iMessage conversation data from the macOS Messages database.
+"""
+
+import sqlite3
+from datetime import datetime
+from pathlib import Path
+from typing import Any
+
+from llama_index.core import Document
+from llama_index.core.readers.base import BaseReader
+
+
+class IMessageReader(BaseReader):
+    """
+    iMessage data reader.
+
+    Reads iMessage conversation data from the macOS Messages database (chat.db).
+    Processes conversations into structured documents with metadata.
+    """
+
+    def __init__(self, concatenate_conversations: bool = True) -> None:
+        """
+        Initialize.
+
+        Args:
+            concatenate_conversations: Whether to concatenate messages within conversations for better context
+        """
+        self.concatenate_conversations = concatenate_conversations
+
+    def _get_default_chat_db_path(self) -> Path:
+        """
+        Get the default path to the iMessage chat database.
+
+        Returns:
+            Path to the chat.db file
+        """
+        home = Path.home()
+        return home / "Library" / "Messages" / "chat.db"
+
+    def _convert_cocoa_timestamp(self, cocoa_timestamp: int) -> str:
+        """
+        Convert Cocoa timestamp to readable format.
+
+        Args:
+            cocoa_timestamp: Timestamp in Cocoa format (nanoseconds since 2001-01-01)
+
+        Returns:
+            Formatted timestamp string
+        """
+        if cocoa_timestamp == 0:
+            return "Unknown"
+
+        try:
+            # Cocoa timestamp is nanoseconds since 2001-01-01 00:00:00 UTC
+            # Convert to seconds and add to Unix epoch
+            cocoa_epoch = datetime(2001, 1, 1)
+            unix_timestamp = cocoa_timestamp / 1_000_000_000  # Convert nanoseconds to seconds
+            message_time = cocoa_epoch.timestamp() + unix_timestamp
+            return datetime.fromtimestamp(message_time).strftime("%Y-%m-%d %H:%M:%S")
+        except (ValueError, OSError):
+            return "Unknown"
+
+    def _get_contact_name(self, handle_id: str) -> str:
+        """
+        Get a readable contact name from handle ID.
+
+        Args:
+            handle_id: The handle ID (phone number or email)
+
+        Returns:
+            Formatted contact name
+        """
+        if not handle_id:
+            return "Unknown"
+
+        # Clean up phone numbers and emails for display
+        if "@" in handle_id:
+            return handle_id  # Email address
+        elif handle_id.startswith("+"):
+            return handle_id  # International phone number
+        else:
+            # Try to format as phone number
+            digits = "".join(filter(str.isdigit, handle_id))
+            if len(digits) == 10:
+                return f"({digits[:3]}) {digits[3:6]}-{digits[6:]}"
+            elif len(digits) == 11 and digits[0] == "1":
+                return f"+1 ({digits[1:4]}) {digits[4:7]}-{digits[7:]}"
+            else:
+                return handle_id
+
+    def _read_messages_from_db(self, db_path: Path) -> list[dict]:
+        """
+        Read messages from the iMessage database.
+
+        Args:
+            db_path: Path to the chat.db file
+
+        Returns:
+            List of message dictionaries
+        """
+        if not db_path.exists():
+            print(f"iMessage database not found at: {db_path}")
+            return []
+
+        try:
+            # Connect to the database
+            conn = sqlite3.connect(str(db_path))
+            cursor = conn.cursor()
+
+            # Query to get messages with chat and handle information
+            query = """
+            SELECT
+                m.ROWID as message_id,
+                m.text,
+                m.date,
+                m.is_from_me,
+                m.service,
+                c.chat_identifier,
+                c.display_name as chat_display_name,
+                h.id as handle_id,
+                c.ROWID as chat_id
+            FROM message m
+            LEFT JOIN chat_message_join cmj ON m.ROWID = cmj.message_id
+            LEFT JOIN chat c ON cmj.chat_id = c.ROWID
+            LEFT JOIN handle h ON m.handle_id = h.ROWID
+            WHERE m.text IS NOT NULL AND m.text != ''
+            ORDER BY c.ROWID, m.date
+            """
+
+            cursor.execute(query)
+            rows = cursor.fetchall()
+
+            messages = []
+            for row in rows:
+                (
+                    message_id,
+                    text,
+                    date,
+                    is_from_me,
+                    service,
+                    chat_identifier,
+                    chat_display_name,
+                    handle_id,
+                    chat_id,
+                ) = row
+
+                message = {
+                    "message_id": message_id,
+                    "text": text,
+                    "timestamp": self._convert_cocoa_timestamp(date),
+                    "is_from_me": bool(is_from_me),
+                    "service": service or "iMessage",
+                    "chat_identifier": chat_identifier or "Unknown",
+                    "chat_display_name": chat_display_name or "Unknown Chat",
+                    "handle_id": handle_id or "Unknown",
+                    "contact_name": self._get_contact_name(handle_id or ""),
+                    "chat_id": chat_id,
+                }
+                messages.append(message)
+
+            conn.close()
+            print(f"Found {len(messages)} messages in database")
+            return messages
+
+        except sqlite3.Error as e:
+            print(f"Error reading iMessage database: {e}")
+            return []
+        except Exception as e:
+            print(f"Unexpected error reading iMessage database: {e}")
+            return []
+
+    def _group_messages_by_chat(self, messages: list[dict]) -> dict[int, list[dict]]:
+        """
+        Group messages by chat ID.
+
+        Args:
+            messages: List of message dictionaries
+
+        Returns:
+            Dictionary mapping chat_id to list of messages
+        """
+        chats = {}
+        for message in messages:
+            chat_id = message["chat_id"]
+            if chat_id not in chats:
+                chats[chat_id] = []
+            chats[chat_id].append(message)
+
+        return chats
+
+    def _create_concatenated_content(self, chat_id: int, messages: list[dict]) -> str:
+        """
+        Create concatenated content from chat messages.
+
+        Args:
+            chat_id: The chat ID
+            messages: List of messages in the chat
+
+        Returns:
+            Concatenated text content
+        """
+        if not messages:
+            return ""
+
+        # Get chat info from first message
+        first_msg = messages[0]
+        chat_name = first_msg["chat_display_name"]
+        chat_identifier = first_msg["chat_identifier"]
+
+        # Build message content
+        message_parts = []
+        for message in messages:
+            timestamp = message["timestamp"]
+            is_from_me = message["is_from_me"]
+            text = message["text"]
+            contact_name = message["contact_name"]
+
+            if is_from_me:
+                prefix = "[You]"
+            else:
+                prefix = f"[{contact_name}]"
+
+            if timestamp != "Unknown":
+                prefix += f" ({timestamp})"
+
+            message_parts.append(f"{prefix}: {text}")
+
+        concatenated_text = "\n\n".join(message_parts)
+
+        doc_content = f"""Chat: {chat_name}
+Identifier: {chat_identifier}
+Messages ({len(messages)} messages):
+
+{concatenated_text}
+"""
+        return doc_content
+
+    def _create_individual_content(self, message: dict) -> str:
+        """
+        Create content for individual message.
+
+        Args:
+            message: Message dictionary
+
+        Returns:
+            Formatted message content
+        """
+        timestamp = message["timestamp"]
+        is_from_me = message["is_from_me"]
+        text = message["text"]
+        contact_name = message["contact_name"]
+        chat_name = message["chat_display_name"]
+
+        sender = "You" if is_from_me else contact_name
+
+        return f"""Message from {sender} in chat "{chat_name}"
+Time: {timestamp}
+Content: {text}
+"""
+
+    def load_data(self, input_dir: str | None = None, **load_kwargs: Any) -> list[Document]:
+        """
+        Load iMessage data and return as documents.
+
+        Args:
+            input_dir: Optional path to directory containing chat.db file.
+                      If not provided, uses default macOS location.
+            **load_kwargs: Additional arguments (unused)
+
+        Returns:
+            List of Document objects containing iMessage data
+        """
+        docs = []
+
+        # Determine database path
+        if input_dir:
+            db_path = Path(input_dir) / "chat.db"
+        else:
+            db_path = self._get_default_chat_db_path()
+
+        print(f"Reading iMessage database from: {db_path}")
+
+        # Read messages from database
+        messages = self._read_messages_from_db(db_path)
+        if not messages:
+            return docs
+
+        if self.concatenate_conversations:
+            # Group messages by chat and create concatenated documents
+            chats = self._group_messages_by_chat(messages)
+
+            for chat_id, chat_messages in chats.items():
+                if not chat_messages:
+                    continue
+
+                content = self._create_concatenated_content(chat_id, chat_messages)
+
+                # Create metadata
+                first_msg = chat_messages[0]
+                last_msg = chat_messages[-1]
+
+                metadata = {
+                    "source": "iMessage",
+                    "chat_id": chat_id,
+                    "chat_name": first_msg["chat_display_name"],
+                    "chat_identifier": first_msg["chat_identifier"],
+                    "message_count": len(chat_messages),
+                    "first_message_date": first_msg["timestamp"],
+                    "last_message_date": last_msg["timestamp"],
+                    "participants": list(
+                        {msg["contact_name"] for msg in chat_messages if not msg["is_from_me"]}
+                    ),
+                }
+
+                doc = Document(text=content, metadata=metadata)
+                docs.append(doc)
+
+        else:
+            # Create individual documents for each message
+            for message in messages:
+                content = self._create_individual_content(message)
+
+                metadata = {
+                    "source": "iMessage",
+                    "message_id": message["message_id"],
+                    "chat_id": message["chat_id"],
+                    "chat_name": message["chat_display_name"],
+                    "chat_identifier": message["chat_identifier"],
+                    "timestamp": message["timestamp"],
+                    "is_from_me": message["is_from_me"],
+                    "contact_name": message["contact_name"],
+                    "service": message["service"],
+                }
+
+                doc = Document(text=content, metadata=metadata)
+                docs.append(doc)
+
+        print(f"Created {len(docs)} documents from iMessage data")
+        return docs

apps/imessage_rag.py

@@ -0,0 +1,125 @@
+"""
+iMessage RAG Example.
+
+This example demonstrates how to build a RAG system on your iMessage conversation history.
+"""
+
+import asyncio
+from pathlib import Path
+
+from leann.chunking_utils import create_text_chunks
+
+from apps.base_rag_example import BaseRAGExample
+from apps.imessage_data.imessage_reader import IMessageReader
+
+
+class IMessageRAG(BaseRAGExample):
+    """RAG example for iMessage conversation history."""
+
+    def __init__(self):
+        super().__init__(
+            name="iMessage",
+            description="RAG on your iMessage conversation history",
+            default_index_name="imessage_index",
+        )
+
+    def _add_specific_arguments(self, parser):
+        """Add iMessage-specific arguments."""
+        imessage_group = parser.add_argument_group("iMessage Parameters")
+        imessage_group.add_argument(
+            "--db-path",
+            type=str,
+            default=None,
+            help="Path to iMessage chat.db file (default: ~/Library/Messages/chat.db)",
+        )
+        imessage_group.add_argument(
+            "--concatenate-conversations",
+            action="store_true",
+            default=True,
+            help="Concatenate messages within conversations for better context (default: True)",
+        )
+        imessage_group.add_argument(
+            "--no-concatenate-conversations",
+            action="store_true",
+            help="Process each message individually instead of concatenating by conversation",
+        )
+        imessage_group.add_argument(
+            "--chunk-size",
+            type=int,
+            default=1000,
+            help="Maximum characters per text chunk (default: 1000)",
+        )
+        imessage_group.add_argument(
+            "--chunk-overlap",
+            type=int,
+            default=200,
+            help="Overlap between text chunks (default: 200)",
+        )
+
+    async def load_data(self, args) -> list[str]:
+        """Load iMessage history and convert to text chunks."""
+        print("Loading iMessage conversation history...")
+
+        # Determine concatenation setting
+        concatenate = args.concatenate_conversations and not args.no_concatenate_conversations
+
+        # Initialize iMessage reader
+        reader = IMessageReader(concatenate_conversations=concatenate)
+
+        # Load documents
+        try:
+            if args.db_path:
+                # Use custom database path
+                db_dir = str(Path(args.db_path).parent)
+                documents = reader.load_data(input_dir=db_dir)
+            else:
+                # Use default macOS location
+                documents = reader.load_data()
+
+        except Exception as e:
+            print(f"Error loading iMessage data: {e}")
+            print("\nTroubleshooting tips:")
+            print("1. Make sure you have granted Full Disk Access to your terminal/IDE")
+            print("2. Check that the iMessage database exists at ~/Library/Messages/chat.db")
+            print("3. Try specifying a custom path with --db-path if you have a backup")
+            return []
+
+        if not documents:
+            print("No iMessage conversations found!")
+            return []
+
+        print(f"Loaded {len(documents)} iMessage documents")
+
+        # Show some statistics
+        total_messages = sum(doc.metadata.get("message_count", 1) for doc in documents)
+        print(f"Total messages: {total_messages}")
+
+        if concatenate:
+            # Show chat statistics
+            chat_names = [doc.metadata.get("chat_name", "Unknown") for doc in documents]
+            unique_chats = len(set(chat_names))
+            print(f"Unique conversations: {unique_chats}")
+
+        # Convert to text chunks
+        all_texts = create_text_chunks(
+            documents,
+            chunk_size=args.chunk_size,
+            chunk_overlap=args.chunk_overlap,
+        )
+
+        # Apply max_items limit if specified
+        if args.max_items > 0:
+            all_texts = all_texts[: args.max_items]
+            print(f"Limited to {len(all_texts)} text chunks (max_items={args.max_items})")
+
+        return all_texts
+
+
+async def main():
+    """Main entry point."""
+    app = IMessageRAG()
+    await app.run()
+
+
+if __name__ == "__main__":
+    asyncio.run(main())

apps/slack_data/__init__.py

@@ -0,0 +1 @@
+# Slack MCP data integration for LEANN

apps/slack_data/slack_mcp_reader.py

@@ -0,0 +1,334 @@
+#!/usr/bin/env python3
+"""
+Slack MCP Reader for LEANN
+
+This module provides functionality to connect to Slack MCP servers and fetch message data
+for indexing in LEANN. It supports various Slack MCP server implementations and provides
+flexible message processing options.
+"""
+
+import asyncio
+import json
+import logging
+from typing import Any, Dict, List, Optional
+
+logger = logging.getLogger(__name__)
+
+
+class SlackMCPReader:
+    """
+    Reader for Slack data via MCP (Model Context Protocol) servers.
+
+    This class connects to Slack MCP servers to fetch message data and convert it
+    into a format suitable for LEANN indexing.
+    """
+
+    def __init__(
+        self,
+        mcp_server_command: str,
+        workspace_name: Optional[str] = None,
+        concatenate_conversations: bool = True,
+        max_messages_per_conversation: int = 100,
+    ):
+        """
+        Initialize the Slack MCP Reader.
+
+        Args:
+            mcp_server_command: Command to start the MCP server (e.g., 'slack-mcp-server')
+            workspace_name: Optional workspace name to filter messages
+            concatenate_conversations: Whether to group messages by channel/thread
+            max_messages_per_conversation: Maximum messages to include per conversation
+        """
+        self.mcp_server_command = mcp_server_command
+        self.workspace_name = workspace_name
+        self.concatenate_conversations = concatenate_conversations
+        self.max_messages_per_conversation = max_messages_per_conversation
+        self.mcp_process = None
+
+    async def start_mcp_server(self):
+        """Start the MCP server process."""
+        try:
+            self.mcp_process = await asyncio.create_subprocess_exec(
+                *self.mcp_server_command.split(),
+                stdin=asyncio.subprocess.PIPE,
+                stdout=asyncio.subprocess.PIPE,
+                stderr=asyncio.subprocess.PIPE,
+            )
+            logger.info(f"Started MCP server: {self.mcp_server_command}")
+        except Exception as e:
+            logger.error(f"Failed to start MCP server: {e}")
+            raise
+
+    async def stop_mcp_server(self):
+        """Stop the MCP server process."""
+        if self.mcp_process:
+            self.mcp_process.terminate()
+            await self.mcp_process.wait()
+            logger.info("Stopped MCP server")
+
+    async def send_mcp_request(self, request: Dict[str, Any]) -> Dict[str, Any]:
+        """Send a request to the MCP server and get response."""
+        if not self.mcp_process:
+            raise RuntimeError("MCP server not started")
+
+        request_json = json.dumps(request) + "\n"
+        self.mcp_process.stdin.write(request_json.encode())
+        await self.mcp_process.stdin.drain()
+
+        response_line = await self.mcp_process.stdout.readline()
+        if not response_line:
+            raise RuntimeError("No response from MCP server")
+
+        return json.loads(response_line.decode().strip())
+
+    async def initialize_mcp_connection(self):
+        """Initialize the MCP connection."""
+        init_request = {
+            "jsonrpc": "2.0",
+            "id": 1,
+            "method": "initialize",
+            "params": {
+                "protocolVersion": "2024-11-05",
+                "capabilities": {},
+                "clientInfo": {"name": "leann-slack-reader", "version": "1.0.0"},
+            },
+        }
+
+        response = await self.send_mcp_request(init_request)
+        if "error" in response:
+            raise RuntimeError(f"MCP initialization failed: {response['error']}")
+
+        logger.info("MCP connection initialized successfully")
+
+    async def list_available_tools(self) -> List[Dict[str, Any]]:
+        """List available tools from the MCP server."""
+        list_request = {"jsonrpc": "2.0", "id": 2, "method": "tools/list", "params": {}}
+
+        response = await self.send_mcp_request(list_request)
+        if "error" in response:
+            raise RuntimeError(f"Failed to list tools: {response['error']}")
+
+        return response.get("result", {}).get("tools", [])
+
+    async def fetch_slack_messages(
+        self, channel: Optional[str] = None, limit: int = 100
+    ) -> List[Dict[str, Any]]:
+        """
+        Fetch Slack messages using MCP tools.
+
+        Args:
+            channel: Optional channel name to filter messages
+            limit: Maximum number of messages to fetch
+
+        Returns:
+            List of message dictionaries
+        """
+        # This is a generic implementation - specific MCP servers may have different tool names
+        # Common tool names might be: 'get_messages', 'list_messages', 'fetch_channel_history'
+
+        tools = await self.list_available_tools()
+        message_tool = None
+
+        # Look for a tool that can fetch messages
+        for tool in tools:
+            tool_name = tool.get("name", "").lower()
+            if any(
+                keyword in tool_name
+                for keyword in ["message", "history", "channel", "conversation"]
+            ):
+                message_tool = tool
+                break
+
+        if not message_tool:
+            raise RuntimeError("No message fetching tool found in MCP server")
+
+        # Prepare tool call parameters
+        tool_params = {"limit": limit}
+        if channel:
+            # Try common parameter names for channel specification
+            for param_name in ["channel", "channel_id", "channel_name"]:
+                tool_params[param_name] = channel
+                break
+
+        fetch_request = {
+            "jsonrpc": "2.0",
+            "id": 3,
+            "method": "tools/call",
+            "params": {"name": message_tool["name"], "arguments": tool_params},
+        }
+
+        response = await self.send_mcp_request(fetch_request)
+        if "error" in response:
+            raise RuntimeError(f"Failed to fetch messages: {response['error']}")
+
+        # Extract messages from response - format may vary by MCP server
+        result = response.get("result", {})
+        if "content" in result and isinstance(result["content"], list):
+            # Some MCP servers return content as a list
+            content = result["content"][0] if result["content"] else {}
+            if "text" in content:
+                try:
+                    messages = json.loads(content["text"])
+                except json.JSONDecodeError:
+                    # If not JSON, treat as plain text
+                    messages = [{"text": content["text"], "channel": channel or "unknown"}]
+            else:
+                messages = result["content"]
+        else:
+            # Direct message format
+            messages = result.get("messages", [result])
+
+        return messages if isinstance(messages, list) else [messages]
+
+    def _format_message(self, message: Dict[str, Any]) -> str:
+        """Format a single message for indexing."""
+        text = message.get("text", "")
+        user = message.get("user", message.get("username", "Unknown"))
+        channel = message.get("channel", message.get("channel_name", "Unknown"))
+        timestamp = message.get("ts", message.get("timestamp", ""))
+
+        # Format timestamp if available
+        formatted_time = ""
+        if timestamp:
+            try:
+                import datetime
+
+                if isinstance(timestamp, str) and "." in timestamp:
+                    dt = datetime.datetime.fromtimestamp(float(timestamp))
+                    formatted_time = dt.strftime("%Y-%m-%d %H:%M:%S")
+                elif isinstance(timestamp, (int, float)):
+                    dt = datetime.datetime.fromtimestamp(timestamp)
+                    formatted_time = dt.strftime("%Y-%m-%d %H:%M:%S")
+                else:
+                    formatted_time = str(timestamp)
+            except (ValueError, TypeError):
+                formatted_time = str(timestamp)
+
+        # Build formatted message
+        parts = []
+        if channel:
+            parts.append(f"Channel: #{channel}")
+        if user:
+            parts.append(f"User: {user}")
+        if formatted_time:
+            parts.append(f"Time: {formatted_time}")
+        if text:
+            parts.append(f"Message: {text}")
+
+        return "\n".join(parts)
+
+    def _create_concatenated_content(self, messages: List[Dict[str, Any]], channel: str) -> str:
+        """Create concatenated content from multiple messages in a channel."""
+        if not messages:
+            return ""
+
+        # Sort messages by timestamp if available
+        try:
+            messages.sort(key=lambda x: float(x.get("ts", x.get("timestamp", 0))))
+        except (ValueError, TypeError):
+            pass  # Keep original order if timestamps aren't numeric
+
+        # Limit messages per conversation
+        if len(messages) > self.max_messages_per_conversation:
+            messages = messages[-self.max_messages_per_conversation :]
+
+        # Create header
+        content_parts = [
+            f"Slack Channel: #{channel}",
+            f"Message Count: {len(messages)}",
+            f"Workspace: {self.workspace_name or 'Unknown'}",
+            "=" * 50,
+            "",
+        ]
+
+        # Add messages
+        for message in messages:
+            formatted_msg = self._format_message(message)
+            if formatted_msg.strip():
+                content_parts.append(formatted_msg)
+                content_parts.append("-" * 30)
+                content_parts.append("")
+
+        return "\n".join(content_parts)
+
+    async def read_slack_data(self, channels: Optional[List[str]] = None) -> List[str]:
+        """
+        Read Slack data and return formatted text chunks.
+
+        Args:
+            channels: Optional list of channel names to fetch. If None, fetches from all available channels.
+
+        Returns:
+            List of formatted text chunks ready for LEANN indexing
+        """
+        try:
+            await self.start_mcp_server()
+            await self.initialize_mcp_connection()
+
+            all_texts = []
+
+            if channels:
+                # Fetch specific channels
+                for channel in channels:
+                    try:
+                        messages = await self.fetch_slack_messages(channel=channel, limit=1000)
+                        if messages:
+                            if self.concatenate_conversations:
+                                text_content = self._create_concatenated_content(messages, channel)
+                                if text_content.strip():
+                                    all_texts.append(text_content)
+                            else:
+                                # Process individual messages
+                                for message in messages:
+                                    formatted_msg = self._format_message(message)
+                                    if formatted_msg.strip():
+                                        all_texts.append(formatted_msg)
+                    except Exception as e:
+                        logger.warning(f"Failed to fetch messages from channel {channel}: {e}")
+                        continue
+            else:
+                # Fetch from all available channels/conversations
+                # This is a simplified approach - real implementation would need to
+                # discover available channels first
+                try:
+                    messages = await self.fetch_slack_messages(limit=1000)
+                    if messages:
+                        # Group messages by channel if concatenating
+                        if self.concatenate_conversations:
+                            channel_messages = {}
+                            for message in messages:
+                                channel = message.get(
+                                    "channel", message.get("channel_name", "general")
+                                )
+                                if channel not in channel_messages:
+                                    channel_messages[channel] = []
+                                channel_messages[channel].append(message)
+
+                            # Create concatenated content for each channel
+                            for channel, msgs in channel_messages.items():
+                                text_content = self._create_concatenated_content(msgs, channel)
+                                if text_content.strip():
+                                    all_texts.append(text_content)
+                        else:
+                            # Process individual messages
+                            for message in messages:
+                                formatted_msg = self._format_message(message)
+                                if formatted_msg.strip():
+                                    all_texts.append(formatted_msg)
+                except Exception as e:
+                    logger.error(f"Failed to fetch messages: {e}")
+
+            return all_texts
+
+        finally:
+            await self.stop_mcp_server()
+
+    async def __aenter__(self):
+        """Async context manager entry."""
+        await self.start_mcp_server()
+        await self.initialize_mcp_connection()
+        return self
+
+    async def __aexit__(self, exc_type, exc_val, exc_tb):
+        """Async context manager exit."""
+        await self.stop_mcp_server()

apps/slack_rag.py

@@ -0,0 +1,204 @@
+#!/usr/bin/env python3
+"""
+Slack RAG Application with MCP Support
+
+This application enables RAG (Retrieval-Augmented Generation) on Slack messages
+by connecting to Slack MCP servers to fetch live data and index it in LEANN.
+
+Usage:
+    python -m apps.slack_rag --mcp-server "slack-mcp-server" --query "What did the team discuss about the project?"
+"""
+
+import argparse
+import asyncio
+from typing import List
+
+from apps.base_rag_example import BaseRAGExample
+from apps.slack_data.slack_mcp_reader import SlackMCPReader
+
+
+class SlackMCPRAG(BaseRAGExample):
+    """
+    RAG application for Slack messages via MCP servers.
+
+    This class provides a complete RAG pipeline for Slack data, including
+    MCP server connection, data fetching, indexing, and interactive chat.
+    """
+
+    def __init__(self):
+        super().__init__()
+        self.default_index_name = "slack_messages"
+
+    def _add_specific_arguments(self, parser: argparse.ArgumentParser):
+        """Add Slack MCP-specific arguments."""
+        parser.add_argument(
+            "--mcp-server",
+            type=str,
+            required=True,
+            help="Command to start the Slack MCP server (e.g., 'slack-mcp-server' or 'npx slack-mcp-server')",
+        )
+
+        parser.add_argument(
+            "--workspace-name",
+            type=str,
+            help="Slack workspace name for better organization and filtering",
+        )
+
+        parser.add_argument(
+            "--channels",
+            nargs="+",
+            help="Specific Slack channels to index (e.g., general random). If not specified, fetches from all available channels",
+        )
+
+        parser.add_argument(
+            "--concatenate-conversations",
+            action="store_true",
+            default=True,
+            help="Group messages by channel/thread for better context (default: True)",
+        )
+
+        parser.add_argument(
+            "--no-concatenate-conversations",
+            action="store_true",
+            help="Process individual messages instead of grouping by channel",
+        )
+
+        parser.add_argument(
+            "--max-messages-per-channel",
+            type=int,
+            default=100,
+            help="Maximum number of messages to include per channel (default: 100)",
+        )
+
+        parser.add_argument(
+            "--test-connection",
+            action="store_true",
+            help="Test MCP server connection and list available tools without indexing",
+        )
+
+    async def test_mcp_connection(self, args) -> bool:
+        """Test the MCP server connection and display available tools."""
+        print(f"Testing connection to MCP server: {args.mcp_server}")
+
+        try:
+            reader = SlackMCPReader(
+                mcp_server_command=args.mcp_server,
+                workspace_name=args.workspace_name,
+                concatenate_conversations=not args.no_concatenate_conversations,
+                max_messages_per_conversation=args.max_messages_per_channel,
+            )
+
+            async with reader:
+                tools = await reader.list_available_tools()
+
+                print("\n✅ Successfully connected to MCP server!")
+                print(f"Available tools ({len(tools)}):")
+
+                for i, tool in enumerate(tools, 1):
+                    name = tool.get("name", "Unknown")
+                    description = tool.get("description", "No description available")
+                    print(f"\n{i}. {name}")
+                    print(
+                        f"   Description: {description[:100]}{'...' if len(description) > 100 else ''}"
+                    )
+
+                    # Show input schema if available
+                    schema = tool.get("inputSchema", {})
+                    if schema.get("properties"):
+                        props = list(schema["properties"].keys())[:3]  # Show first 3 properties
+                        print(
+                            f"   Parameters: {', '.join(props)}{'...' if len(schema['properties']) > 3 else ''}"
+                        )
+
+                return True
+
+        except Exception as e:
+            print(f"\n❌ Failed to connect to MCP server: {e}")
+            print("\nTroubleshooting tips:")
+            print("1. Make sure the MCP server is installed and accessible")
+            print("2. Check if the server command is correct")
+            print("3. Ensure you have proper authentication/credentials configured")
+            print("4. Try running the MCP server command directly to test it")
+            return False
+
+    async def load_data(self, args) -> List[str]:
+        """Load Slack messages via MCP server."""
+        print(f"Connecting to Slack MCP server: {args.mcp_server}")
+
+        if args.workspace_name:
+            print(f"Workspace: {args.workspace_name}")
+
+        if args.channels:
+            print(f"Channels: {', '.join(args.channels)}")
+        else:
+            print("Fetching from all available channels")
+
+        concatenate = not args.no_concatenate_conversations
+        print(
+            f"Processing mode: {'Concatenated conversations' if concatenate else 'Individual messages'}"
+        )
+
+        try:
+            reader = SlackMCPReader(
+                mcp_server_command=args.mcp_server,
+                workspace_name=args.workspace_name,
+                concatenate_conversations=concatenate,
+                max_messages_per_conversation=args.max_messages_per_channel,
+            )
+
+            texts = await reader.read_slack_data(channels=args.channels)
+
+            if not texts:
+                print("❌ No messages found! This could mean:")
+                print("- The MCP server couldn't fetch messages")
+                print("- The specified channels don't exist or are empty")
+                print("- Authentication issues with the Slack workspace")
+                return []
+
+            print(f"✅ Successfully loaded {len(texts)} text chunks from Slack")
+
+            # Show sample of what was loaded
+            if texts:
+                sample_text = texts[0][:200] + "..." if len(texts[0]) > 200 else texts[0]
+                print("\nSample content:")
+                print("-" * 40)
+                print(sample_text)
+                print("-" * 40)
+
+            return texts
+
+        except Exception as e:
+            print(f"❌ Error loading Slack data: {e}")
+            print("\nThis might be due to:")
+            print("- MCP server connection issues")
+            print("- Authentication problems")
+            print("- Network connectivity issues")
+            print("- Incorrect channel names")
+            raise
+
+    async def run(self):
+        """Main entry point with MCP connection testing."""
+        args = self.parser.parse_args()
+
+        # Test connection if requested
+        if args.test_connection:
+            success = await self.test_mcp_connection(args)
+            if not success:
+                return
+            print(
+                "\n🎉 MCP server is working! You can now run without --test-connection to start indexing."
+            )
+            return
+
+        # Run the standard RAG pipeline
+        await super().run()
+
+
+async def main():
+    """Main entry point for the Slack MCP RAG application."""
+    app = SlackMCPRAG()
+    await app.run()
+
+
+if __name__ == "__main__":
+    asyncio.run(main())

apps/twitter_data/__init__.py

@@ -0,0 +1 @@
+# Twitter MCP data integration for LEANN

apps/twitter_data/twitter_mcp_reader.py

@@ -0,0 +1,295 @@
+#!/usr/bin/env python3
+"""
+Twitter MCP Reader for LEANN
+
+This module provides functionality to connect to Twitter MCP servers and fetch bookmark data
+for indexing in LEANN. It supports various Twitter MCP server implementations and provides
+flexible bookmark processing options.
+"""
+
+import asyncio
+import json
+import logging
+from typing import Any, Dict, List, Optional
+
+logger = logging.getLogger(__name__)
+
+
+class TwitterMCPReader:
+    """
+    Reader for Twitter bookmark data via MCP (Model Context Protocol) servers.
+
+    This class connects to Twitter MCP servers to fetch bookmark data and convert it
+    into a format suitable for LEANN indexing.
+    """
+
+    def __init__(
+        self,
+        mcp_server_command: str,
+        username: Optional[str] = None,
+        include_tweet_content: bool = True,
+        include_metadata: bool = True,
+        max_bookmarks: int = 1000,
+    ):
+        """
+        Initialize the Twitter MCP Reader.
+
+        Args:
+            mcp_server_command: Command to start the MCP server (e.g., 'twitter-mcp-server')
+            username: Optional Twitter username to filter bookmarks
+            include_tweet_content: Whether to include full tweet content
+            include_metadata: Whether to include tweet metadata (likes, retweets, etc.)
+            max_bookmarks: Maximum number of bookmarks to fetch
+        """
+        self.mcp_server_command = mcp_server_command
+        self.username = username
+        self.include_tweet_content = include_tweet_content
+        self.include_metadata = include_metadata
+        self.max_bookmarks = max_bookmarks
+        self.mcp_process = None
+
+    async def start_mcp_server(self):
+        """Start the MCP server process."""
+        try:
+            self.mcp_process = await asyncio.create_subprocess_exec(
+                *self.mcp_server_command.split(),
+                stdin=asyncio.subprocess.PIPE,
+                stdout=asyncio.subprocess.PIPE,
+                stderr=asyncio.subprocess.PIPE,
+            )
+            logger.info(f"Started MCP server: {self.mcp_server_command}")
+        except Exception as e:
+            logger.error(f"Failed to start MCP server: {e}")
+            raise
+
+    async def stop_mcp_server(self):
+        """Stop the MCP server process."""
+        if self.mcp_process:
+            self.mcp_process.terminate()
+            await self.mcp_process.wait()
+            logger.info("Stopped MCP server")
+
+    async def send_mcp_request(self, request: Dict[str, Any]) -> Dict[str, Any]:
+        """Send a request to the MCP server and get response."""
+        if not self.mcp_process:
+            raise RuntimeError("MCP server not started")
+
+        request_json = json.dumps(request) + "\n"
+        self.mcp_process.stdin.write(request_json.encode())
+        await self.mcp_process.stdin.drain()
+
+        response_line = await self.mcp_process.stdout.readline()
+        if not response_line:
+            raise RuntimeError("No response from MCP server")
+
+        return json.loads(response_line.decode().strip())
+
+    async def initialize_mcp_connection(self):
+        """Initialize the MCP connection."""
+        init_request = {
+            "jsonrpc": "2.0",
+            "id": 1,
+            "method": "initialize",
+            "params": {
+                "protocolVersion": "2024-11-05",
+                "capabilities": {},
+                "clientInfo": {"name": "leann-twitter-reader", "version": "1.0.0"},
+            },
+        }
+
+        response = await self.send_mcp_request(init_request)
+        if "error" in response:
+            raise RuntimeError(f"MCP initialization failed: {response['error']}")
+
+        logger.info("MCP connection initialized successfully")
+
+    async def list_available_tools(self) -> List[Dict[str, Any]]:
+        """List available tools from the MCP server."""
+        list_request = {"jsonrpc": "2.0", "id": 2, "method": "tools/list", "params": {}}
+
+        response = await self.send_mcp_request(list_request)
+        if "error" in response:
+            raise RuntimeError(f"Failed to list tools: {response['error']}")
+
+        return response.get("result", {}).get("tools", [])
+
+    async def fetch_twitter_bookmarks(self, limit: Optional[int] = None) -> List[Dict[str, Any]]:
+        """
+        Fetch Twitter bookmarks using MCP tools.
+
+        Args:
+            limit: Maximum number of bookmarks to fetch
+
+        Returns:
+            List of bookmark dictionaries
+        """
+        tools = await self.list_available_tools()
+        bookmark_tool = None
+
+        # Look for a tool that can fetch bookmarks
+        for tool in tools:
+            tool_name = tool.get("name", "").lower()
+            if any(keyword in tool_name for keyword in ["bookmark", "saved", "favorite"]):
+                bookmark_tool = tool
+                break
+
+        if not bookmark_tool:
+            raise RuntimeError("No bookmark fetching tool found in MCP server")
+
+        # Prepare tool call parameters
+        tool_params = {}
+        if limit or self.max_bookmarks:
+            tool_params["limit"] = limit or self.max_bookmarks
+        if self.username:
+            tool_params["username"] = self.username
+
+        fetch_request = {
+            "jsonrpc": "2.0",
+            "id": 3,
+            "method": "tools/call",
+            "params": {"name": bookmark_tool["name"], "arguments": tool_params},
+        }
+
+        response = await self.send_mcp_request(fetch_request)
+        if "error" in response:
+            raise RuntimeError(f"Failed to fetch bookmarks: {response['error']}")
+
+        # Extract bookmarks from response
+        result = response.get("result", {})
+        if "content" in result and isinstance(result["content"], list):
+            content = result["content"][0] if result["content"] else {}
+            if "text" in content:
+                try:
+                    bookmarks = json.loads(content["text"])
+                except json.JSONDecodeError:
+                    # If not JSON, treat as plain text
+                    bookmarks = [{"text": content["text"], "source": "twitter"}]
+            else:
+                bookmarks = result["content"]
+        else:
+            bookmarks = result.get("bookmarks", result.get("tweets", [result]))
+
+        return bookmarks if isinstance(bookmarks, list) else [bookmarks]
+
+    def _format_bookmark(self, bookmark: Dict[str, Any]) -> str:
+        """Format a single bookmark for indexing."""
+        # Extract tweet information
+        text = bookmark.get("text", bookmark.get("content", ""))
+        author = bookmark.get(
+            "author", bookmark.get("username", bookmark.get("user", {}).get("username", "Unknown"))
+        )
+        timestamp = bookmark.get("created_at", bookmark.get("timestamp", ""))
+        url = bookmark.get("url", bookmark.get("tweet_url", ""))
+
+        # Extract metadata if available
+        likes = bookmark.get("likes", bookmark.get("favorite_count", 0))
+        retweets = bookmark.get("retweets", bookmark.get("retweet_count", 0))
+        replies = bookmark.get("replies", bookmark.get("reply_count", 0))
+
+        # Build formatted bookmark
+        parts = []
+
+        # Header
+        parts.append("=== Twitter Bookmark ===")
+
+        if author:
+            parts.append(f"Author: @{author}")
+
+        if timestamp:
+            # Format timestamp if it's a standard format
+            try:
+                import datetime
+
+                if "T" in str(timestamp):  # ISO format
+                    dt = datetime.datetime.fromisoformat(timestamp.replace("Z", "+00:00"))
+                    formatted_time = dt.strftime("%Y-%m-%d %H:%M:%S")
+                else:
+                    formatted_time = str(timestamp)
+                parts.append(f"Date: {formatted_time}")
+            except (ValueError, TypeError):
+                parts.append(f"Date: {timestamp}")
+
+        if url:
+            parts.append(f"URL: {url}")
+
+        # Tweet content
+        if text and self.include_tweet_content:
+            parts.append("")
+            parts.append("Content:")
+            parts.append(text)
+
+        # Metadata
+        if self.include_metadata and any([likes, retweets, replies]):
+            parts.append("")
+            parts.append("Engagement:")
+            if likes:
+                parts.append(f"  Likes: {likes}")
+            if retweets:
+                parts.append(f"  Retweets: {retweets}")
+            if replies:
+                parts.append(f"  Replies: {replies}")
+
+        # Extract hashtags and mentions if available
+        hashtags = bookmark.get("hashtags", [])
+        mentions = bookmark.get("mentions", [])
+
+        if hashtags or mentions:
+            parts.append("")
+            if hashtags:
+                parts.append(f"Hashtags: {', '.join(hashtags)}")
+            if mentions:
+                parts.append(f"Mentions: {', '.join(mentions)}")
+
+        return "\n".join(parts)
+
+    async def read_twitter_bookmarks(self) -> List[str]:
+        """
+        Read Twitter bookmark data and return formatted text chunks.
+
+        Returns:
+            List of formatted text chunks ready for LEANN indexing
+        """
+        try:
+            await self.start_mcp_server()
+            await self.initialize_mcp_connection()
+
+            print(f"Fetching up to {self.max_bookmarks} bookmarks...")
+            if self.username:
+                print(f"Filtering for user: @{self.username}")
+
+            bookmarks = await self.fetch_twitter_bookmarks()
+
+            if not bookmarks:
+                print("No bookmarks found")
+                return []
+
+            print(f"Processing {len(bookmarks)} bookmarks...")
+
+            all_texts = []
+            processed_count = 0
+
+            for bookmark in bookmarks:
+                try:
+                    formatted_bookmark = self._format_bookmark(bookmark)
+                    if formatted_bookmark.strip():
+                        all_texts.append(formatted_bookmark)
+                        processed_count += 1
+                except Exception as e:
+                    logger.warning(f"Failed to format bookmark: {e}")
+                    continue
+
+            print(f"Successfully processed {processed_count} bookmarks")
+            return all_texts
+
+        finally:
+            await self.stop_mcp_server()
+
+    async def __aenter__(self):
+        """Async context manager entry."""
+        await self.start_mcp_server()
+        await self.initialize_mcp_connection()
+        return self
+
+    async def __aexit__(self, exc_type, exc_val, exc_tb):
+        """Async context manager exit."""
+        await self.stop_mcp_server()

apps/twitter_rag.py

@@ -0,0 +1,190 @@
+#!/usr/bin/env python3
+"""
+Twitter RAG Application with MCP Support
+
+This application enables RAG (Retrieval-Augmented Generation) on Twitter bookmarks
+by connecting to Twitter MCP servers to fetch live data and index it in LEANN.
+
+Usage:
+    python -m apps.twitter_rag --mcp-server "twitter-mcp-server" --query "What articles did I bookmark about AI?"
+"""
+
+import argparse
+import asyncio
+from pathlib import Path
+from typing import List
+
+from apps.base_rag_example import BaseRAGExample
+from apps.twitter_data.twitter_mcp_reader import TwitterMCPReader
+
+
+class TwitterMCPRAG(BaseRAGExample):
+    """
+    RAG application for Twitter bookmarks via MCP servers.
+    
+    This class provides a complete RAG pipeline for Twitter bookmark data, including
+    MCP server connection, data fetching, indexing, and interactive chat.
+    """
+    
+    def __init__(self):
+        super().__init__()
+        self.default_index_name = "twitter_bookmarks"
+        
+    def _add_specific_arguments(self, parser: argparse.ArgumentParser):
+        """Add Twitter MCP-specific arguments."""
+        parser.add_argument(
+            "--mcp-server",
+            type=str,
+            required=True,
+            help="Command to start the Twitter MCP server (e.g., 'twitter-mcp-server' or 'npx twitter-mcp-server')"
+        )
+        
+        parser.add_argument(
+            "--username",
+            type=str,
+            help="Twitter username to filter bookmarks (without @)"
+        )
+        
+        parser.add_argument(
+            "--max-bookmarks",
+            type=int,
+            default=1000,
+            help="Maximum number of bookmarks to fetch (default: 1000)"
+        )
+        
+        parser.add_argument(
+            "--no-tweet-content",
+            action="store_true",
+            help="Exclude tweet content, only include metadata"
+        )
+        
+        parser.add_argument(
+            "--no-metadata",
+            action="store_true",
+            help="Exclude engagement metadata (likes, retweets, etc.)"
+        )
+        
+        parser.add_argument(
+            "--test-connection",
+            action="store_true",
+            help="Test MCP server connection and list available tools without indexing"
+        )
+        
+    async def test_mcp_connection(self, args) -> bool:
+        """Test the MCP server connection and display available tools."""
+        print(f"Testing connection to MCP server: {args.mcp_server}")
+        
+        try:
+            reader = TwitterMCPReader(
+                mcp_server_command=args.mcp_server,
+                username=args.username,
+                include_tweet_content=not args.no_tweet_content,
+                include_metadata=not args.no_metadata,
+                max_bookmarks=args.max_bookmarks,
+            )
+            
+            async with reader:
+                tools = await reader.list_available_tools()
+                
+                print(f"\n✅ Successfully connected to MCP server!")
+                print(f"Available tools ({len(tools)}):")
+                
+                for i, tool in enumerate(tools, 1):
+                    name = tool.get("name", "Unknown")
+                    description = tool.get("description", "No description available")
+                    print(f"\n{i}. {name}")
+                    print(f"   Description: {description[:100]}{'...' if len(description) > 100 else ''}")
+                    
+                    # Show input schema if available
+                    schema = tool.get("inputSchema", {})
+                    if schema.get("properties"):
+                        props = list(schema["properties"].keys())[:3]  # Show first 3 properties
+                        print(f"   Parameters: {', '.join(props)}{'...' if len(schema['properties']) > 3 else ''}")
+                
+                return True
+                
+        except Exception as e:
+            print(f"\n❌ Failed to connect to MCP server: {e}")
+            print("\nTroubleshooting tips:")
+            print("1. Make sure the Twitter MCP server is installed and accessible")
+            print("2. Check if the server command is correct")
+            print("3. Ensure you have proper Twitter API credentials configured")
+            print("4. Verify your Twitter account has bookmarks to fetch")
+            print("5. Try running the MCP server command directly to test it")
+            return False
+            
+    async def load_data(self, args) -> List[str]:
+        """Load Twitter bookmarks via MCP server."""
+        print(f"Connecting to Twitter MCP server: {args.mcp_server}")
+        
+        if args.username:
+            print(f"Username filter: @{args.username}")
+            
+        print(f"Max bookmarks: {args.max_bookmarks}")
+        print(f"Include tweet content: {not args.no_tweet_content}")
+        print(f"Include metadata: {not args.no_metadata}")
+        
+        try:
+            reader = TwitterMCPReader(
+                mcp_server_command=args.mcp_server,
+                username=args.username,
+                include_tweet_content=not args.no_tweet_content,
+                include_metadata=not args.no_metadata,
+                max_bookmarks=args.max_bookmarks,
+            )
+            
+            texts = await reader.read_twitter_bookmarks()
+            
+            if not texts:
+                print("❌ No bookmarks found! This could mean:")
+                print("- You don't have any bookmarks on Twitter")
+                print("- The MCP server couldn't access your bookmarks")
+                print("- Authentication issues with Twitter API")
+                print("- The username filter didn't match any bookmarks")
+                return []
+                
+            print(f"✅ Successfully loaded {len(texts)} bookmarks from Twitter")
+            
+            # Show sample of what was loaded
+            if texts:
+                sample_text = texts[0][:300] + "..." if len(texts[0]) > 300 else texts[0]
+                print(f"\nSample bookmark:")
+                print("-" * 50)
+                print(sample_text)
+                print("-" * 50)
+                
+            return texts
+            
+        except Exception as e:
+            print(f"❌ Error loading Twitter bookmarks: {e}")
+            print("\nThis might be due to:")
+            print("- MCP server connection issues")
+            print("- Twitter API authentication problems")
+            print("- Network connectivity issues")
+            print("- Rate limiting from Twitter API")
+            raise
+            
+    async def run(self):
+        """Main entry point with MCP connection testing."""
+        args = self.parser.parse_args()
+        
+        # Test connection if requested
+        if args.test_connection:
+            success = await self.test_mcp_connection(args)
+            if not success:
+                return
+            print(f"\n🎉 MCP server is working! You can now run without --test-connection to start indexing.")
+            return
+            
+        # Run the standard RAG pipeline
+        await super().run()
+
+
+async def main():
+    """Main entry point for the Twitter MCP RAG application."""
+    app = TwitterMCPRAG()
+    await app.run()
+
+
+if __name__ == "__main__":
+    asyncio.run(main())

benchmarks/README.md

@@ -1,9 +1,24 @@
-# 🧪 Leann Sanity Checks
+# 🧪 LEANN Benchmarks & Testing
 
-This directory contains comprehensive sanity checks for the Leann system, ensuring all components work correctly across different configurations.
+This directory contains performance benchmarks and comprehensive tests for the LEANN system, including backend comparisons and sanity checks across different configurations.
 
 ## 📁 Test Files
 
+### `diskann_vs_hnsw_speed_comparison.py`
+Performance comparison between DiskANN and HNSW backends:
+- ✅ **Search latency** comparison with both backends using recompute
+- ✅ **Index size** and **build time** measurements
+- ✅ **Score validity** testing (ensures no -inf scores)
+- ✅ **Configurable dataset sizes** for different scales
+
+```bash
+# Quick comparison with 500 docs, 10 queries
+python benchmarks/diskann_vs_hnsw_speed_comparison.py
+
+# Large-scale comparison with 2000 docs, 20 queries
+python benchmarks/diskann_vs_hnsw_speed_comparison.py 2000 20
+```
+
 ### `test_distance_functions.py`
 Tests all supported distance functions across DiskANN backend:
 - ✅ **MIPS** (Maximum Inner Product Search)

benchmarks/benchmark_no_recompute.py

@@ -0,0 +1,148 @@
+import argparse
+import os
+import time
+from pathlib import Path
+
+from leann import LeannBuilder, LeannSearcher
+
+
+def _meta_exists(index_path: str) -> bool:
+    p = Path(index_path)
+    return (p.parent / f"{p.stem}.meta.json").exists()
+
+
+def ensure_index(index_path: str, backend_name: str, num_docs: int, is_recompute: bool) -> None:
+    # if _meta_exists(index_path):
+    #     return
+    kwargs = {}
+    if backend_name == "hnsw":
+        kwargs["is_compact"] = is_recompute
+    builder = LeannBuilder(
+        backend_name=backend_name,
+        embedding_model=os.getenv("LEANN_EMBED_MODEL", "facebook/contriever"),
+        embedding_mode=os.getenv("LEANN_EMBED_MODE", "sentence-transformers"),
+        graph_degree=32,
+        complexity=64,
+        is_recompute=is_recompute,
+        num_threads=4,
+        **kwargs,
+    )
+    for i in range(num_docs):
+        builder.add_text(
+            f"This is a test document number {i}. It contains some repeated text for benchmarking."
+        )
+    builder.build_index(index_path)
+
+
+def _bench_group(
+    index_path: str,
+    recompute: bool,
+    query: str,
+    repeats: int,
+    complexity: int = 32,
+    top_k: int = 10,
+) -> float:
+    # Independent searcher per group; fixed port when recompute
+    searcher = LeannSearcher(index_path=index_path)
+
+    # Warm-up once
+    _ = searcher.search(
+        query,
+        top_k=top_k,
+        complexity=complexity,
+        recompute_embeddings=recompute,
+    )
+
+    def _once() -> float:
+        t0 = time.time()
+        _ = searcher.search(
+            query,
+            top_k=top_k,
+            complexity=complexity,
+            recompute_embeddings=recompute,
+        )
+        return time.time() - t0
+
+    if repeats <= 1:
+        t = _once()
+    else:
+        vals = [_once() for _ in range(repeats)]
+        vals.sort()
+        t = vals[len(vals) // 2]
+
+    searcher.cleanup()
+    return t
+
+
+def main():
+    parser = argparse.ArgumentParser()
+    parser.add_argument("--num-docs", type=int, default=5000)
+    parser.add_argument("--repeats", type=int, default=3)
+    parser.add_argument("--complexity", type=int, default=32)
+    args = parser.parse_args()
+
+    base = Path.cwd() / ".leann" / "indexes" / f"bench_n{args.num_docs}"
+    base.parent.mkdir(parents=True, exist_ok=True)
+    # ---------- Build HNSW variants ----------
+    hnsw_r = str(base / f"hnsw_recompute_n{args.num_docs}.leann")
+    hnsw_nr = str(base / f"hnsw_norecompute_n{args.num_docs}.leann")
+    ensure_index(hnsw_r, "hnsw", args.num_docs, True)
+    ensure_index(hnsw_nr, "hnsw", args.num_docs, False)
+
+    # ---------- Build DiskANN variants ----------
+    diskann_r = str(base / "diskann_r.leann")
+    diskann_nr = str(base / "diskann_nr.leann")
+    ensure_index(diskann_r, "diskann", args.num_docs, True)
+    ensure_index(diskann_nr, "diskann", args.num_docs, False)
+
+    # ---------- Helpers ----------
+    def _size_for(prefix: str) -> int:
+        p = Path(prefix)
+        base_dir = p.parent
+        stem = p.stem
+        total = 0
+        for f in base_dir.iterdir():
+            if f.is_file() and f.name.startswith(stem):
+                total += f.stat().st_size
+        return total
+
+    # ---------- HNSW benchmark ----------
+    t_hnsw_r = _bench_group(
+        hnsw_r, True, "test document number 42", repeats=args.repeats, complexity=args.complexity
+    )
+    t_hnsw_nr = _bench_group(
+        hnsw_nr, False, "test document number 42", repeats=args.repeats, complexity=args.complexity
+    )
+    size_hnsw_r = _size_for(hnsw_r)
+    size_hnsw_nr = _size_for(hnsw_nr)
+
+    print("Benchmark results (HNSW):")
+    print(f"  recompute=True:  search_time={t_hnsw_r:.3f}s, size={size_hnsw_r / 1024 / 1024:.1f}MB")
+    print(
+        f"  recompute=False: search_time={t_hnsw_nr:.3f}s, size={size_hnsw_nr / 1024 / 1024:.1f}MB"
+    )
+    print("  Expectation: no-recompute should be faster but larger on disk.")
+
+    # ---------- DiskANN benchmark ----------
+    t_diskann_r = _bench_group(
+        diskann_r, True, "DiskANN R test doc 123", repeats=args.repeats, complexity=args.complexity
+    )
+    t_diskann_nr = _bench_group(
+        diskann_nr,
+        False,
+        "DiskANN NR test doc 123",
+        repeats=args.repeats,
+        complexity=args.complexity,
+    )
+    size_diskann_r = _size_for(diskann_r)
+    size_diskann_nr = _size_for(diskann_nr)
+
+    print("\nBenchmark results (DiskANN):")
+    print(f"  build(recompute=True, partition): size={size_diskann_r / 1024 / 1024:.1f}MB")
+    print(f"  build(recompute=False):          size={size_diskann_nr / 1024 / 1024:.1f}MB")
+    print(f"  search recompute=True (final rerank): {t_diskann_r:.3f}s")
+    print(f"  search recompute=False (PQ only):     {t_diskann_nr:.3f}s")
+
+
+if __name__ == "__main__":
+    main()

benchmarks/data/.gitattributes

@@ -1,82 +0,0 @@
-*.7z filter=lfs diff=lfs merge=lfs -text
-*.arrow filter=lfs diff=lfs merge=lfs -text
-*.bin filter=lfs diff=lfs merge=lfs -text
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-*.safetensors filter=lfs diff=lfs merge=lfs -text
-saved_model/**/* filter=lfs diff=lfs merge=lfs -text
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-# Audio files - uncompressed
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-# Audio files - compressed
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benchmarks/data/README.md

@@ -0,0 +1,44 @@
+---
+license: mit
+---
+
+# LEANN-RAG Evaluation Data
+
+This repository contains the necessary data to run the recall evaluation scripts for the [LEANN-RAG](https://huggingface.co/LEANN-RAG) project.
+
+## Dataset Components
+
+This dataset is structured into three main parts:
+
+1.  **Pre-built LEANN Indices**:
+    *   `dpr/`: A pre-built index for the DPR dataset.
+    *   `rpj_wiki/`: A pre-built index for the RPJ-Wiki dataset.
+    These indices were created using the `leann-core` library and are required by the `LeannSearcher`.
+
+2.  **Ground Truth Data**:
+    *   `ground_truth/`: Contains the ground truth files (`flat_results_nq_k3.json`) for both the DPR and RPJ-Wiki datasets. These files map queries to the original passage IDs from the Natural Questions benchmark, evaluated using the Contriever model.
+
+3.  **Queries**:
+    *   `queries/`: Contains the `nq_open.jsonl` file with the Natural Questions queries used for the evaluation.
+
+## Usage
+
+To use this data, you can download it locally using the `huggingface-hub` library. First, install the library:
+
+```bash
+pip install huggingface-hub
+```
+
+Then, you can download the entire dataset to a local directory (e.g., `data/`) with the following Python script:
+
+```python
+from huggingface_hub import snapshot_download
+
+snapshot_download(
+    repo_id="LEANN-RAG/leann-rag-evaluation-data",
+    repo_type="dataset",
+    local_dir="data"
+)
+```
+
+This will download all the necessary files into a local `data` folder, preserving the repository structure. The evaluation scripts in the main [LEANN-RAG Space](https://huggingface.co/LEANN-RAG) are configured to work with this data structure.

benchmarks/diskann_vs_hnsw_speed_comparison.py

@@ -0,0 +1,286 @@
+#!/usr/bin/env python3
+"""
+DiskANN vs HNSW Search Performance Comparison
+
+This benchmark compares search performance between DiskANN and HNSW backends:
+- DiskANN: With graph partitioning enabled (is_recompute=True)
+- HNSW: With recompute enabled (is_recompute=True)
+- Tests performance across different dataset sizes
+- Measures search latency, recall, and index size
+"""
+
+import gc
+import multiprocessing as mp
+import tempfile
+import time
+from pathlib import Path
+from typing import Any
+
+import numpy as np
+
+# Prefer 'fork' start method to avoid POSIX semaphore leaks on macOS
+try:
+    mp.set_start_method("fork", force=True)
+except Exception:
+    pass
+
+
+def create_test_texts(n_docs: int) -> list[str]:
+    """Create synthetic test documents for benchmarking."""
+    np.random.seed(42)
+    topics = [
+        "machine learning and artificial intelligence",
+        "natural language processing and text analysis",
+        "computer vision and image recognition",
+        "data science and statistical analysis",
+        "deep learning and neural networks",
+        "information retrieval and search engines",
+        "database systems and data management",
+        "software engineering and programming",
+        "cybersecurity and network protection",
+        "cloud computing and distributed systems",
+    ]
+
+    texts = []
+    for i in range(n_docs):
+        topic = topics[i % len(topics)]
+        variation = np.random.randint(1, 100)
+        text = (
+            f"This is document {i} about {topic}. Content variation {variation}. "
+            f"Additional information about {topic} with details and examples. "
+            f"Technical discussion of {topic} including implementation aspects."
+        )
+        texts.append(text)
+
+    return texts
+
+
+def benchmark_backend(
+    backend_name: str, texts: list[str], test_queries: list[str], backend_kwargs: dict[str, Any]
+) -> dict[str, float]:
+    """Benchmark a specific backend with the given configuration."""
+    from leann.api import LeannBuilder, LeannSearcher
+
+    print(f"\n🔧 Testing {backend_name.upper()} backend...")
+
+    with tempfile.TemporaryDirectory() as temp_dir:
+        index_path = str(Path(temp_dir) / f"benchmark_{backend_name}.leann")
+
+        # Build index
+        print(f"📦 Building {backend_name} index with {len(texts)} documents...")
+        start_time = time.time()
+
+        builder = LeannBuilder(
+            backend_name=backend_name,
+            embedding_model="facebook/contriever",
+            embedding_mode="sentence-transformers",
+            **backend_kwargs,
+        )
+
+        for text in texts:
+            builder.add_text(text)
+
+        builder.build_index(index_path)
+        build_time = time.time() - start_time
+
+        # Measure index size
+        index_dir = Path(index_path).parent
+        index_files = list(index_dir.glob(f"{Path(index_path).stem}.*"))
+        total_size = sum(f.stat().st_size for f in index_files if f.is_file())
+        size_mb = total_size / (1024 * 1024)
+
+        print(f"   ✅ Build completed in {build_time:.2f}s, index size: {size_mb:.1f}MB")
+
+        # Search benchmark
+        print("🔍 Running search benchmark...")
+        searcher = LeannSearcher(index_path)
+
+        search_times = []
+        all_results = []
+
+        for query in test_queries:
+            start_time = time.time()
+            results = searcher.search(query, top_k=5)
+            search_time = time.time() - start_time
+            search_times.append(search_time)
+            all_results.append(results)
+
+        avg_search_time = np.mean(search_times) * 1000  # Convert to ms
+        print(f"   ✅ Average search time: {avg_search_time:.1f}ms")
+
+        # Check for valid scores (detect -inf issues)
+        all_scores = [
+            result.score
+            for results in all_results
+            for result in results
+            if result.score is not None
+        ]
+        valid_scores = [
+            score for score in all_scores if score != float("-inf") and score != float("inf")
+        ]
+        score_validity_rate = len(valid_scores) / len(all_scores) if all_scores else 0
+
+        # Clean up (ensure embedding server shutdown and object GC)
+        try:
+            if hasattr(searcher, "cleanup"):
+                searcher.cleanup()
+            del searcher
+            del builder
+            gc.collect()
+        except Exception as e:
+            print(f"⚠️  Warning: Resource cleanup error: {e}")
+
+        return {
+            "build_time": build_time,
+            "avg_search_time_ms": avg_search_time,
+            "index_size_mb": size_mb,
+            "score_validity_rate": score_validity_rate,
+        }
+
+
+def run_comparison(n_docs: int = 500, n_queries: int = 10):
+    """Run performance comparison between DiskANN and HNSW."""
+    print("🚀 Starting DiskANN vs HNSW Performance Comparison")
+    print(f"📊 Dataset: {n_docs} documents, {n_queries} test queries")
+
+    # Create test data
+    texts = create_test_texts(n_docs)
+    test_queries = [
+        "machine learning algorithms",
+        "natural language processing",
+        "computer vision techniques",
+        "data analysis methods",
+        "neural network architectures",
+        "database query optimization",
+        "software development practices",
+        "security vulnerabilities",
+        "cloud infrastructure",
+        "distributed computing",
+    ][:n_queries]
+
+    # HNSW benchmark
+    hnsw_results = benchmark_backend(
+        backend_name="hnsw",
+        texts=texts,
+        test_queries=test_queries,
+        backend_kwargs={
+            "is_recompute": True,  # Enable recompute for fair comparison
+            "M": 16,
+            "efConstruction": 200,
+        },
+    )
+
+    # DiskANN benchmark
+    diskann_results = benchmark_backend(
+        backend_name="diskann",
+        texts=texts,
+        test_queries=test_queries,
+        backend_kwargs={
+            "is_recompute": True,  # Enable graph partitioning
+            "num_neighbors": 32,
+            "search_list_size": 50,
+        },
+    )
+
+    # Performance comparison
+    print("\n📈 Performance Comparison Results")
+    print(f"{'=' * 60}")
+    print(f"{'Metric':<25} {'HNSW':<15} {'DiskANN':<15} {'Speedup':<10}")
+    print(f"{'-' * 60}")
+
+    # Build time comparison
+    build_speedup = hnsw_results["build_time"] / diskann_results["build_time"]
+    print(
+        f"{'Build Time (s)':<25} {hnsw_results['build_time']:<15.2f} {diskann_results['build_time']:<15.2f} {build_speedup:<10.2f}x"
+    )
+
+    # Search time comparison
+    search_speedup = hnsw_results["avg_search_time_ms"] / diskann_results["avg_search_time_ms"]
+    print(
+        f"{'Search Time (ms)':<25} {hnsw_results['avg_search_time_ms']:<15.1f} {diskann_results['avg_search_time_ms']:<15.1f} {search_speedup:<10.2f}x"
+    )
+
+    # Index size comparison
+    size_ratio = diskann_results["index_size_mb"] / hnsw_results["index_size_mb"]
+    print(
+        f"{'Index Size (MB)':<25} {hnsw_results['index_size_mb']:<15.1f} {diskann_results['index_size_mb']:<15.1f} {size_ratio:<10.2f}x"
+    )
+
+    # Score validity
+    print(
+        f"{'Score Validity (%)':<25} {hnsw_results['score_validity_rate'] * 100:<15.1f} {diskann_results['score_validity_rate'] * 100:<15.1f}"
+    )
+
+    print(f"{'=' * 60}")
+    print("\n🎯 Summary:")
+    if search_speedup > 1:
+        print(f"   DiskANN is {search_speedup:.2f}x faster than HNSW for search")
+    else:
+        print(f"   HNSW is {1 / search_speedup:.2f}x faster than DiskANN for search")
+
+    if size_ratio > 1:
+        print(f"   DiskANN uses {size_ratio:.2f}x more storage than HNSW")
+    else:
+        print(f"   DiskANN uses {1 / size_ratio:.2f}x less storage than HNSW")
+
+    print(
+        f"   Both backends achieved {min(hnsw_results['score_validity_rate'], diskann_results['score_validity_rate']) * 100:.1f}% score validity"
+    )
+
+
+if __name__ == "__main__":
+    import sys
+
+    try:
+        # Handle help request
+        if len(sys.argv) > 1 and sys.argv[1] in ["-h", "--help", "help"]:
+            print("DiskANN vs HNSW Performance Comparison")
+            print("=" * 50)
+            print(f"Usage: python {sys.argv[0]} [n_docs] [n_queries]")
+            print()
+            print("Arguments:")
+            print("  n_docs      Number of documents to index (default: 500)")
+            print("  n_queries   Number of test queries to run (default: 10)")
+            print()
+            print("Examples:")
+            print("  python benchmarks/diskann_vs_hnsw_speed_comparison.py")
+            print("  python benchmarks/diskann_vs_hnsw_speed_comparison.py 1000")
+            print("  python benchmarks/diskann_vs_hnsw_speed_comparison.py 2000 20")
+            sys.exit(0)
+
+        # Parse command line arguments
+        n_docs = int(sys.argv[1]) if len(sys.argv) > 1 else 500
+        n_queries = int(sys.argv[2]) if len(sys.argv) > 2 else 10
+
+        print("DiskANN vs HNSW Performance Comparison")
+        print("=" * 50)
+        print(f"Dataset: {n_docs} documents, {n_queries} queries")
+        print()
+
+        run_comparison(n_docs=n_docs, n_queries=n_queries)
+
+    except KeyboardInterrupt:
+        print("\n⚠️  Benchmark interrupted by user")
+        sys.exit(130)
+    except Exception as e:
+        print(f"\n❌ Benchmark failed: {e}")
+        sys.exit(1)
+    finally:
+        # Ensure clean exit (forceful to prevent rare hangs from atexit/threads)
+        try:
+            gc.collect()
+            print("\n🧹 Cleanup completed")
+            # Flush stdio to ensure message is visible before hard-exit
+            try:
+                import sys as _sys
+
+                _sys.stdout.flush()
+                _sys.stderr.flush()
+            except Exception:
+                pass
+        except Exception:
+            pass
+        # Use os._exit to bypass atexit handlers that may hang in rare cases
+        import os as _os
+
+        _os._exit(0)

benchmarks/run_evaluation.py

@@ -12,7 +12,7 @@ import time
 from pathlib import Path
 
 import numpy as np
-from leann.api import LeannBuilder, LeannSearcher
+from leann.api import LeannBuilder, LeannChat, LeannSearcher
 
 
 def download_data_if_needed(data_root: Path, download_embeddings: bool = False):
@@ -197,6 +197,25 @@ def main():
     parser.add_argument(
         "--ef-search", type=int, default=120, help="The 'efSearch' parameter for HNSW."
     )
+    parser.add_argument(
+        "--batch-size",
+        type=int,
+        default=0,
+        help="Batch size for HNSW batched search (0 disables batching)",
+    )
+    parser.add_argument(
+        "--llm-type",
+        type=str,
+        choices=["ollama", "hf", "openai", "gemini", "simulated"],
+        default="ollama",
+        help="LLM backend type to optionally query during evaluation (default: ollama)",
+    )
+    parser.add_argument(
+        "--llm-model",
+        type=str,
+        default="qwen3:1.7b",
+        help="LLM model identifier for the chosen backend (default: qwen3:1.7b)",
+    )
     args = parser.parse_args()
 
     # --- Path Configuration ---
@@ -318,9 +337,24 @@ def main():
 
         for i in range(num_eval_queries):
             start_time = time.time()
-            new_results = searcher.search(queries[i], top_k=args.top_k, ef=args.ef_search)
+            new_results = searcher.search(
+                queries[i],
+                top_k=args.top_k,
+                complexity=args.ef_search,
+                batch_size=args.batch_size,
+            )
             search_times.append(time.time() - start_time)
 
+            # Optional: also call the LLM with configurable backend/model (does not affect recall)
+            llm_config = {"type": args.llm_type, "model": args.llm_model}
+            chat = LeannChat(args.index_path, llm_config=llm_config, searcher=searcher)
+            answer = chat.ask(
+                queries[i],
+                top_k=args.top_k,
+                complexity=args.ef_search,
+                batch_size=args.batch_size,
+            )
+            print(f"Answer: {answer}")
             # Correct Recall Calculation: Based on TEXT content
             new_texts = {result.text for result in new_results}
 

benchmarks/simple_mac_tpt_test.py

@@ -20,7 +20,7 @@ except ImportError:
 
 @dataclass
 class BenchmarkConfig:
-    model_path: str = "facebook/contriever"
+    model_path: str = "facebook/contriever-msmarco"
     batch_sizes: list[int] = None
     seq_length: int = 256
     num_runs: int = 5
@@ -34,7 +34,7 @@ class BenchmarkConfig:
 
     def __post_init__(self):
         if self.batch_sizes is None:
-            self.batch_sizes = [1, 2, 4, 8, 16, 32, 64]
+            self.batch_sizes = [1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024]
 
 
 class MLXBenchmark:
@@ -179,10 +179,16 @@ class Benchmark:
 
     def _run_inference(self, input_ids: torch.Tensor) -> float:
         attention_mask = torch.ones_like(input_ids)
-
+        # print shape of input_ids and attention_mask
+        print(f"input_ids shape: {input_ids.shape}")
+        print(f"attention_mask shape: {attention_mask.shape}")
         start_time = time.time()
         with torch.no_grad():
             self.model(input_ids=input_ids, attention_mask=attention_mask)
+        if torch.cuda.is_available():
+            torch.cuda.synchronize()
+        if torch.backends.mps.is_available():
+            torch.mps.synchronize()
         end_time = time.time()
 
         return end_time - start_time

data/huawei_pangu.md

@@ -0,0 +1,82 @@
+# 盘古之殇：华为诺亚盘古大模型研发历程的心酸与黑暗
+
+各位好，
+
+我是一名盘古大模型团队，华为诺亚方舟实验室的员工。
+
+首先为自证身份，列举一些细节：
+
+1. 现诺亚主任，前算法应用部部长，后改名为小模型实验室的主任王云鹤。前诺亚主任：姚骏（大家称姚老师）。几个实验室主任：唐睿明（明哥，明队，已离职），尚利峰，张维（维哥），郝建业（郝老师），刘武龙（称呼为武龙所）等。其他骨干成员和专家陆续有很多人离职。
+2. 我们隶属于“四野”这个组织。四野下属有许多纵队，基础语言大模型是四纵。王云鹤的小模型是十六纵队。我们参加过苏州的集结，有各种月份的时间节点。在苏州攻关会颁发任务令，需要在节点前达成目标。苏州集结会把各地的人员都集中在苏州研究所，平常住宾馆，比如在甪直的酒店，与家人孩子天各一方。
+3. 在苏州集结的时候周六默认上班，非常辛苦，不过周六有下午茶，有一次还有小龙虾。在苏州研究所的工位搬迁过一次，从一栋楼换到了另一栋。苏州研究所楼栋都是欧式装修，门口有大坡，里面景色很不错。去苏州集结一般至少要去一周，甚至更久，多的人甚至一两个月都回不了家。
+4. 诺亚曾经传说是研究型的，但是来了之后因为在四野做大模型项目，项目成员完全变成了交付型的，且充满了例会，评审，汇报。很多时候做实验都要申请。团队需要对接终端小艺，华为云，ICT等诸多业务线，交付压力不小。
+5. 诺亚研发的盘古模型早期内部代号叫做“盘古智子”，一开始只有内部需要申请试用的网页版，到后续迫于压力在welink上接入和公测开放。
+
+这些天发生关于质疑盘古大模型抄袭千问的事情闹的沸沸扬扬。作为一个盘古团队的成员，我最近夜夜辗转反侧，难以入眠。盘古的品牌受到如此大的影响，一方面，我自私的为我的职业发展担忧，也为自己过去的努力工作感到不值。另一方面，由于有人开始揭露这些事情我内心又感到大快人心。在多少个日日夜夜，我们对内部某些人一次次靠着造假而又获得了无数利益的行为咬牙切齿而又无能为力。这种压抑和羞辱也逐渐消磨了我对华为的感情，让我在这里的时日逐渐浑浑噩噩，迷茫无措，时常怀疑自己的人生和自我价值。
+
+我承认我是一个懦弱的人，作为一个小小的打工人，我不仅不敢和王云鹤等内部手眼通天的人做对，更不敢和华为这样的庞然大物做对。我很怕失去我的工作，毕竟我也有家人和孩子，所以我打心眼里很佩服揭露者。但是，看到内部还在试图洗地掩盖事实，蒙蔽公众的时候，我实在不能容忍了。我也希望勇敢一次，顺从自己本心。就算自损八百，我也希望能伤敌一千。我决定把我在这里的所见所闻（部分来自于同事口述）公布出来，关于盘古大模型的“传奇故事”：
+
+华为确实主要在昇腾卡上训练大模型（小模型实验室有不少英伟达的卡，他们之前也会用来训练，后面转移到昇腾）。曾经我被华为“打造世界第二选择”的决心而折服，我本身也曾经对华为有深厚的感情。我们陪着昇腾一步步摸爬滚打，从充满bug到现在能训出模型，付出了巨大的心血和代价。
+
+最初我们的算力非常有限，在910A上训练模型。那会只支持fp16，训练的稳定性远不如bf16。盘古的moe开始很早，23年就主要是训练38Bmoe模型和后续的71B dense模型。71B的dense模型通过扩增变成了第一代的135Bdense模型，后面主力模型也逐渐在910B上训练。
+
+71B和135B模型都有一个巨大的硬伤就是tokenizer。当时使用的tokenizer编码效率极低，每个单个的符号，数字，空格，乃至汉字都会占用一个token。可想而知这会非常浪费算力，且使得模型的效果很差。这时候小模型实验室正好有个自己训的词表。姚老师当时怀疑是不是模型的tokenizer不好（虽然事后来看，他的怀疑是无疑正确的），于是就决定，让71B和135B换tokenizer，因为小模型实验室曾经尝试过。团队缝合了两个tokenizer，开始了tokenizer的更换。71B模型的更换失败了，而135B因为采用了更精细的embedding初始化策略，续训了至少1T的数据后词表总算更换成功，但可想而知，效果并不会变好。
+
+于此同期，阿里和智谱等国内其他公司在GPU上训练，且已经摸索出了正确的方法，盘古和竞品的差距越来越大。内部一个230B从头训练的dense模型又因为各种原因训练失败，导致项目的状况几乎陷入绝境。面临几个节点的压力以及内部对盘古的强烈质疑时，团队的士气低迷到了极点。团队在算力极其有限的时候，做出了很多努力和挣扎。比如，团队偶然发现当时的38B moe并没有预期moe的效果。于是去掉了moe参数，还原为了13B的dense模型。由于38B的moe源自很早的pangu alpha 13B，架构相对落后，团队进行了一系列的操作，比如切换绝对位置编码到rope，去掉bias，切换为rmsnorm。同时鉴于tokenizer的一些失败和换词表的经验，这个模型的词表也更换为了王云鹤的小模型实验室7B模型所使用的词表。后面这个13B模型进行了扩增续训，变成了第二代38B dense模型（在几个月内这个模型都是主要的盘古中档位模型），曾经具有一定的竞争力。但是，由于更大的135B模型架构落后，且更换词表模型损伤巨大（后续分析发现当时更换的缝合词表有更严重的bug），续训后也与千问等当时国内领先模型存在很大差距。这时由于内部的质疑声和领导的压力也越来越大。团队的状态几乎陷入了绝境。
+
+在这种情况下，王云鹤和他的小模型实验室出手了。他们声称是从旧的135B参数继承改造而来，通过训练短短的几百B数据，各项指标平均提升了十个点左右。实际上，这就是他们套壳应用到大模型的第一次杰作。华为的外行领导内行，使得领导完全对于这种扯淡的事情没有概念，他们只会觉得肯定是有什么算法创新。经过内部的分析，他们实际上是使用Qwen 1.5 110B续训而来，通过加层，扩增ffn维度，添加盘古pi论文的一些机制得来，凑够了大概135B的参数。实际上，旧的135B有107层，而这个模型只有82层，各种配置也都不一样。新的来路不明的135B训练完很多参数的分布也和Qwen 110B几乎一模一样。连模型代码的类名当时都是Qwen，甚至懒得改名。后续这个模型就是所谓的135B V2。而这个模型当时也提供给了很多下游，甚至包括外部客户。
+
+这件事对于我们这些认真诚实做事的同事们带来了巨大的冲击，内部很多人其实都知道这件事，甚至包括终端和华为云。我们都戏称以后别叫盘古模型了，叫千古吧。当时团队成员就想向bcg举报了，毕竟这已经是重大的业务造假了。但是后面据说被领导拦了下来，因为更高级别的领导（比如姚老师，以及可能熊总和查老）其实后面也知道了，但是并不管，因为通过套壳拿出好的结果，对他们也是有利的。这件事使得当时团队几位最强的同事开始心灰意冷，离职跑路也逐渐成为挂在嘴边的事。
+
+此时，盘古似乎迎来了转机。由于前面所述的这些盘古模型基本都是续训和改造而来，当时诺亚完全没有掌握从头训练的技术，何况还是在昇腾的NPU上进行训练。在当时团队的核心成员的极力争取下，盘古开始了第三代模型的训练，付出了巨大的努力后，在数据架构和训练算法方面都与业界逐渐接轨，而这其中的艰辛和小模型实验室的人一点关系都没有。
+
+一开始团队成员毫无信心，只从一个13B的模型开始训练，但是后面发现效果还不错，于是这个模型后续再次进行了一次参数扩增，变成了第三代的38B，代号38B V3。想必很多产品线的兄弟都对这个模型很熟悉。当时这个模型的tokenizer是基于llama的词表进行扩展的（也是业界常见的做法）。而当时王云鹤的实验室做出来了另一个词表（也就是后续pangu系列的词表）。当时两个词表还被迫进行了一次赛马，最终没有明显的好坏结论。于是，领导当即决定，应该统一词表，使用王云鹤他们的。于是，在后续从头训练的135B V3（也就是对外的Pangu Ultra），便是采用了这个tokenizer。这也解释了很多使用我们模型的兄弟的疑惑，为什么当时同为V3代的两个不同档位的模型，会使用不同的tokenizer。
+
+
+我们打心眼里觉得，135B V3是我们四纵团队当时的骄傲。这是第一个真正意义上的，华为全栈自研，正经从头训练的千亿级别的模型，且效果与24年同期竞品可比的。写到这里我已经热泪盈眶，太不容易了。当时为了稳定训练，团队做了大量实验对比，并且多次在模型梯度出现异常的时候进行及时回退重启。这个模型真正做到了后面技术报告所说的训练全程没有一个loss spike。我们克服了不知道多少困难，我们做到了，我们愿用生命和荣誉保证这个模型训练的真实性。多少个凌晨，我们为了它的训练而不眠。在被内部心声骂的一文不值的时候，我们有多么不甘，有多少的委屈，我们挺住了。
+
+我们这帮人是真的在为打磨国产算力底座燃烧自己的青春啊……客居他乡，我们放弃了家庭，放弃了假期，放弃了健康，放弃了娱乐，抛头颅洒热血，其中的艰辛与困苦，寥寥数笔不足以概括其万一。在各种动员大会上，当时口号中喊出的盘古必胜，华为必胜，我们心里是真的深深被感动。
+
+然而，我们的所有辛苦的成果，经常被小模型实验室轻飘飘的拿走了。数据，直接要走。代码，直接要走，还要求我们配合适配到能一键运行。我们当时戏称小模型实验室为点鼠标实验室。我们付出辛苦，他们取得荣耀。果然应了那句话，你在负重前行是因为有人替你岁月静好。在这种情况下，越来越多的战友再也坚持不下去了，选择了离开。看到身边那些优秀的同事一个个离职，我的内心又感叹又难过。在这种作战一样的环境下，我们比起同事来说更像是战友。他们在技术上也有无数值得我学习的地方，堪称良师。看到他们去了诸如字节Seed，Deepseek，月之暗面，腾讯和快手等等很多出色的团队，我打心眼里为他们高兴和祝福，脱离了这个辛苦却肮脏的地方。我至今还对一位离职同事的话记忆犹新，ta说：“来这里是我技术生涯中的耻辱，在这里再呆每一天都是浪费生命”。话虽难听却让我无言以对。我担心我自己技术方面的积累不足，以及没法适应互联网公司高淘汰的环境，让我多次想离职的心始终没有迈出这一步。
+
+盘古除了dense模型，后续也启动了moe的探索。一开始训练的是一个224B的moe模型。而与之平行的，小模型实验室也开启了第二次主要的套壳行动（次要的插曲可能还包括一些别的模型，比如math模型），即这次流传甚广的pangu pro moe 72B。这个模型内部自称是从小模型实验室的7B扩增上来的（就算如此，这也与技术报告不符，何况是套壳qwen 2.5的14b续训）。还记得他们训了没几天，内部的评测就立刻追上了当时的38B V3。AI系统实验室很多兄弟因为需要适配模型，都知道他们的套壳行动，只是迫于各种原因，无法伸张正义。实际上，对于后续训了很久很久的这个模型，Honestagi能够分析出这个量级的相似性我已经很诧异了，因为这个模型为了续训洗参数，所付出的算力甚至早就足够从头训一个同档位的模型了。听同事说他们为了洗掉千问的水印，采取了不少办法，甚至包括故意训了脏数据。这也为学术界研究模型血缘提供了一个前所未有的特殊模范吧。以后新的血缘方法提出可以拿出来溜溜。
+
+24年底和25年初，在Deepseek v3和r1发布之后，由于其惊艳的技术水平，团队受到了巨大的冲击，也受到了更大的质疑。于是为了紧跟潮流，盘古模仿Deepseek的模型尺寸，开启了718B moe的训练。这个时候，小模型实验室再次出手了。他们选择了套壳Deepseekv3续训。他们通过冻住Deepseek加载的参数，进行训练。连任务加载ckpt的目录都是deepseekv3，改都不改，何其嚣张？与之相反，一些有真正技术信仰的同事，在从头训练另一个718B的moe。但其中出现了各种各样的问题。但是很显然，这个模型怎么可能比直接套壳的好呢？如果不是团队leader坚持，早就被叫停了。
+
+华为的流程管理之繁重，严重拖累了大模型的研发节奏，例如版本管理，模型血缘，各种流程化，各种可追溯。讽刺的是，小模型实验室的模型似乎从来不受这些流程的约束，想套壳就套壳，想续训就续训，算力源源不断的伸手拿走。这种强烈到近乎魔幻的对比，说明了当前流程管理的情况：只许州官放火，不许百姓点灯。何其可笑？何其可悲？何其可恶？何其可耻！
+
+HonestAGI的事情出来后，内部让大家不停的研讨分析，如何公关和“回应”。诚然，这个原文的分析也许不够有力，给了王云鹤与小模型实验室他们狡辩和颠倒黑白的机会。为此，这两天我内心感到作呕，时时怀疑自己的人生意义以及苍天无眼。我不奉陪了，我要离职了，同时我也在申请从盘古部分技术报告的作者名单中移除。曾经在这些技术报告上署名是我一生都无法抹除的污点。当时我没想到，他们竟然猖狂到敢开源。我没想到，他们敢如此愚弄世人，大肆宣发。当时，我也许是存了侥幸心理，没有拒绝署名。我相信很多扎实做事的战友，也只是被迫上了贼船，或者不知情。但这件事已经无法挽回，我希望我的余生能够坚持扎实做真正有意义的事，为我当时的软弱和不坚定赎罪。
+
+深夜写到这里，我已经泪流满面，泣不成声。还记得一些出色的同事离职时，我苦笑问他们要不要发个长长的心声惯例帖，揭露一下现状。对方说：不了，浪费时间，而且我也怕揭露出来你们过的更糟。我当时一下黯然神伤，因为曾经共同为了理想奋斗过的战友已经彻底对华为彻底灰心了。当时大家调侃，我们用着当年共产党的小米加步枪，组织却有着堪比当年国民党的作风。
+
+曾几何时，我为我们用着小米加步枪打败洋枪洋炮而自豪。
+
+现在，我累了，我想投降。
+
+其实时至今日，我还是真心希望华为能认真吸取教训，能做好盘古，把盘古做到世界一流，把昇腾变成英伟达的水平。内部的劣币驱逐良币，使得诺亚乃至华为在短时间内急剧流失了大量出色的大模型人才。相信他们也正在如Deepseek等各个团队闪耀着，施展着他们的抱负才华，为中美在AI的激烈竞赛中奉献力量。我时常感叹，华为不是没有人才，而是根本不知道怎么留住人才。如果给这些人合适的环境，合适的资源，更少的枷锁，更少的政治斗争，盘古何愁不成？
+
+最后：我以生命，人格和荣誉发誓，我写的以上所有内容均为真实（至少在我有限的认知范围内）。我没有那么高的技术水平以及机会去做详尽扎实的分析，也不敢直接用内部记录举证，怕因为信息安全抓到。但是我相信我很多曾经的战友，会为我作证。在华为内部的兄弟，包括我们曾经服务过的产品线兄弟们，相信本文的无数细节能和你们的印象对照，印证我的说法。你们可能也曾经被蒙骗，但这些残酷的真相不会被尘封。我们奋战过的痕迹，也不应该被扭曲和埋葬。
+
+写了这么多，某些人肯定想把我找出来，抹杀掉。公司搞不好也想让我噤声乃至追责。如果真的这样，我，乃至我的家人的人身乃至生命安全可能都会受到威胁。为了自我保护，我近期每天会跟大家报平安。
+
+如果我消失了，就当是我为了真理和理想，为了华为乃至中国能够更好地发展算力和AI而牺牲了吧，我愿埋葬于那片曾经奋斗过的地方。
+
+诺亚，再见
+
+2025年7月6日凌晨      写于深圳
+
+---
+
+各位好，
+
+感谢大家的关心与祝福。我目前暂时安全，但公司应该在进行排查与某些名单收集，后续情况未知。
+
+我补充一些细节，以免某些人继续颠倒黑白。
+
+关于135B V2，小模型实验室在迅速地完成套壳并拿完所有套壳带来的好处后（比如任务令表彰和及时激励），因为不想继续支撑下游应用和模型迭代，又把这个烫手山芋甩给了四纵。确实技高一筹，直接把四纵的兄弟们拉下水。同事提供过去一个老旧的模型，最终拿回了一个当时一个魔改的先进的千问。做大模型的人，自己做的模型就像自己孩子一样熟悉，不要把别人都当傻子。就像自家儿子出门一趟，回来个别人家孩子。
+
+盘古report的署名是不符合学术规范的。例如，135B V3有不少有技术贡献的人，因为作者名额数量限制，劳动成果没有得到应有的回报，团队内曾经有不小的意见。这个模型当时是大家智慧和汗水的结晶，甚至是团队当时的精神支柱，支撑着不少兄弟们继续留在诺亚。所谓的名额限制，以及挂名了一些毫无技术贡献的人（如一些小模型实验室的人），让兄弟们何其心寒。
+
+---
+
+暂时平安。另外，支持我勇于说出真相的战友们 https://github.com/HW-whistleblower/True-Story-of-Pangu/issues/317

docs/ast_chunking_guide.md

@@ -0,0 +1,143 @@
+# AST-Aware Code chunking guide
+
+## Overview
+
+This guide covers best practices for using AST-aware code chunking in LEANN. AST chunking provides better semantic understanding of code structure compared to traditional text-based chunking.
+
+## Quick Start
+
+### Basic Usage
+
+```bash
+# Enable AST chunking for mixed content (code + docs)
+python -m apps.document_rag --enable-code-chunking --data-dir ./my_project
+
+# Specialized code repository indexing
+python -m apps.code_rag --repo-dir ./my_codebase
+
+# Global CLI with AST support
+leann build my-code-index --docs ./src --use-ast-chunking
+```
+
+### Installation
+
+```bash
+# Install LEANN with AST chunking support
+uv pip install -e "."
+```
+
+#### For normal users (PyPI install)
+- Use `pip install leann` or `uv pip install leann`.
+- `astchunk` is pulled automatically from PyPI as a dependency; no extra steps.
+
+#### For developers (from source, editable)
+```bash
+git clone https://github.com/yichuan-w/LEANN.git leann
+cd leann
+git submodule update --init --recursive
+uv sync
+```
+- This repo vendors `astchunk` as a git submodule at `packages/astchunk-leann` (our fork).
+- `[tool.uv.sources]` maps the `astchunk` package to that path in editable mode.
+- You can edit code under `packages/astchunk-leann` and Python will use your changes immediately (no separate `pip install astchunk` needed).
+
+## Best Practices
+
+### When to Use AST Chunking
+
+✅ **Recommended for:**
+- Code repositories with multiple languages
+- Mixed documentation and code content
+- Complex codebases with deep function/class hierarchies
+- When working with Claude Code for code assistance
+
+❌ **Not recommended for:**
+- Pure text documents
+- Very large files (>1MB)
+- Languages not supported by tree-sitter
+
+### Optimal Configuration
+
+```bash
+# Recommended settings for most codebases
+python -m apps.code_rag \
+    --repo-dir ./src \
+    --ast-chunk-size 768 \
+    --ast-chunk-overlap 96 \
+    --exclude-dirs .git __pycache__ node_modules build dist
+```
+
+### Supported Languages
+
+| Extension | Language | Status |
+|-----------|----------|--------|
+| `.py` | Python | ✅ Full support |
+| `.java` | Java | ✅ Full support |
+| `.cs` | C# | ✅ Full support |
+| `.ts`, `.tsx` | TypeScript | ✅ Full support |
+| `.js`, `.jsx` | JavaScript | ✅ Via TypeScript parser |
+
+## Integration Examples
+
+### Document RAG with Code Support
+
+```python
+# Enable code chunking in document RAG
+python -m apps.document_rag \
+    --enable-code-chunking \
+    --data-dir ./project \
+    --query "How does authentication work in the codebase?"
+```
+
+### Claude Code Integration
+
+When using with Claude Code MCP server, AST chunking provides better context for:
+- Code completion and suggestions
+- Bug analysis and debugging
+- Architecture understanding
+- Refactoring assistance
+
+## Troubleshooting
+
+### Common Issues
+
+1. **Fallback to Traditional Chunking**
+   - Normal behavior for unsupported languages
+   - Check logs for specific language support
+
+2. **Performance with Large Files**
+   - Adjust `--max-file-size` parameter
+   - Use `--exclude-dirs` to skip unnecessary directories
+
+3. **Quality Issues**
+   - Try different `--ast-chunk-size` values (512, 768, 1024)
+   - Adjust overlap for better context preservation
+
+### Debug Mode
+
+```bash
+export LEANN_LOG_LEVEL=DEBUG
+python -m apps.code_rag --repo-dir ./my_code
+```
+
+## Migration from Traditional Chunking
+
+Existing workflows continue to work without changes. To enable AST chunking:
+
+```bash
+# Before
+python -m apps.document_rag --chunk-size 256
+
+# After (maintains traditional chunking for non-code files)
+python -m apps.document_rag --enable-code-chunking --chunk-size 256 --ast-chunk-size 768
+```
+
+## References
+
+- [astchunk GitHub Repository](https://github.com/yilinjz/astchunk)
+- [LEANN MCP Integration](../packages/leann-mcp/README.md)
+- [Research Paper](https://arxiv.org/html/2506.15655v1)
+
+---
+
+**Note**: AST chunking maintains full backward compatibility while enhancing code understanding capabilities.

docs/configuration-guide.md

@@ -52,7 +52,7 @@ Based on our experience developing LEANN, embedding models fall into three categ
 ### Quick Start: Cloud and Local Embedding Options
 
 **OpenAI Embeddings (Fastest Setup)**
-For immediate testing without local model downloads:
+For immediate testing without local model downloads(also if you [do not have GPU](https://github.com/yichuan-w/LEANN/issues/43) and do not care that much about your document leak, you should use this, we compute the embedding and recompute using openai API):
 ```bash
 # Set OpenAI embeddings (requires OPENAI_API_KEY)
 --embedding-mode openai --embedding-model text-embedding-3-small
@@ -97,16 +97,24 @@ ollama pull nomic-embed-text
 ```
 
 ### DiskANN
-**Best for**: Large datasets (> 10M vectors, 10GB+ index size) - **⚠️ Beta version, still in active development**
-- Uses Product Quantization (PQ) for coarse filtering during graph traversal
-- Novel approach: stores only PQ codes, performs rerank with exact computation in final step
-- Implements a corner case of double-queue: prunes all neighbors and recomputes at the end
+**Best for**: Large datasets, especially when you want `recompute=True`.
+
+**Key advantages:**
+- **Faster search** on large datasets (3x+ speedup vs HNSW in many cases)
+- **Smart storage**: `recompute=True` enables automatic graph partitioning for smaller indexes
+- **Better scaling**: Designed for 100k+ documents
+
+**Recompute behavior:**
+- `recompute=True` (recommended): Pure PQ traversal + final reranking - faster and enables partitioning
+- `recompute=False`: PQ + partial real distances during traversal - slower but higher accuracy
 
 ```bash
-# For billion-scale deployments
---backend-name diskann --graph-degree 64 --build-complexity 128
+# Recommended for most use cases
+--backend-name diskann --graph-degree 32 --build-complexity 64
 ```
 
+**Performance Benchmark**: Run `uv run benchmarks/diskann_vs_hnsw_speed_comparison.py` to compare DiskANN and HNSW on your system.
+
 ## LLM Selection: Engine and Model Comparison
 
 ### LLM Engines
@@ -222,9 +230,15 @@ python apps/document_rag.py --query "What are the main techniques LEANN explores
 
 3. **Use MLX on Apple Silicon** (optional optimization):
    ```bash
-   --embedding-mode mlx --embedding-model mlx-community/multilingual-e5-base-mlx
+   --embedding-mode mlx --embedding-model mlx-community/Qwen3-Embedding-0.6B-8bit
    ```
+    MLX might not be the best choice, as we tested and found that it only offers 1.3x acceleration compared to HF, so maybe using ollama is a better choice for embedding generation
 
+4. **Use Ollama**
+   ```bash
+   --embedding-mode ollama --embedding-model nomic-embed-text
+   ```
+   To discover additional embedding models in ollama, check out https://ollama.com/search?c=embedding or read more about embedding models at https://ollama.com/blog/embedding-models, please do check the model size that works best for you
 ### If Search Quality is Poor
 
 1. **Increase retrieval count**:
@@ -253,27 +267,118 @@ Every configuration choice involves trade-offs:
 
 The key is finding the right balance for your specific use case. Start small and simple, measure performance, then scale up only where needed.
 
-## Deep Dive: Critical Configuration Decisions
+## Low-resource setups
 
-### When to Disable Recomputation
+If you don’t have a local GPU or builds/searches are too slow, use one or more of the options below.
 
-LEANN's recomputation feature provides exact distance calculations but can be disabled for extreme QPS requirements:
+### 1) Use OpenAI embeddings (no local compute)
+
+Fastest path with zero local GPU requirements. Set your API key and use OpenAI embeddings during build and search:
 
 ```bash
---no-recompute  # Disable selective recomputation
+export OPENAI_API_KEY=sk-...
+
+# Build with OpenAI embeddings
+leann build my-index \
+  --embedding-mode openai \
+  --embedding-model text-embedding-3-small
+
+# Search with OpenAI embeddings (recompute at query time)
+leann search my-index "your query" \
+  --recompute
 ```
 
-**Trade-offs**:
-- **With recomputation** (default): Exact distances, best quality, higher latency, minimal storage (only stores metadata, recomputes embeddings on-demand)
-- **Without recomputation**: Must store full embeddings, significantly higher memory and storage usage (10-100x more), but faster search
+### 2) Run remote builds with SkyPilot (cloud GPU)
+
+Offload embedding generation and index building to a GPU VM using [SkyPilot](https://skypilot.readthedocs.io/en/latest/). A template is provided at `sky/leann-build.yaml`.
+
+```bash
+# One-time: install and configure SkyPilot
+pip install skypilot
+
+# Launch with defaults (L4:1) and mount ./data to ~/leann-data; the build runs automatically
+sky launch -c leann-gpu sky/leann-build.yaml
+
+# Override parameters via -e key=value (optional)
+sky launch -c leann-gpu sky/leann-build.yaml \
+  -e index_name=my-index \
+  -e backend=hnsw \
+  -e embedding_mode=sentence-transformers \
+  -e embedding_model=Qwen/Qwen3-Embedding-0.6B
+
+# Copy the built index back to your local .leann (use rsync)
+rsync -Pavz leann-gpu:~/.leann/indexes/my-index ./.leann/indexes/
+```
+
+### 3) Disable recomputation to trade storage for speed
+
+If you need lower latency and have more storage/memory, disable recomputation. This stores full embeddings and avoids recomputing at search time.
+
+```bash
+# Build without recomputation (HNSW requires non-compact in this mode)
+leann build my-index --no-recompute --no-compact
+
+# Search without recomputation
+leann search my-index "your query" --no-recompute
+```
+
+When to use:
+- Extreme low latency requirements (high QPS, interactive assistants)
+- Read-heavy workloads where storage is cheaper than latency
+- No always-available GPU
+
+Constraints:
+- HNSW: when `--no-recompute` is set, LEANN automatically disables compact mode during build
+- DiskANN: supported; `--no-recompute` skips selective recompute during search
+
+Storage impact:
+- Storing N embeddings of dimension D with float32 requires approximately N × D × 4 bytes
+- Example: 1,000,000 chunks × 768 dims × 4 bytes ≈ 2.86 GB (plus graph/metadata)
+
+Converting an existing index (rebuild required):
+```bash
+# Rebuild in-place (ensure you still have original docs or can regenerate chunks)
+leann build my-index --force --no-recompute --no-compact
+```
+
+Python API usage:
+```python
+from leann import LeannSearcher
+
+searcher = LeannSearcher("/path/to/my-index.leann")
+results = searcher.search("your query", top_k=10, recompute_embeddings=False)
+```
+
+Trade-offs:
+- Lower latency and fewer network hops at query time
+- Significantly higher storage (10–100× vs selective recomputation)
+- Slightly larger memory footprint during build and search
+
+Quick benchmark results (`benchmarks/benchmark_no_recompute.py` with 5k texts, complexity=32):
+
+- HNSW
+
+  ```text
+  recompute=True:  search_time=0.818s, size=1.1MB
+  recompute=False: search_time=0.012s, size=16.6MB
+  ```
+
+- DiskANN
+
+  ```text
+  recompute=True:  search_time=0.041s, size=5.9MB
+  recompute=False: search_time=0.013s, size=24.6MB
+  ```
+
+Conclusion:
+- **HNSW**: `no-recompute` is significantly faster (no embedding recomputation) but requires much more storage (stores all embeddings)
+- **DiskANN**: `no-recompute` uses PQ + partial real distances during traversal (slower but higher accuracy), while `recompute=True` uses pure PQ traversal + final reranking (faster traversal, enables build-time partitioning for smaller storage)
+
 
-**Disable when**:
-- You have abundant storage and memory
-- Need extremely low latency (< 100ms)
-- Running a read-heavy workload where storage cost is acceptable
 
 ## Further Reading
 
 - [Lessons Learned Developing LEANN](https://yichuan-w.github.io/blog/lessons_learned_in_dev_leann/)
 - [LEANN Technical Paper](https://arxiv.org/abs/2506.08276)
 - [DiskANN Original Paper](https://papers.nips.cc/paper/2019/file/09853c7fb1d3f8ee67a61b6bf4a7f8e6-Paper.pdf)
+- [SSD-based Graph Partitioning](https://github.com/SonglinLife/SSD_BASED_PLAN)

docs/features.md

@@ -3,6 +3,7 @@
 ## 🔥 Core Features
 
 - **🔄 Real-time Embeddings** - Eliminate heavy embedding storage with dynamic computation using optimized ZMQ servers and highly optimized search paradigm (overlapping and batching) with highly optimized embedding engine
+- **🧠 AST-Aware Code Chunking** - Intelligent code chunking that preserves semantic boundaries (functions, classes, methods) for Python, Java, C#, and TypeScript files
 - **📈 Scalable Architecture** - Handles millions of documents on consumer hardware; the larger your dataset, the more LEANN can save
 - **🎯 Graph Pruning** - Advanced techniques to minimize the storage overhead of vector search to a limited footprint
 - **🏗️ Pluggable Backends** - HNSW/FAISS (default), with optional DiskANN for large-scale deployments

docs/grep_search.md

@@ -0,0 +1,149 @@
+# LEANN Grep Search Usage Guide
+
+## Overview
+
+LEANN's grep search functionality provides exact text matching for finding specific code patterns, error messages, function names, or exact phrases in your indexed documents.
+
+## Basic Usage
+
+### Simple Grep Search
+
+```python
+from leann.api import LeannSearcher
+
+searcher = LeannSearcher("your_index_path")
+
+# Exact text search
+results = searcher.search("def authenticate_user", use_grep=True, top_k=5)
+
+for result in results:
+    print(f"Score: {result.score}")
+    print(f"Text: {result.text[:100]}...")
+    print("-" * 40)
+```
+
+### Comparison: Semantic vs Grep Search
+
+```python
+# Semantic search - finds conceptually similar content
+semantic_results = searcher.search("machine learning algorithms", top_k=3)
+
+# Grep search - finds exact text matches
+grep_results = searcher.search("def train_model", use_grep=True, top_k=3)
+```
+
+## When to Use Grep Search
+
+### Use Cases
+
+- **Code Search**: Finding specific function definitions, class names, or variable references
+- **Error Debugging**: Locating exact error messages or stack traces
+- **Documentation**: Finding specific API endpoints or exact terminology
+
+### Examples
+
+```python
+# Find function definitions
+functions = searcher.search("def __init__", use_grep=True)
+
+# Find import statements
+imports = searcher.search("from sklearn import", use_grep=True)
+
+# Find specific error types
+errors = searcher.search("FileNotFoundError", use_grep=True)
+
+# Find TODO comments
+todos = searcher.search("TODO:", use_grep=True)
+
+# Find configuration entries
+configs = searcher.search("server_port=", use_grep=True)
+```
+
+## Technical Details
+
+### How It Works
+
+1. **File Location**: Grep search operates on the raw text stored in `.jsonl` files
+2. **Command Execution**: Uses the system `grep` command with case-insensitive search
+3. **Result Processing**: Parses JSON lines and extracts text and metadata
+4. **Scoring**: Simple frequency-based scoring based on query term occurrences
+
+### Search Process
+
+```
+Query: "def train_model"
+  ↓
+grep -i -n "def train_model" documents.leann.passages.jsonl
+  ↓
+Parse matching JSON lines
+  ↓
+Calculate scores based on term frequency
+  ↓
+Return top_k results
+```
+
+### Scoring Algorithm
+
+```python
+# Term frequency in document
+score = text.lower().count(query.lower())
+```
+
+Results are ranked by score (highest first), with higher scores indicating more occurrences of the search term.
+
+## Error Handling
+
+### Common Issues
+
+#### Grep Command Not Found
+```
+RuntimeError: grep command not found. Please install grep or use semantic search.
+```
+
+**Solution**: Install grep on your system:
+- **Ubuntu/Debian**: `sudo apt-get install grep`
+- **macOS**: grep is pre-installed
+- **Windows**: Use WSL or install grep via Git Bash/MSYS2
+
+#### No Results Found
+```python
+# Check if your query exists in the raw data
+results = searcher.search("your_query", use_grep=True)
+if not results:
+    print("No exact matches found. Try:")
+    print("1. Check spelling and case")
+    print("2. Use partial terms")
+    print("3. Switch to semantic search")
+```
+
+## Complete Example
+
+```python
+#!/usr/bin/env python3
+"""
+Grep Search Example
+Demonstrates grep search for exact text matching.
+"""
+
+from leann.api import LeannSearcher
+
+def demonstrate_grep_search():
+    # Initialize searcher
+    searcher = LeannSearcher("my_index")
+
+    print("=== Function Search ===")
+    functions = searcher.search("def __init__", use_grep=True, top_k=5)
+    for i, result in enumerate(functions, 1):
+        print(f"{i}. Score: {result.score}")
+        print(f"   Preview: {result.text[:60]}...")
+        print()
+
+    print("=== Error Search ===")
+    errors = searcher.search("FileNotFoundError", use_grep=True, top_k=3)
+    for result in errors:
+        print(f"Content: {result.text.strip()}")
+        print("-" * 40)
+
+if __name__ == "__main__":
+    demonstrate_grep_search()
+```

docs/metadata_filtering.md

@@ -0,0 +1,300 @@
+# LEANN Metadata Filtering Usage Guide
+
+## Overview
+
+Leann possesses metadata filtering capabilities that allow you to filter search results based on arbitrary metadata fields set during chunking. This feature enables use cases like spoiler-free book search, document filtering by date/type, code search by file type, and potentially much more.
+
+## Basic Usage
+
+### Adding Metadata to Your Documents
+
+When building your index, add metadata to each text chunk:
+
+```python
+from leann.api import LeannBuilder
+
+builder = LeannBuilder("hnsw")
+
+# Add text with metadata
+builder.add_text(
+    text="Chapter 1: Alice falls down the rabbit hole",
+    metadata={
+        "chapter": 1,
+        "character": "Alice",
+        "themes": ["adventure", "curiosity"],
+        "word_count": 150
+    }
+)
+
+builder.build_index("alice_in_wonderland_index")
+```
+
+### Searching with Metadata Filters
+
+Use the `metadata_filters` parameter in search calls:
+
+```python
+from leann.api import LeannSearcher
+
+searcher = LeannSearcher("alice_in_wonderland_index")
+
+# Search with filters
+results = searcher.search(
+    query="What happens to Alice?",
+    top_k=10,
+    metadata_filters={
+        "chapter": {"<=": 5},           # Only chapters 1-5
+        "spoiler_level": {"!=": "high"} # No high spoilers
+    }
+)
+```
+
+## Filter Syntax
+
+### Basic Structure
+
+```python
+metadata_filters = {
+    "field_name": {"operator": value},
+    "another_field": {"operator": value}
+}
+```
+
+### Supported Operators
+
+#### Comparison Operators
+- `"=="`: Equal to
+- `"!="`: Not equal to
+- `"<"`: Less than
+- `"<="`: Less than or equal
+- `">"`: Greater than
+- `">="`: Greater than or equal
+
+```python
+# Examples
+{"chapter": {"==": 1}}           # Exactly chapter 1
+{"page": {">": 100}}            # Pages after 100
+{"rating": {">=": 4.0}}         # Rating 4.0 or higher
+{"word_count": {"<": 500}}      # Short passages
+```
+
+#### Membership Operators
+- `"in"`: Value is in list
+- `"not_in"`: Value is not in list
+
+```python
+# Examples
+{"character": {"in": ["Alice", "Bob"]}}      # Alice OR Bob
+{"genre": {"not_in": ["horror", "thriller"]}} # Exclude genres
+{"tags": {"in": ["fiction", "adventure"]}}   # Any of these tags
+```
+
+#### String Operators
+- `"contains"`: String contains substring
+- `"starts_with"`: String starts with prefix
+- `"ends_with"`: String ends with suffix
+
+```python
+# Examples
+{"title": {"contains": "alice"}}        # Title contains "alice"
+{"filename": {"ends_with": ".py"}}      # Python files
+{"author": {"starts_with": "Dr."}}      # Authors with "Dr." prefix
+```
+
+#### Boolean Operators
+- `"is_true"`: Field is truthy
+- `"is_false"`: Field is falsy
+
+```python
+# Examples
+{"is_published": {"is_true": True}}     # Published content
+{"is_draft": {"is_false": False}}       # Not drafts
+```
+
+### Multiple Operators on Same Field
+
+You can apply multiple operators to the same field (AND logic):
+
+```python
+metadata_filters = {
+    "word_count": {
+        ">=": 100,    # At least 100 words
+        "<=": 500     # At most 500 words
+    }
+}
+```
+
+### Compound Filters
+
+Multiple fields are combined with AND logic:
+
+```python
+metadata_filters = {
+    "chapter": {"<=": 10},              # Up to chapter 10
+    "character": {"==": "Alice"},       # About Alice
+    "spoiler_level": {"!=": "high"}     # No major spoilers
+}
+```
+
+## Use Case Examples
+
+### 1. Spoiler-Free Book Search
+
+```python
+# Reader has only read up to chapter 5
+def search_spoiler_free(query, max_chapter):
+    return searcher.search(
+        query=query,
+        metadata_filters={
+            "chapter": {"<=": max_chapter},
+            "spoiler_level": {"in": ["none", "low"]}
+        }
+    )
+
+results = search_spoiler_free("What happens to Alice?", max_chapter=5)
+```
+
+### 2. Document Management by Date
+
+```python
+# Find recent documents
+recent_docs = searcher.search(
+    query="project updates",
+    metadata_filters={
+        "date": {">=": "2024-01-01"},
+        "document_type": {"==": "report"}
+    }
+)
+```
+
+### 3. Code Search by File Type
+
+```python
+# Search only Python files
+python_code = searcher.search(
+    query="authentication function",
+    metadata_filters={
+        "file_extension": {"==": ".py"},
+        "lines_of_code": {"<": 100}
+    }
+)
+```
+
+### 4. Content Filtering by Audience
+
+```python
+# Age-appropriate content
+family_content = searcher.search(
+    query="adventure stories",
+    metadata_filters={
+        "age_rating": {"in": ["G", "PG"]},
+        "content_warnings": {"not_in": ["violence", "adult_themes"]}
+    }
+)
+```
+
+### 5. Multi-Book Series Management
+
+```python
+# Search across first 3 books only
+early_series = searcher.search(
+    query="character development",
+    metadata_filters={
+        "series": {"==": "Harry Potter"},
+        "book_number": {"<=": 3}
+    }
+)
+```
+
+## Running the Example
+
+You can see metadata filtering in action with our spoiler-free book RAG example:
+
+```bash
+# Don't forget to set up the environment
+uv venv
+source .venv/bin/activate
+
+# Set your OpenAI API key (required for embeddings, but you can update the example locally and use ollama instead)
+export OPENAI_API_KEY="your-api-key-here"
+
+# Run the spoiler-free book RAG example
+uv run examples/spoiler_free_book_rag.py
+```
+
+This example demonstrates:
+- Building an index with metadata (chapter numbers, characters, themes, locations)
+- Searching with filters to avoid spoilers (e.g., only show results up to chapter 5)
+- Different scenarios for readers at various points in the book
+
+The example uses Alice's Adventures in Wonderland as sample data and shows how you can search for information without revealing plot points from later chapters.
+
+## Advanced Patterns
+
+### Custom Chunking with metadata
+
+```python
+def chunk_book_with_metadata(book_text, book_info):
+    chunks = []
+
+    for chapter_num, chapter_text in parse_chapters(book_text):
+        # Extract entities, themes, etc.
+        characters = extract_characters(chapter_text)
+        themes = classify_themes(chapter_text)
+        spoiler_level = assess_spoiler_level(chapter_text, chapter_num)
+
+        # Create chunks with rich metadata
+        for paragraph in split_paragraphs(chapter_text):
+            chunks.append({
+                "text": paragraph,
+                "metadata": {
+                    "book_title": book_info["title"],
+                    "chapter": chapter_num,
+                    "characters": characters,
+                    "themes": themes,
+                    "spoiler_level": spoiler_level,
+                    "word_count": len(paragraph.split()),
+                    "reading_level": calculate_reading_level(paragraph)
+                }
+            })
+
+    return chunks
+```
+
+## Performance Considerations
+
+### Efficient Filtering Strategies
+
+1. **Post-search filtering**: Applies filters after vector search, which should be efficient for typical result sets (10-100 results).
+
+2. **Metadata design**: Keep metadata fields simple and avoid deeply nested structures.
+
+### Best Practices
+
+1. **Consistent metadata schema**: Use consistent field names and value types across your documents.
+
+2. **Reasonable metadata size**: Keep metadata reasonably sized to avoid storage overhead.
+
+3. **Type consistency**: Use consistent data types for the same fields (e.g., always integers for chapter numbers).
+
+4. **Index multiple granularities**: Consider chunking at different levels (paragraph, section, chapter) with appropriate metadata.
+
+### Adding Metadata to Existing Indices
+
+To add metadata filtering to existing indices, you'll need to rebuild them with metadata:
+
+```python
+# Read existing passages and add metadata
+def add_metadata_to_existing_chunks(chunks):
+    for chunk in chunks:
+        # Extract or assign metadata based on content
+        chunk["metadata"] = extract_metadata(chunk["text"])
+    return chunks
+
+# Rebuild index with metadata
+enhanced_chunks = add_metadata_to_existing_chunks(existing_chunks)
+builder = LeannBuilder("hnsw")
+for chunk in enhanced_chunks:
+    builder.add_text(chunk["text"], chunk["metadata"])
+builder.build_index("enhanced_index")
+```

examples/dynamic_update_no_recompute.py

@@ -0,0 +1,404 @@
+"""Dynamic HNSW update demo without compact storage.
+
+This script reproduces the minimal scenario we used while debugging on-the-fly
+recompute:
+
+1. Build a non-compact HNSW index from the first few paragraphs of a text file.
+2. Print the top results with `recompute_embeddings=True`.
+3. Append additional paragraphs with :meth:`LeannBuilder.update_index`.
+4. Run the same query again to show the newly inserted passages.
+
+Run it with ``uv`` (optionally pointing LEANN_HNSW_LOG_PATH at a file to inspect
+ZMQ activity)::
+
+    LEANN_HNSW_LOG_PATH=embedding_fetch.log \
+    uv run -m examples.dynamic_update_no_recompute \
+      --index-path .leann/examples/leann-demo.leann
+
+By default the script builds an index from ``data/2501.14312v1 (1).pdf`` and
+then updates it with LEANN-related material from ``data/2506.08276v1.pdf``.
+It issues the query "What's LEANN?" before and after the update to show how the
+new passages become immediately searchable. The script uses the
+``sentence-transformers/all-MiniLM-L6-v2`` model with ``is_recompute=True`` so
+Faiss pulls existing vectors on demand via the ZMQ embedding server, while
+freshly added passages are embedded locally just like the initial build.
+
+To make storage comparisons easy, the script can also build a matching
+``is_recompute=False`` baseline (enabled by default) and report the index size
+delta after the update. Disable the baseline run with
+``--skip-compare-no-recompute`` if you only need the recompute flow.
+"""
+
+import argparse
+import json
+from collections.abc import Iterable
+from pathlib import Path
+from typing import Any
+
+from leann.api import LeannBuilder, LeannSearcher
+from leann.registry import register_project_directory
+
+from apps.chunking import create_text_chunks
+
+REPO_ROOT = Path(__file__).resolve().parents[1]
+
+DEFAULT_QUERY = "What's LEANN?"
+DEFAULT_INITIAL_FILES = [REPO_ROOT / "data" / "2501.14312v1 (1).pdf"]
+DEFAULT_UPDATE_FILES = [REPO_ROOT / "data" / "2506.08276v1.pdf"]
+
+
+def load_chunks_from_files(paths: list[Path]) -> list[str]:
+    from llama_index.core import SimpleDirectoryReader
+
+    documents = []
+    for path in paths:
+        p = path.expanduser().resolve()
+        if not p.exists():
+            raise FileNotFoundError(f"Input path not found: {p}")
+        if p.is_dir():
+            reader = SimpleDirectoryReader(str(p), recursive=False)
+            documents.extend(reader.load_data(show_progress=True))
+        else:
+            reader = SimpleDirectoryReader(input_files=[str(p)])
+            documents.extend(reader.load_data(show_progress=True))
+
+    if not documents:
+        return []
+
+    chunks = create_text_chunks(
+        documents,
+        chunk_size=512,
+        chunk_overlap=128,
+        use_ast_chunking=False,
+    )
+    return [c for c in chunks if isinstance(c, str) and c.strip()]
+
+
+def run_search(index_path: Path, query: str, top_k: int, *, recompute_embeddings: bool) -> list:
+    searcher = LeannSearcher(str(index_path))
+    try:
+        return searcher.search(
+            query=query,
+            top_k=top_k,
+            recompute_embeddings=recompute_embeddings,
+            batch_size=16,
+        )
+    finally:
+        searcher.cleanup()
+
+
+def print_results(title: str, results: Iterable) -> None:
+    print(f"\n=== {title} ===")
+    res_list = list(results)
+    print(f"results count: {len(res_list)}")
+    print("passages:")
+    if not res_list:
+        print("  (no passages returned)")
+    for res in res_list:
+        snippet = res.text.replace("\n", " ")[:120]
+        print(f"  - {res.id}: {snippet}... (score={res.score:.4f})")
+
+
+def build_initial_index(
+    index_path: Path,
+    paragraphs: list[str],
+    model_name: str,
+    embedding_mode: str,
+    is_recompute: bool,
+) -> None:
+    builder = LeannBuilder(
+        backend_name="hnsw",
+        embedding_model=model_name,
+        embedding_mode=embedding_mode,
+        is_compact=False,
+        is_recompute=is_recompute,
+    )
+    for idx, passage in enumerate(paragraphs):
+        builder.add_text(passage, metadata={"id": str(idx)})
+    builder.build_index(str(index_path))
+
+
+def update_index(
+    index_path: Path,
+    start_id: int,
+    paragraphs: list[str],
+    model_name: str,
+    embedding_mode: str,
+    is_recompute: bool,
+) -> None:
+    updater = LeannBuilder(
+        backend_name="hnsw",
+        embedding_model=model_name,
+        embedding_mode=embedding_mode,
+        is_compact=False,
+        is_recompute=is_recompute,
+    )
+    for offset, passage in enumerate(paragraphs, start=start_id):
+        updater.add_text(passage, metadata={"id": str(offset)})
+    updater.update_index(str(index_path))
+
+
+def ensure_index_dir(index_path: Path) -> None:
+    index_path.parent.mkdir(parents=True, exist_ok=True)
+
+
+def cleanup_index_files(index_path: Path) -> None:
+    """Remove leftover index artifacts for a clean rebuild."""
+
+    parent = index_path.parent
+    if not parent.exists():
+        return
+    stem = index_path.stem
+    for file in parent.glob(f"{stem}*"):
+        if file.is_file():
+            file.unlink()
+
+
+def index_file_size(index_path: Path) -> int:
+    """Return the size of the primary .index file for the given index path."""
+
+    index_file = index_path.parent / f"{index_path.stem}.index"
+    return index_file.stat().st_size if index_file.exists() else 0
+
+
+def load_metadata_snapshot(index_path: Path) -> dict[str, Any] | None:
+    meta_path = index_path.parent / f"{index_path.name}.meta.json"
+    if not meta_path.exists():
+        return None
+    try:
+        return json.loads(meta_path.read_text())
+    except json.JSONDecodeError:
+        return None
+
+
+def run_workflow(
+    *,
+    label: str,
+    index_path: Path,
+    initial_paragraphs: list[str],
+    update_paragraphs: list[str],
+    model_name: str,
+    embedding_mode: str,
+    is_recompute: bool,
+    query: str,
+    top_k: int,
+) -> dict[str, Any]:
+    prefix = f"[{label}] " if label else ""
+
+    ensure_index_dir(index_path)
+    cleanup_index_files(index_path)
+
+    print(f"{prefix}Building initial index...")
+    build_initial_index(
+        index_path,
+        initial_paragraphs,
+        model_name,
+        embedding_mode,
+        is_recompute=is_recompute,
+    )
+
+    initial_size = index_file_size(index_path)
+    before_results = run_search(
+        index_path,
+        query,
+        top_k,
+        recompute_embeddings=is_recompute,
+    )
+
+    print(f"\n{prefix}Updating index with additional passages...")
+    update_index(
+        index_path,
+        start_id=len(initial_paragraphs),
+        paragraphs=update_paragraphs,
+        model_name=model_name,
+        embedding_mode=embedding_mode,
+        is_recompute=is_recompute,
+    )
+
+    after_results = run_search(
+        index_path,
+        query,
+        top_k,
+        recompute_embeddings=is_recompute,
+    )
+    updated_size = index_file_size(index_path)
+
+    return {
+        "initial_size": initial_size,
+        "updated_size": updated_size,
+        "delta": updated_size - initial_size,
+        "before_results": before_results,
+        "after_results": after_results,
+        "metadata": load_metadata_snapshot(index_path),
+    }
+
+
+def main() -> None:
+    parser = argparse.ArgumentParser(description=__doc__)
+    parser.add_argument(
+        "--initial-files",
+        type=Path,
+        nargs="+",
+        default=DEFAULT_INITIAL_FILES,
+        help="Initial document files (PDF/TXT) used to build the base index",
+    )
+    parser.add_argument(
+        "--index-path",
+        type=Path,
+        default=Path(".leann/examples/leann-demo.leann"),
+        help="Destination index path (default: .leann/examples/leann-demo.leann)",
+    )
+    parser.add_argument(
+        "--initial-count",
+        type=int,
+        default=8,
+        help="Number of chunks to use from the initial documents (default: 8)",
+    )
+    parser.add_argument(
+        "--update-files",
+        type=Path,
+        nargs="*",
+        default=DEFAULT_UPDATE_FILES,
+        help="Additional documents to add during update (PDF/TXT)",
+    )
+    parser.add_argument(
+        "--update-count",
+        type=int,
+        default=4,
+        help="Number of chunks to append from update documents (default: 4)",
+    )
+    parser.add_argument(
+        "--update-text",
+        type=str,
+        default=(
+            "LEANN (Lightweight Embedding ANN) is an indexing toolkit focused on "
+            "recompute-aware HNSW graphs, allowing embeddings to be regenerated "
+            "on demand to keep disk usage minimal."
+        ),
+        help="Fallback text to append if --update-files is omitted",
+    )
+    parser.add_argument(
+        "--top-k",
+        type=int,
+        default=4,
+        help="Number of results to show for each search (default: 4)",
+    )
+    parser.add_argument(
+        "--query",
+        type=str,
+        default=DEFAULT_QUERY,
+        help="Query to run before/after the update",
+    )
+    parser.add_argument(
+        "--embedding-model",
+        type=str,
+        default="sentence-transformers/all-MiniLM-L6-v2",
+        help="Embedding model name",
+    )
+    parser.add_argument(
+        "--embedding-mode",
+        type=str,
+        default="sentence-transformers",
+        choices=["sentence-transformers", "openai", "mlx", "ollama"],
+        help="Embedding backend mode",
+    )
+    parser.add_argument(
+        "--compare-no-recompute",
+        dest="compare_no_recompute",
+        action="store_true",
+        help="Also run a baseline with is_recompute=False and report its index growth.",
+    )
+    parser.add_argument(
+        "--skip-compare-no-recompute",
+        dest="compare_no_recompute",
+        action="store_false",
+        help="Skip building the no-recompute baseline.",
+    )
+    parser.set_defaults(compare_no_recompute=True)
+    args = parser.parse_args()
+
+    ensure_index_dir(args.index_path)
+    register_project_directory(REPO_ROOT)
+
+    initial_chunks = load_chunks_from_files(list(args.initial_files))
+    if not initial_chunks:
+        raise ValueError("No text chunks extracted from the initial files.")
+
+    initial = initial_chunks[: args.initial_count]
+    if not initial:
+        raise ValueError("Initial chunk set is empty after applying --initial-count.")
+
+    if args.update_files:
+        update_chunks = load_chunks_from_files(list(args.update_files))
+        if not update_chunks:
+            raise ValueError("No text chunks extracted from the update files.")
+        to_add = update_chunks[: args.update_count]
+    else:
+        if not args.update_text:
+            raise ValueError("Provide --update-files or --update-text for the update step.")
+        to_add = [args.update_text]
+    if not to_add:
+        raise ValueError("Update chunk set is empty after applying --update-count.")
+
+    recompute_stats = run_workflow(
+        label="recompute",
+        index_path=args.index_path,
+        initial_paragraphs=initial,
+        update_paragraphs=to_add,
+        model_name=args.embedding_model,
+        embedding_mode=args.embedding_mode,
+        is_recompute=True,
+        query=args.query,
+        top_k=args.top_k,
+    )
+
+    print_results("initial search", recompute_stats["before_results"])
+    print_results("after update", recompute_stats["after_results"])
+    print(
+        f"\n[recompute] Index file size change: {recompute_stats['initial_size']} -> {recompute_stats['updated_size']} bytes"
+        f" (Δ {recompute_stats['delta']})"
+    )
+
+    if recompute_stats["metadata"]:
+        meta_view = {k: recompute_stats["metadata"].get(k) for k in ("is_compact", "is_pruned")}
+        print("[recompute] metadata snapshot:")
+        print(json.dumps(meta_view, indent=2))
+
+    if args.compare_no_recompute:
+        baseline_path = (
+            args.index_path.parent / f"{args.index_path.stem}-norecompute{args.index_path.suffix}"
+        )
+        baseline_stats = run_workflow(
+            label="no-recompute",
+            index_path=baseline_path,
+            initial_paragraphs=initial,
+            update_paragraphs=to_add,
+            model_name=args.embedding_model,
+            embedding_mode=args.embedding_mode,
+            is_recompute=False,
+            query=args.query,
+            top_k=args.top_k,
+        )
+
+        print(
+            f"\n[no-recompute] Index file size change: {baseline_stats['initial_size']} -> {baseline_stats['updated_size']} bytes"
+            f" (Δ {baseline_stats['delta']})"
+        )
+
+        after_texts = [res.text for res in recompute_stats["after_results"]]
+        baseline_after_texts = [res.text for res in baseline_stats["after_results"]]
+        if after_texts == baseline_after_texts:
+            print(
+                "[no-recompute] Search results match recompute baseline; see above for the shared output."
+            )
+        else:
+            print("[no-recompute] WARNING: search results differ from recompute baseline.")
+
+        if baseline_stats["metadata"]:
+            meta_view = {k: baseline_stats["metadata"].get(k) for k in ("is_compact", "is_pruned")}
+            print("[no-recompute] metadata snapshot:")
+            print(json.dumps(meta_view, indent=2))
+
+
+if __name__ == "__main__":
+    main()

examples/grep_search_example.py

@@ -0,0 +1,35 @@
+"""
+Grep Search Example
+
+Shows how to use grep-based text search instead of semantic search.
+Useful when you need exact text matches rather than meaning-based results.
+"""
+
+from leann import LeannSearcher
+
+# Load your index
+searcher = LeannSearcher("my-documents.leann")
+
+# Regular semantic search
+print("=== Semantic Search ===")
+results = searcher.search("machine learning algorithms", top_k=3)
+for result in results:
+    print(f"Score: {result.score:.3f}")
+    print(f"Text: {result.text[:80]}...")
+    print()
+
+# Grep-based search for exact text matches
+print("=== Grep Search ===")
+results = searcher.search("def train_model", top_k=3, use_grep=True)
+for result in results:
+    print(f"Score: {result.score}")
+    print(f"Text: {result.text[:80]}...")
+    print()
+
+# Find specific error messages
+error_results = searcher.search("FileNotFoundError", use_grep=True)
+print(f"Found {len(error_results)} files mentioning FileNotFoundError")
+
+# Search for function definitions
+func_results = searcher.search("class SearchResult", use_grep=True, top_k=5)
+print(f"Found {len(func_results)} class definitions")

examples/mcp_integration_demo.py

@@ -0,0 +1,181 @@
+#!/usr/bin/env python3
+"""
+MCP Integration Examples for LEANN
+
+This script demonstrates how to use LEANN with different MCP servers for
+RAG on various platforms like Slack and Twitter.
+
+Examples:
+1. Slack message RAG via MCP
+2. Twitter bookmark RAG via MCP
+3. Testing MCP server connections
+"""
+
+import asyncio
+import sys
+from pathlib import Path
+
+# Add the parent directory to the path so we can import from apps
+sys.path.append(str(Path(__file__).parent.parent))
+
+from apps.slack_rag import SlackMCPRAG
+from apps.twitter_rag import TwitterMCPRAG
+
+
+async def demo_slack_mcp():
+    """Demonstrate Slack MCP integration."""
+    print("=" * 60)
+    print("🔥 Slack MCP RAG Demo")
+    print("=" * 60)
+    
+    print("\n1. Testing Slack MCP server connection...")
+    
+    # This would typically use a real MCP server command
+    # For demo purposes, we show what the command would look like
+    slack_app = SlackMCPRAG()
+    
+    # Simulate command line arguments for testing
+    class MockArgs:
+        mcp_server = "slack-mcp-server"  # This would be the actual MCP server command
+        workspace_name = "my-workspace"
+        channels = ["general", "random", "dev-team"]
+        no_concatenate_conversations = False
+        max_messages_per_channel = 50
+        test_connection = True
+        
+    print(f"MCP Server Command: {MockArgs.mcp_server}")
+    print(f"Workspace: {MockArgs.workspace_name}")
+    print(f"Channels: {', '.join(MockArgs.channels)}")
+    
+    # In a real scenario, you would run:
+    # success = await slack_app.test_mcp_connection(MockArgs)
+    
+    print("\n📝 Example usage:")
+    print("python -m apps.slack_rag \\")
+    print("  --mcp-server 'slack-mcp-server' \\")
+    print("  --workspace-name 'my-team' \\")
+    print("  --channels general dev-team \\")
+    print("  --test-connection")
+    
+    print("\n🔍 After indexing, you could query:")
+    print("- 'What did the team discuss about the project deadline?'")
+    print("- 'Find messages about the new feature launch'")
+    print("- 'Show me conversations about budget planning'")
+
+
+async def demo_twitter_mcp():
+    """Demonstrate Twitter MCP integration."""
+    print("\n" + "=" * 60)
+    print("🐦 Twitter MCP RAG Demo")
+    print("=" * 60)
+    
+    print("\n1. Testing Twitter MCP server connection...")
+    
+    twitter_app = TwitterMCPRAG()
+    
+    class MockArgs:
+        mcp_server = "twitter-mcp-server"
+        username = None  # Fetch all bookmarks
+        max_bookmarks = 500
+        no_tweet_content = False
+        no_metadata = False
+        test_connection = True
+        
+    print(f"MCP Server Command: {MockArgs.mcp_server}")
+    print(f"Max Bookmarks: {MockArgs.max_bookmarks}")
+    print(f"Include Content: {not MockArgs.no_tweet_content}")
+    print(f"Include Metadata: {not MockArgs.no_metadata}")
+    
+    print("\n📝 Example usage:")
+    print("python -m apps.twitter_rag \\")
+    print("  --mcp-server 'twitter-mcp-server' \\")
+    print("  --max-bookmarks 1000 \\")
+    print("  --test-connection")
+    
+    print("\n🔍 After indexing, you could query:")
+    print("- 'What AI articles did I bookmark last month?'")
+    print("- 'Find tweets about machine learning techniques'")
+    print("- 'Show me bookmarked threads about startup advice'")
+
+
+async def show_mcp_server_setup():
+    """Show how to set up MCP servers."""
+    print("\n" + "=" * 60)
+    print("⚙️  MCP Server Setup Guide")
+    print("=" * 60)
+    
+    print("\n🔧 Setting up Slack MCP Server:")
+    print("1. Install a Slack MCP server (example commands):")
+    print("   npm install -g slack-mcp-server")
+    print("   # OR")
+    print("   pip install slack-mcp-server")
+    
+    print("\n2. Configure Slack credentials:")
+    print("   export SLACK_BOT_TOKEN='xoxb-your-bot-token'")
+    print("   export SLACK_APP_TOKEN='xapp-your-app-token'")
+    
+    print("\n3. Test the server:")
+    print("   slack-mcp-server --help")
+    
+    print("\n🔧 Setting up Twitter MCP Server:")
+    print("1. Install a Twitter MCP server:")
+    print("   npm install -g twitter-mcp-server")
+    print("   # OR")
+    print("   pip install twitter-mcp-server")
+    
+    print("\n2. Configure Twitter API credentials:")
+    print("   export TWITTER_API_KEY='your-api-key'")
+    print("   export TWITTER_API_SECRET='your-api-secret'")
+    print("   export TWITTER_ACCESS_TOKEN='your-access-token'")
+    print("   export TWITTER_ACCESS_TOKEN_SECRET='your-access-token-secret'")
+    
+    print("\n3. Test the server:")
+    print("   twitter-mcp-server --help")
+
+
+async def show_integration_benefits():
+    """Show the benefits of MCP integration."""
+    print("\n" + "=" * 60)
+    print("🌟 Benefits of MCP Integration")
+    print("=" * 60)
+    
+    benefits = [
+        ("🔄 Live Data Access", "Fetch real-time data from platforms without manual exports"),
+        ("🔌 Standardized Protocol", "Use any MCP-compatible server with minimal code changes"),
+        ("🚀 Easy Extension", "Add new platforms by implementing MCP readers"),
+        ("🔒 Secure Access", "MCP servers handle authentication and API management"),
+        ("📊 Rich Metadata", "Access full platform metadata (timestamps, engagement, etc.)"),
+        ("⚡ Efficient Processing", "Stream data directly into LEANN without intermediate files"),
+    ]
+    
+    for title, description in benefits:
+        print(f"\n{title}")
+        print(f"   {description}")
+
+
+async def main():
+    """Main demo function."""
+    print("🎯 LEANN MCP Integration Examples")
+    print("This demo shows how to integrate LEANN with MCP servers for various platforms.")
+    
+    await demo_slack_mcp()
+    await demo_twitter_mcp()
+    await show_mcp_server_setup()
+    await show_integration_benefits()
+    
+    print("\n" + "=" * 60)
+    print("✨ Next Steps")
+    print("=" * 60)
+    print("1. Install and configure MCP servers for your platforms")
+    print("2. Test connections using --test-connection flag")
+    print("3. Run indexing to build your RAG knowledge base")
+    print("4. Start querying your personal data!")
+    
+    print("\n📚 For more information:")
+    print("- Check the README for detailed setup instructions")
+    print("- Look at the apps/slack_rag.py and apps/twitter_rag.py for implementation details")
+    print("- Explore other MCP servers for additional platforms")
+
+
+if __name__ == "__main__":
+    asyncio.run(main())

examples/spoiler_free_book_rag.py

@@ -0,0 +1,250 @@
+#!/usr/bin/env python3
+"""
+Spoiler-Free Book RAG Example using LEANN Metadata Filtering
+
+This example demonstrates how to use LEANN's metadata filtering to create
+a spoiler-free book RAG system where users can search for information
+up to a specific chapter they've read.
+
+Usage:
+    python spoiler_free_book_rag.py
+"""
+
+import os
+import sys
+from typing import Any, Optional
+
+# Add LEANN to path (adjust path as needed)
+sys.path.insert(0, os.path.join(os.path.dirname(__file__), "../packages/leann-core/src"))
+
+from leann.api import LeannBuilder, LeannSearcher
+
+
+def chunk_book_with_metadata(book_title: str = "Sample Book") -> list[dict[str, Any]]:
+    """
+    Create sample book chunks with metadata for demonstration.
+
+    In a real implementation, this would parse actual book files (epub, txt, etc.)
+    and extract chapter boundaries, character mentions, etc.
+
+    Args:
+        book_title: Title of the book
+
+    Returns:
+        List of chunk dictionaries with text and metadata
+    """
+    # Sample book chunks with metadata
+    # In practice, you'd use proper text processing libraries
+
+    sample_chunks = [
+        {
+            "text": "Alice was beginning to get very tired of sitting by her sister on the bank, and of having nothing to do.",
+            "metadata": {
+                "book": book_title,
+                "chapter": 1,
+                "page": 1,
+                "characters": ["Alice", "Sister"],
+                "themes": ["boredom", "curiosity"],
+                "location": "riverbank",
+            },
+        },
+        {
+            "text": "So she was considering in her own mind (as well as she could, for the hot day made her feel very sleepy and stupid), whether the pleasure of making a daisy-chain would be worth the trouble of getting up and picking the daisies, when suddenly a White Rabbit with pink eyes ran close by her.",
+            "metadata": {
+                "book": book_title,
+                "chapter": 1,
+                "page": 2,
+                "characters": ["Alice", "White Rabbit"],
+                "themes": ["decision", "surprise", "magic"],
+                "location": "riverbank",
+            },
+        },
+        {
+            "text": "Alice found herself falling down a very deep well. Either the well was very deep, or she fell very slowly, for she had plenty of time as she fell to look about her and to wonder what was going to happen next.",
+            "metadata": {
+                "book": book_title,
+                "chapter": 2,
+                "page": 15,
+                "characters": ["Alice"],
+                "themes": ["falling", "wonder", "transformation"],
+                "location": "rabbit hole",
+            },
+        },
+        {
+            "text": "Alice meets the Cheshire Cat, who tells her that everyone in Wonderland is mad, including Alice herself.",
+            "metadata": {
+                "book": book_title,
+                "chapter": 6,
+                "page": 85,
+                "characters": ["Alice", "Cheshire Cat"],
+                "themes": ["madness", "philosophy", "identity"],
+                "location": "Duchess's house",
+            },
+        },
+        {
+            "text": "At the Queen's croquet ground, Alice witnesses the absurd trial that reveals the arbitrary nature of Wonderland's justice system.",
+            "metadata": {
+                "book": book_title,
+                "chapter": 8,
+                "page": 120,
+                "characters": ["Alice", "Queen of Hearts", "King of Hearts"],
+                "themes": ["justice", "absurdity", "authority"],
+                "location": "Queen's court",
+            },
+        },
+        {
+            "text": "Alice realizes that Wonderland was all a dream, even the Rabbit, as she wakes up on the riverbank next to her sister.",
+            "metadata": {
+                "book": book_title,
+                "chapter": 12,
+                "page": 180,
+                "characters": ["Alice", "Sister", "Rabbit"],
+                "themes": ["revelation", "reality", "growth"],
+                "location": "riverbank",
+            },
+        },
+    ]
+
+    return sample_chunks
+
+
+def build_spoiler_free_index(book_chunks: list[dict[str, Any]], index_name: str) -> str:
+    """
+    Build a LEANN index with book chunks that include spoiler metadata.
+
+    Args:
+        book_chunks: List of book chunks with metadata
+        index_name: Name for the index
+
+    Returns:
+        Path to the built index
+    """
+    print(f"📚 Building spoiler-free book index: {index_name}")
+
+    # Initialize LEANN builder
+    builder = LeannBuilder(
+        backend_name="hnsw", embedding_model="text-embedding-3-small", embedding_mode="openai"
+    )
+
+    # Add each chunk with its metadata
+    for chunk in book_chunks:
+        builder.add_text(text=chunk["text"], metadata=chunk["metadata"])
+
+    # Build the index
+    index_path = f"{index_name}_book_index"
+    builder.build_index(index_path)
+
+    print(f"✅ Index built successfully: {index_path}")
+    return index_path
+
+
+def spoiler_free_search(
+    index_path: str,
+    query: str,
+    max_chapter: int,
+    character_filter: Optional[list[str]] = None,
+) -> list[dict[str, Any]]:
+    """
+    Perform a spoiler-free search on the book index.
+
+    Args:
+        index_path: Path to the LEANN index
+        query: Search query
+        max_chapter: Maximum chapter number to include
+        character_filter: Optional list of characters to focus on
+
+    Returns:
+        List of search results safe for the reader
+    """
+    print(f"🔍 Searching: '{query}' (up to chapter {max_chapter})")
+
+    searcher = LeannSearcher(index_path)
+
+    metadata_filters = {"chapter": {"<=": max_chapter}}
+
+    if character_filter:
+        metadata_filters["characters"] = {"contains": character_filter[0]}
+
+    results = searcher.search(query=query, top_k=10, metadata_filters=metadata_filters)
+
+    return results
+
+
+def demo_spoiler_free_rag():
+    """
+    Demonstrate the spoiler-free book RAG system.
+    """
+    print("🎭 Spoiler-Free Book RAG Demo")
+    print("=" * 40)
+
+    # Step 1: Prepare book data
+    book_title = "Alice's Adventures in Wonderland"
+    book_chunks = chunk_book_with_metadata(book_title)
+
+    print(f"📖 Loaded {len(book_chunks)} chunks from '{book_title}'")
+
+    # Step 2: Build the index (in practice, this would be done once)
+    try:
+        index_path = build_spoiler_free_index(book_chunks, "alice_wonderland")
+    except Exception as e:
+        print(f"❌ Failed to build index (likely missing dependencies): {e}")
+        print(
+            "💡 This demo shows the filtering logic - actual indexing requires LEANN dependencies"
+        )
+        return
+
+    # Step 3: Demonstrate various spoiler-free searches
+    search_scenarios = [
+        {
+            "description": "Reader who has only read Chapter 1",
+            "query": "What can you tell me about the rabbit?",
+            "max_chapter": 1,
+        },
+        {
+            "description": "Reader who has read up to Chapter 5",
+            "query": "Tell me about Alice's adventures",
+            "max_chapter": 5,
+        },
+        {
+            "description": "Reader who has read most of the book",
+            "query": "What does the Cheshire Cat represent?",
+            "max_chapter": 10,
+        },
+        {
+            "description": "Reader who has read the whole book",
+            "query": "What can you tell me about the rabbit?",
+            "max_chapter": 12,
+        },
+    ]
+
+    for scenario in search_scenarios:
+        print(f"\n📚 Scenario: {scenario['description']}")
+        print(f"   Query: {scenario['query']}")
+
+        try:
+            results = spoiler_free_search(
+                index_path=index_path,
+                query=scenario["query"],
+                max_chapter=scenario["max_chapter"],
+            )
+
+            print(f"   📄 Found {len(results)} results:")
+            for i, result in enumerate(results[:3], 1):  # Show top 3
+                chapter = result.metadata.get("chapter", "?")
+                location = result.metadata.get("location", "?")
+                print(f"      {i}. Chapter {chapter} ({location}): {result.text[:80]}...")
+
+        except Exception as e:
+            print(f"   ❌ Search failed: {e}")
+
+
+if __name__ == "__main__":
+    print("📚 LEANN Spoiler-Free Book RAG Example")
+    print("=====================================")
+
+    try:
+        demo_spoiler_free_rag()
+    except ImportError as e:
+        print(f"❌ Cannot run demo due to missing dependencies: {e}")
+    except Exception as e:
+        print(f"❌ Error running demo: {e}")

llms.txt

@@ -0,0 +1,28 @@
+# llms.txt — LEANN MCP and Agent Integration
+product: LEANN
+homepage: https://github.com/yichuan-w/LEANN
+contact: https://github.com/yichuan-w/LEANN/issues
+
+# Installation
+install: uv tool install leann-core --with leann
+
+# MCP Server Entry Point
+mcp.server: leann_mcp
+mcp.protocol_version: 2024-11-05
+
+# Tools
+mcp.tools: leann_list, leann_search
+
+mcp.tool.leann_list.description: List available LEANN indexes
+mcp.tool.leann_list.input: {}
+
+mcp.tool.leann_search.description: Semantic search across a named LEANN index
+mcp.tool.leann_search.input.index_name: string, required
+mcp.tool.leann_search.input.query: string, required
+mcp.tool.leann_search.input.top_k: integer, optional, default=5, min=1, max=20
+mcp.tool.leann_search.input.complexity: integer, optional, default=32, min=16, max=128
+
+# Notes
+note: Build indexes with `leann build <name> --docs <files...>` before searching.
+example.add: claude mcp add --scope user leann-server -- leann_mcp
+example.verify: claude mcp list | cat

packages/leann-backend-diskann/CMakeLists.txt

@@ -1,8 +0,0 @@
-# packages/leann-backend-diskann/CMakeLists.txt (simplified version)
-
-cmake_minimum_required(VERSION 3.20)
-project(leann_backend_diskann_wrapper)
-
-# Tell CMake to directly enter the DiskANN submodule and execute its own CMakeLists.txt
-# DiskANN will handle everything itself, including compiling Python bindings
-add_subdirectory(src/third_party/DiskANN)

packages/leann-backend-diskann/leann_backend_diskann/__init__.py

@@ -1 +1,7 @@
 from . import diskann_backend as diskann_backend
+from . import graph_partition
+
+# Export main classes and functions
+from .graph_partition import GraphPartitioner, partition_graph
+
+__all__ = ["GraphPartitioner", "diskann_backend", "graph_partition", "partition_graph"]

packages/leann-backend-diskann/leann_backend_diskann/diskann_backend.py

@@ -4,7 +4,7 @@ import os
 import struct
 import sys
 from pathlib import Path
-from typing import Any, Literal
+from typing import Any, Literal, Optional
 
 import numpy as np
 import psutil
@@ -22,6 +22,11 @@ logger = logging.getLogger(__name__)
 @contextlib.contextmanager
 def suppress_cpp_output_if_needed():
     """Suppress C++ stdout/stderr based on LEANN_LOG_LEVEL"""
+    # In CI we avoid fiddling with low-level file descriptors to prevent aborts
+    if os.getenv("CI") == "true":
+        yield
+        return
+
     log_level = os.getenv("LEANN_LOG_LEVEL", "WARNING").upper()
 
     # Only suppress if log level is WARNING or higher (ERROR, CRITICAL)
@@ -137,6 +142,71 @@ class DiskannBuilder(LeannBackendBuilderInterface):
     def __init__(self, **kwargs):
         self.build_params = kwargs
 
+    def _safe_cleanup_after_partition(self, index_dir: Path, index_prefix: str):
+        """
+        Safely cleanup files after partition.
+        In partition mode, C++ doesn't read _disk.index content,
+        so we can delete it if all derived files exist.
+        """
+        disk_index_file = index_dir / f"{index_prefix}_disk.index"
+        beam_search_file = index_dir / f"{index_prefix}_disk_beam_search.index"
+
+        # Required files that C++ partition mode needs
+        # Note: C++ generates these with _disk.index suffix
+        disk_suffix = "_disk.index"
+        required_files = [
+            f"{index_prefix}{disk_suffix}_medoids.bin",  # Critical: assert fails if missing
+            # Note: _centroids.bin is not created in single-shot build - C++ handles this automatically
+            f"{index_prefix}_pq_pivots.bin",  # PQ table
+            f"{index_prefix}_pq_compressed.bin",  # PQ compressed vectors
+        ]
+
+        # Check if all required files exist
+        missing_files = []
+        for filename in required_files:
+            file_path = index_dir / filename
+            if not file_path.exists():
+                missing_files.append(filename)
+
+        if missing_files:
+            logger.warning(
+                f"Cannot safely delete _disk.index - missing required files: {missing_files}"
+            )
+            logger.info("Keeping all original files for safety")
+            return
+
+        # Calculate space savings
+        space_saved = 0
+        files_to_delete = []
+
+        if disk_index_file.exists():
+            space_saved += disk_index_file.stat().st_size
+            files_to_delete.append(disk_index_file)
+
+        if beam_search_file.exists():
+            space_saved += beam_search_file.stat().st_size
+            files_to_delete.append(beam_search_file)
+
+        # Safe to delete!
+        for file_to_delete in files_to_delete:
+            try:
+                os.remove(file_to_delete)
+                logger.info(f"✅ Safely deleted: {file_to_delete.name}")
+            except Exception as e:
+                logger.warning(f"Failed to delete {file_to_delete.name}: {e}")
+
+        if space_saved > 0:
+            space_saved_mb = space_saved / (1024 * 1024)
+            logger.info(f"💾 Space saved: {space_saved_mb:.1f} MB")
+
+            # Show what files are kept
+            logger.info("📁 Kept essential files for partition mode:")
+            for filename in required_files:
+                file_path = index_dir / filename
+                if file_path.exists():
+                    size_mb = file_path.stat().st_size / (1024 * 1024)
+                    logger.info(f"  - {filename} ({size_mb:.1f} MB)")
+
     def build(self, data: np.ndarray, ids: list[str], index_path: str, **kwargs):
         path = Path(index_path)
         index_dir = path.parent
@@ -151,6 +221,17 @@ class DiskannBuilder(LeannBackendBuilderInterface):
         _write_vectors_to_bin(data, index_dir / data_filename)
 
         build_kwargs = {**self.build_params, **kwargs}
+
+        # Extract is_recompute from nested backend_kwargs if needed
+        is_recompute = build_kwargs.get("is_recompute", False)
+        if not is_recompute and "backend_kwargs" in build_kwargs:
+            is_recompute = build_kwargs["backend_kwargs"].get("is_recompute", False)
+
+        # Flatten all backend_kwargs parameters to top level for compatibility
+        if "backend_kwargs" in build_kwargs:
+            nested_params = build_kwargs.pop("backend_kwargs")
+            build_kwargs.update(nested_params)
+
         metric_enum = _get_diskann_metrics().get(
             build_kwargs.get("distance_metric", "mips").lower()
         )
@@ -185,6 +266,30 @@ class DiskannBuilder(LeannBackendBuilderInterface):
                     build_kwargs.get("pq_disk_bytes", 0),
                     "",
                 )
+
+            # Auto-partition if is_recompute is enabled
+            if build_kwargs.get("is_recompute", False):
+                logger.info("is_recompute=True, starting automatic graph partitioning...")
+                from .graph_partition import partition_graph
+
+                # Partition the index using absolute paths
+                # Convert to absolute paths to avoid issues with working directory changes
+                absolute_index_dir = Path(index_dir).resolve()
+                absolute_index_prefix_path = str(absolute_index_dir / index_prefix)
+                disk_graph_path, partition_bin_path = partition_graph(
+                    index_prefix_path=absolute_index_prefix_path,
+                    output_dir=str(absolute_index_dir),
+                    partition_prefix=index_prefix,
+                )
+
+                # Safe cleanup: In partition mode, C++ doesn't read _disk.index content
+                # but still needs the derived files (_medoids.bin, _centroids.bin, etc.)
+                self._safe_cleanup_after_partition(index_dir, index_prefix)
+
+                logger.info("✅ Graph partitioning completed successfully!")
+                logger.info(f"  - Disk graph: {disk_graph_path}")
+                logger.info(f"  - Partition file: {partition_bin_path}")
+
         finally:
             temp_data_file = index_dir / data_filename
             if temp_data_file.exists():
@@ -213,7 +318,26 @@ class DiskannSearcher(BaseSearcher):
 
             # For DiskANN, we need to reinitialize the index when zmq_port changes
             # Store the initialization parameters for later use
-            full_index_prefix = str(self.index_dir / self.index_path.stem)
+            # Note: C++ load method expects the BASE path (without _disk.index suffix)
+            # C++ internally constructs: index_prefix + "_disk.index"
+            index_name = self.index_path.stem  # "simple_test.leann" -> "simple_test"
+            diskann_index_prefix = str(self.index_dir / index_name)  # /path/to/simple_test
+            full_index_prefix = diskann_index_prefix  # /path/to/simple_test (base path)
+
+            # Auto-detect partition files and set partition_prefix
+            partition_graph_file = self.index_dir / f"{index_name}_disk_graph.index"
+            partition_bin_file = self.index_dir / f"{index_name}_partition.bin"
+
+            partition_prefix = ""
+            if partition_graph_file.exists() and partition_bin_file.exists():
+                # C++ expects full path prefix, not just filename
+                partition_prefix = str(self.index_dir / index_name)  # /path/to/simple_test
+                logger.info(
+                    f"✅ Detected partition files, using partition_prefix='{partition_prefix}'"
+                )
+            else:
+                logger.debug("No partition files detected, using standard index files")
+
             self._init_params = {
                 "metric_enum": metric_enum,
                 "full_index_prefix": full_index_prefix,
@@ -221,8 +345,14 @@ class DiskannSearcher(BaseSearcher):
                 "num_nodes_to_cache": kwargs.get("num_nodes_to_cache", 0),
                 "cache_mechanism": 1,
                 "pq_prefix": "",
-                "partition_prefix": "",
+                "partition_prefix": partition_prefix,
             }
+
+            # Log partition configuration for debugging
+            if partition_prefix:
+                logger.info(
+                    f"✅ Detected partition files, using partition_prefix='{partition_prefix}'"
+                )
             self._diskannpy = diskannpy
             self._current_zmq_port = None
             self._index = None
@@ -259,7 +389,7 @@ class DiskannSearcher(BaseSearcher):
         prune_ratio: float = 0.0,
         recompute_embeddings: bool = False,
         pruning_strategy: Literal["global", "local", "proportional"] = "global",
-        zmq_port: int | None = None,
+        zmq_port: Optional[int] = None,
         batch_recompute: bool = False,
         dedup_node_dis: bool = False,
         **kwargs,
@@ -311,9 +441,14 @@ class DiskannSearcher(BaseSearcher):
         else:  # "global"
             use_global_pruning = True
 
-        # Perform search with suppressed C++ output based on log level
-        use_deferred_fetch = kwargs.get("USE_DEFERRED_FETCH", True)
-        recompute_neighors = False
+        # Strategy:
+        # - Traversal always uses PQ distances
+        # - If recompute_embeddings=True, do a single final rerank via deferred fetch
+        #   (fetch embeddings for the final candidate set only)
+        # - Do not recompute neighbor distances along the path
+        use_deferred_fetch = True if recompute_embeddings else False
+        recompute_neighors = False  # Expected typo. For backward compatibility.
+
         with suppress_cpp_output_if_needed():
             labels, distances = self._index.batch_search(
                 query,

packages/leann-backend-diskann/leann_backend_diskann/diskann_embedding_server.py

@@ -10,6 +10,7 @@ import sys
 import threading
 import time
 from pathlib import Path
+from typing import Optional
 
 import numpy as np
 import zmq
@@ -32,7 +33,7 @@ if not logger.handlers:
 
 
 def create_diskann_embedding_server(
-    passages_file: str | None = None,
+    passages_file: Optional[str] = None,
     zmq_port: int = 5555,
     model_name: str = "sentence-transformers/all-mpnet-base-v2",
     embedding_mode: str = "sentence-transformers",
@@ -80,10 +81,9 @@ def create_diskann_embedding_server(
     with open(passages_file) as f:
         meta = json.load(f)
 
-    passages = PassageManager(meta["passage_sources"])
-    logger.info(
-        f"Loaded PassageManager with {len(passages.global_offset_map)} passages from metadata"
-    )
+    logger.info(f"Loading PassageManager with metadata_file_path: {passages_file}")
+    passages = PassageManager(meta["passage_sources"], metadata_file_path=passages_file)
+    logger.info(f"Loaded PassageManager with {len(passages)} passages from metadata")
 
     # Import protobuf after ensuring the path is correct
     try:
@@ -101,8 +101,9 @@ def create_diskann_embedding_server(
         socket.bind(f"tcp://*:{zmq_port}")
         logger.info(f"DiskANN ZMQ REP server listening on port {zmq_port}")
 
-        socket.setsockopt(zmq.RCVTIMEO, 300000)
-        socket.setsockopt(zmq.SNDTIMEO, 300000)
+        socket.setsockopt(zmq.RCVTIMEO, 1000)
+        socket.setsockopt(zmq.SNDTIMEO, 1000)
+        socket.setsockopt(zmq.LINGER, 0)
 
         while True:
             try:
@@ -219,30 +220,217 @@ def create_diskann_embedding_server(
                 traceback.print_exc()
                 raise
 
-    zmq_thread = threading.Thread(target=zmq_server_thread, daemon=True)
+    def zmq_server_thread_with_shutdown(shutdown_event):
+        """ZMQ server thread that respects shutdown signal.
+
+        This creates its own REP socket, binds to zmq_port, and periodically
+        checks shutdown_event using recv timeouts to exit cleanly.
+        """
+        logger.info("DiskANN ZMQ server thread started with shutdown support")
+
+        context = zmq.Context()
+        rep_socket = context.socket(zmq.REP)
+        rep_socket.bind(f"tcp://*:{zmq_port}")
+        logger.info(f"DiskANN ZMQ REP server listening on port {zmq_port}")
+
+        # Set receive timeout so we can check shutdown_event periodically
+        rep_socket.setsockopt(zmq.RCVTIMEO, 1000)  # 1 second timeout
+        rep_socket.setsockopt(zmq.SNDTIMEO, 1000)
+        rep_socket.setsockopt(zmq.LINGER, 0)
+
+        try:
+            while not shutdown_event.is_set():
+                try:
+                    e2e_start = time.time()
+                    # REP socket receives single-part messages
+                    message = rep_socket.recv()
+
+                    # Check for empty messages - REP socket requires response to every request
+                    if not message:
+                        logger.warning("Received empty message, sending empty response")
+                        rep_socket.send(b"")
+                        continue
+
+                    # Try protobuf first (same logic as original)
+                    texts = []
+                    is_text_request = False
+
+                    try:
+                        req_proto = embedding_pb2.NodeEmbeddingRequest()
+                        req_proto.ParseFromString(message)
+                        node_ids = list(req_proto.node_ids)
+
+                        # Look up texts by node IDs
+                        for nid in node_ids:
+                            try:
+                                passage_data = passages.get_passage(str(nid))
+                                txt = passage_data["text"]
+                                if not txt:
+                                    raise RuntimeError(f"FATAL: Empty text for passage ID {nid}")
+                                texts.append(txt)
+                            except KeyError:
+                                raise RuntimeError(f"FATAL: Passage with ID {nid} not found")
+
+                        logger.info(f"ZMQ received protobuf request for {len(node_ids)} node IDs")
+                    except Exception:
+                        # Fallback to msgpack for text requests
+                        try:
+                            import msgpack
+
+                            request = msgpack.unpackb(message)
+                            if isinstance(request, list) and all(
+                                isinstance(item, str) for item in request
+                            ):
+                                texts = request
+                                is_text_request = True
+                                logger.info(
+                                    f"ZMQ received msgpack text request for {len(texts)} texts"
+                                )
+                            else:
+                                raise ValueError("Not a valid msgpack text request")
+                        except Exception:
+                            logger.error("Both protobuf and msgpack parsing failed!")
+                            # Send error response
+                            resp_proto = embedding_pb2.NodeEmbeddingResponse()
+                            rep_socket.send(resp_proto.SerializeToString())
+                            continue
+
+                    # Process the request
+                    embeddings = compute_embeddings(texts, model_name, mode=embedding_mode)
+                    logger.info(f"Computed embeddings shape: {embeddings.shape}")
+
+                    # Validation
+                    if np.isnan(embeddings).any() or np.isinf(embeddings).any():
+                        logger.error("NaN or Inf detected in embeddings!")
+                        # Send error response
+                        if is_text_request:
+                            import msgpack
+
+                            response_data = msgpack.packb([])
+                        else:
+                            resp_proto = embedding_pb2.NodeEmbeddingResponse()
+                            response_data = resp_proto.SerializeToString()
+                        rep_socket.send(response_data)
+                        continue
+
+                    # Prepare response based on request type
+                    if is_text_request:
+                        # For direct text requests, return msgpack
+                        import msgpack
+
+                        response_data = msgpack.packb(embeddings.tolist())
+                    else:
+                        # For protobuf requests, return protobuf
+                        resp_proto = embedding_pb2.NodeEmbeddingResponse()
+                        hidden_contiguous = np.ascontiguousarray(embeddings, dtype=np.float32)
+
+                        resp_proto.embeddings_data = hidden_contiguous.tobytes()
+                        resp_proto.dimensions.append(hidden_contiguous.shape[0])
+                        resp_proto.dimensions.append(hidden_contiguous.shape[1])
+
+                        response_data = resp_proto.SerializeToString()
+
+                    # Send response back to the client
+                    rep_socket.send(response_data)
+
+                    e2e_end = time.time()
+                    logger.info(f"⏱️  ZMQ E2E time: {e2e_end - e2e_start:.6f}s")
+
+                except zmq.Again:
+                    # Timeout - check shutdown_event and continue
+                    continue
+                except Exception as e:
+                    if not shutdown_event.is_set():
+                        logger.error(f"Error in ZMQ server loop: {e}")
+                        try:
+                            # Send error response for REP socket
+                            resp_proto = embedding_pb2.NodeEmbeddingResponse()
+                            rep_socket.send(resp_proto.SerializeToString())
+                        except Exception:
+                            pass
+                    else:
+                        logger.info("Shutdown in progress, ignoring ZMQ error")
+                        break
+        finally:
+            try:
+                rep_socket.close(0)
+            except Exception:
+                pass
+            try:
+                context.term()
+            except Exception:
+                pass
+
+        logger.info("DiskANN ZMQ server thread exiting gracefully")
+
+    # Add shutdown coordination
+    shutdown_event = threading.Event()
+
+    def shutdown_zmq_server():
+        """Gracefully shutdown ZMQ server."""
+        logger.info("Initiating graceful shutdown...")
+        shutdown_event.set()
+
+        if zmq_thread.is_alive():
+            logger.info("Waiting for ZMQ thread to finish...")
+            zmq_thread.join(timeout=5)
+            if zmq_thread.is_alive():
+                logger.warning("ZMQ thread did not finish in time")
+
+        # Clean up ZMQ resources
+        try:
+            # Note: socket and context are cleaned up by thread exit
+            logger.info("ZMQ resources cleaned up")
+        except Exception as e:
+            logger.warning(f"Error cleaning ZMQ resources: {e}")
+
+        # Clean up other resources
+        try:
+            import gc
+
+            gc.collect()
+            logger.info("Additional resources cleaned up")
+        except Exception as e:
+            logger.warning(f"Error cleaning additional resources: {e}")
+
+        logger.info("Graceful shutdown completed")
+        sys.exit(0)
+
+    # Register signal handlers within this function scope
+    import signal
+
+    def signal_handler(sig, frame):
+        logger.info(f"Received signal {sig}, shutting down gracefully...")
+        shutdown_zmq_server()
+
+    signal.signal(signal.SIGTERM, signal_handler)
+    signal.signal(signal.SIGINT, signal_handler)
+
+    # Start ZMQ thread (NOT daemon!)
+    zmq_thread = threading.Thread(
+        target=lambda: zmq_server_thread_with_shutdown(shutdown_event),
+        daemon=False,  # Not daemon - we want to wait for it
+    )
     zmq_thread.start()
     logger.info(f"Started DiskANN ZMQ server thread on port {zmq_port}")
 
     # Keep the main thread alive
     try:
-        while True:
-            time.sleep(1)
+        while not shutdown_event.is_set():
+            time.sleep(0.1)  # Check shutdown more frequently
     except KeyboardInterrupt:
         logger.info("DiskANN Server shutting down...")
+        shutdown_zmq_server()
         return
 
+    # If we reach here, shutdown was triggered by signal
+    logger.info("Main loop exited, process should be shutting down")
+
 
 if __name__ == "__main__":
-    import signal
     import sys
 
-    def signal_handler(sig, frame):
-        logger.info(f"Received signal {sig}, shutting down gracefully...")
-        sys.exit(0)
-
-    # Register signal handlers for graceful shutdown
-    signal.signal(signal.SIGTERM, signal_handler)
-    signal.signal(signal.SIGINT, signal_handler)
+    # Signal handlers are now registered within create_diskann_embedding_server
 
     parser = argparse.ArgumentParser(description="DiskANN Embedding service")
     parser.add_argument("--zmq-port", type=int, default=5555, help="ZMQ port to run on")

packages/leann-backend-diskann/leann_backend_diskann/graph_partition.py

@@ -0,0 +1,299 @@
+#!/usr/bin/env python3
+"""
+Graph Partition Module for LEANN DiskANN Backend
+
+This module provides Python bindings for the graph partition functionality
+of DiskANN, allowing users to partition disk-based indices for better
+performance.
+"""
+
+import os
+import shutil
+import subprocess
+import tempfile
+from pathlib import Path
+from typing import Optional
+
+
+class GraphPartitioner:
+    """
+    A Python interface for DiskANN's graph partition functionality.
+
+    This class provides methods to partition disk-based indices for improved
+    search performance and memory efficiency.
+    """
+
+    def __init__(self, build_type: str = "release"):
+        """
+        Initialize the GraphPartitioner.
+
+        Args:
+            build_type: Build type for the executables ("debug" or "release")
+        """
+        self.build_type = build_type
+        self._ensure_executables()
+
+    def _get_executable_path(self, name: str) -> str:
+        """Get the path to a graph partition executable."""
+        # Get the directory where this Python module is located
+        module_dir = Path(__file__).parent
+        # Navigate to the graph_partition directory
+        graph_partition_dir = module_dir.parent / "third_party" / "DiskANN" / "graph_partition"
+        executable_path = graph_partition_dir / "build" / self.build_type / "graph_partition" / name
+
+        if not executable_path.exists():
+            raise FileNotFoundError(f"Executable {name} not found at {executable_path}")
+
+        return str(executable_path)
+
+    def _ensure_executables(self):
+        """Ensure that the required executables are built."""
+        try:
+            self._get_executable_path("partitioner")
+            self._get_executable_path("index_relayout")
+        except FileNotFoundError:
+            # Try to build the executables automatically
+            print("Executables not found, attempting to build them...")
+            self._build_executables()
+
+    def _build_executables(self):
+        """Build the required executables."""
+        graph_partition_dir = (
+            Path(__file__).parent.parent / "third_party" / "DiskANN" / "graph_partition"
+        )
+        original_dir = os.getcwd()
+
+        try:
+            os.chdir(graph_partition_dir)
+
+            # Clean any existing build
+            if (graph_partition_dir / "build").exists():
+                shutil.rmtree(graph_partition_dir / "build")
+
+            # Run the build script
+            cmd = ["./build.sh", self.build_type, "split_graph", "/tmp/dummy"]
+            subprocess.run(cmd, capture_output=True, text=True, cwd=graph_partition_dir)
+
+            # Check if executables were created
+            partitioner_path = self._get_executable_path("partitioner")
+            relayout_path = self._get_executable_path("index_relayout")
+
+            print(f"✅ Built partitioner: {partitioner_path}")
+            print(f"✅ Built index_relayout: {relayout_path}")
+
+        except Exception as e:
+            raise RuntimeError(f"Failed to build executables: {e}")
+        finally:
+            os.chdir(original_dir)
+
+    def partition_graph(
+        self,
+        index_prefix_path: str,
+        output_dir: Optional[str] = None,
+        partition_prefix: Optional[str] = None,
+        **kwargs,
+    ) -> tuple[str, str]:
+        """
+        Partition a disk-based index for improved performance.
+
+        Args:
+            index_prefix_path: Path to the index prefix (e.g., "/path/to/index")
+            output_dir: Output directory for results (defaults to parent of index_prefix_path)
+            partition_prefix: Prefix for output files (defaults to basename of index_prefix_path)
+            **kwargs: Additional parameters for graph partitioning:
+                - gp_times: Number of LDG partition iterations (default: 10)
+                - lock_nums: Number of lock nodes (default: 10)
+                - cut: Cut adjacency list degree (default: 100)
+                - scale_factor: Scale factor (default: 1)
+                - data_type: Data type (default: "float")
+                - thread_nums: Number of threads (default: 10)
+
+        Returns:
+            Tuple of (disk_graph_index_path, partition_bin_path)
+
+        Raises:
+            RuntimeError: If the partitioning process fails
+        """
+        # Set default parameters
+        params = {
+            "gp_times": 10,
+            "lock_nums": 10,
+            "cut": 100,
+            "scale_factor": 1,
+            "data_type": "float",
+            "thread_nums": 10,
+            **kwargs,
+        }
+
+        # Determine output directory
+        if output_dir is None:
+            output_dir = str(Path(index_prefix_path).parent)
+
+        # Create output directory if it doesn't exist
+        Path(output_dir).mkdir(parents=True, exist_ok=True)
+
+        # Determine partition prefix
+        if partition_prefix is None:
+            partition_prefix = Path(index_prefix_path).name
+
+        # Get executable paths
+        partitioner_path = self._get_executable_path("partitioner")
+        relayout_path = self._get_executable_path("index_relayout")
+
+        # Create temporary directory for processing
+        with tempfile.TemporaryDirectory() as temp_dir:
+            # Change to the graph_partition directory for temporary files
+            graph_partition_dir = (
+                Path(__file__).parent.parent / "third_party" / "DiskANN" / "graph_partition"
+            )
+            original_dir = os.getcwd()
+
+            try:
+                os.chdir(graph_partition_dir)
+
+                # Create temporary data directory
+                temp_data_dir = Path(temp_dir) / "data"
+                temp_data_dir.mkdir(parents=True, exist_ok=True)
+
+                # Set up paths for temporary files
+                graph_path = temp_data_dir / "starling" / "_M_R_L_B" / "GRAPH"
+                graph_gp_path = (
+                    graph_path
+                    / f"GP_TIMES_{params['gp_times']}_LOCK_{params['lock_nums']}_GP_USE_FREQ0_CUT{params['cut']}_SCALE{params['scale_factor']}"
+                )
+                graph_gp_path.mkdir(parents=True, exist_ok=True)
+
+                # Find input index file
+                old_index_file = f"{index_prefix_path}_disk_beam_search.index"
+                if not os.path.exists(old_index_file):
+                    old_index_file = f"{index_prefix_path}_disk.index"
+
+                if not os.path.exists(old_index_file):
+                    raise RuntimeError(f"Index file not found: {old_index_file}")
+
+                # Run partitioner
+                gp_file_path = graph_gp_path / "_part.bin"
+                partitioner_cmd = [
+                    partitioner_path,
+                    "--index_file",
+                    old_index_file,
+                    "--data_type",
+                    params["data_type"],
+                    "--gp_file",
+                    str(gp_file_path),
+                    "-T",
+                    str(params["thread_nums"]),
+                    "--ldg_times",
+                    str(params["gp_times"]),
+                    "--scale",
+                    str(params["scale_factor"]),
+                    "--mode",
+                    "1",
+                ]
+
+                print(f"Running partitioner: {' '.join(partitioner_cmd)}")
+                result = subprocess.run(
+                    partitioner_cmd, capture_output=True, text=True, cwd=graph_partition_dir
+                )
+
+                if result.returncode != 0:
+                    raise RuntimeError(
+                        f"Partitioner failed with return code {result.returncode}.\n"
+                        f"stdout: {result.stdout}\n"
+                        f"stderr: {result.stderr}"
+                    )
+
+                # Run relayout
+                part_tmp_index = graph_gp_path / "_part_tmp.index"
+                relayout_cmd = [
+                    relayout_path,
+                    old_index_file,
+                    str(gp_file_path),
+                    params["data_type"],
+                    "1",
+                ]
+
+                print(f"Running relayout: {' '.join(relayout_cmd)}")
+                result = subprocess.run(
+                    relayout_cmd, capture_output=True, text=True, cwd=graph_partition_dir
+                )
+
+                if result.returncode != 0:
+                    raise RuntimeError(
+                        f"Relayout failed with return code {result.returncode}.\n"
+                        f"stdout: {result.stdout}\n"
+                        f"stderr: {result.stderr}"
+                    )
+
+                # Copy results to output directory
+                disk_graph_path = Path(output_dir) / f"{partition_prefix}_disk_graph.index"
+                partition_bin_path = Path(output_dir) / f"{partition_prefix}_partition.bin"
+
+                shutil.copy2(part_tmp_index, disk_graph_path)
+                shutil.copy2(gp_file_path, partition_bin_path)
+
+                print(f"Results copied to: {output_dir}")
+                return str(disk_graph_path), str(partition_bin_path)
+
+            finally:
+                os.chdir(original_dir)
+
+    def get_partition_info(self, partition_bin_path: str) -> dict:
+        """
+        Get information about a partition file.
+
+        Args:
+            partition_bin_path: Path to the partition binary file
+
+        Returns:
+            Dictionary containing partition information
+        """
+        if not os.path.exists(partition_bin_path):
+            raise FileNotFoundError(f"Partition file not found: {partition_bin_path}")
+
+        # For now, return basic file information
+        # In the future, this could parse the binary file for detailed info
+        stat = os.stat(partition_bin_path)
+        return {
+            "file_size": stat.st_size,
+            "file_path": partition_bin_path,
+            "modified_time": stat.st_mtime,
+        }
+
+
+def partition_graph(
+    index_prefix_path: str,
+    output_dir: Optional[str] = None,
+    partition_prefix: Optional[str] = None,
+    build_type: str = "release",
+    **kwargs,
+) -> tuple[str, str]:
+    """
+    Convenience function to partition a graph index.
+
+    Args:
+        index_prefix_path: Path to the index prefix
+        output_dir: Output directory (defaults to parent of index_prefix_path)
+        partition_prefix: Prefix for output files (defaults to basename of index_prefix_path)
+        build_type: Build type for executables ("debug" or "release")
+        **kwargs: Additional parameters for graph partitioning
+
+    Returns:
+        Tuple of (disk_graph_index_path, partition_bin_path)
+    """
+    partitioner = GraphPartitioner(build_type=build_type)
+    return partitioner.partition_graph(index_prefix_path, output_dir, partition_prefix, **kwargs)
+
+
+# Example usage:
+if __name__ == "__main__":
+    # Example: partition an index
+    try:
+        disk_graph_path, partition_bin_path = partition_graph(
+            "/path/to/your/index_prefix", gp_times=10, lock_nums=10, cut=100
+        )
+        print("Partitioning completed successfully!")
+        print(f"Disk graph index: {disk_graph_path}")
+        print(f"Partition binary: {partition_bin_path}")
+    except Exception as e:
+        print(f"Partitioning failed: {e}")

packages/leann-backend-diskann/pyproject.toml

@@ -1,11 +1,11 @@
 [build-system]
-requires = ["scikit-build-core>=0.10", "pybind11>=2.12.0", "numpy"]
+requires = ["scikit-build-core>=0.10", "pybind11>=2.12.0", "numpy", "cmake>=3.30"]
 build-backend = "scikit_build_core.build"
 
 [project]
 name = "leann-backend-diskann"
-version = "0.2.6"
-dependencies = ["leann-core==0.2.6", "numpy", "protobuf>=3.19.0"]
+version = "0.3.4"
+dependencies = ["leann-core==0.3.4", "numpy", "protobuf>=3.19.0"]
 
 [tool.scikit-build]
 # Key: simplified CMake path
@@ -17,3 +17,5 @@ editable.mode = "redirect"
 cmake.build-type = "Release"
 build.verbose = true
 build.tool-args = ["-j8"]
+# Let CMake find packages via Homebrew prefix
+cmake.define = {CMAKE_PREFIX_PATH = {env = "CMAKE_PREFIX_PATH"}, OpenMP_ROOT = {env = "OpenMP_ROOT"}}

packages/leann-backend-hnsw/CMakeLists.txt

@@ -5,11 +5,20 @@ set(CMAKE_CXX_COMPILER_WORKS 1)
 
 # Set OpenMP path for macOS
 if(APPLE)
-    set(OpenMP_C_FLAGS "-Xpreprocessor -fopenmp -I/opt/homebrew/opt/libomp/include")
-    set(OpenMP_CXX_FLAGS "-Xpreprocessor -fopenmp -I/opt/homebrew/opt/libomp/include")
+    # Detect Homebrew installation path (Apple Silicon vs Intel)
+    if(EXISTS "/opt/homebrew/opt/libomp")
+        set(HOMEBREW_PREFIX "/opt/homebrew")
+    elseif(EXISTS "/usr/local/opt/libomp")
+        set(HOMEBREW_PREFIX "/usr/local")
+    else()
+        message(FATAL_ERROR "Could not find libomp installation. Please install with: brew install libomp")
+    endif()
+
+    set(OpenMP_C_FLAGS "-Xpreprocessor -fopenmp -I${HOMEBREW_PREFIX}/opt/libomp/include")
+    set(OpenMP_CXX_FLAGS "-Xpreprocessor -fopenmp -I${HOMEBREW_PREFIX}/opt/libomp/include")
     set(OpenMP_C_LIB_NAMES "omp")
     set(OpenMP_CXX_LIB_NAMES "omp")
-    set(OpenMP_omp_LIBRARY "/opt/homebrew/opt/libomp/lib/libomp.dylib")
+    set(OpenMP_omp_LIBRARY "${HOMEBREW_PREFIX}/opt/libomp/lib/libomp.dylib")
 
     # Force use of system libc++ to avoid version mismatch
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -stdlib=libc++")
@@ -40,9 +49,28 @@ set(BUILD_TESTING OFF CACHE BOOL "" FORCE)
 set(FAISS_ENABLE_C_API OFF CACHE BOOL "" FORCE)
 set(FAISS_OPT_LEVEL "generic" CACHE STRING "" FORCE)
 
-# Disable additional SIMD versions to speed up compilation
+# Disable x86-specific SIMD optimizations (important for ARM64 compatibility)
 set(FAISS_ENABLE_AVX2 OFF CACHE BOOL "" FORCE)
 set(FAISS_ENABLE_AVX512 OFF CACHE BOOL "" FORCE)
+set(FAISS_ENABLE_SSE4_1 OFF CACHE BOOL "" FORCE)
+
+# ARM64-specific configuration
+if(CMAKE_SYSTEM_PROCESSOR MATCHES "aarch64|arm64")
+    message(STATUS "Configuring Faiss for ARM64 architecture")
+
+    if(CMAKE_SYSTEM_NAME STREQUAL "Linux")
+        # Use SVE optimization level for ARM64 Linux (as seen in Faiss conda build)
+        set(FAISS_OPT_LEVEL "sve" CACHE STRING "" FORCE)
+        message(STATUS "Setting FAISS_OPT_LEVEL to 'sve' for ARM64 Linux")
+    else()
+        # Use generic optimization for other ARM64 platforms (like macOS)
+        set(FAISS_OPT_LEVEL "generic" CACHE STRING "" FORCE)
+        message(STATUS "Setting FAISS_OPT_LEVEL to 'generic' for ARM64 ${CMAKE_SYSTEM_NAME}")
+    endif()
+
+    # ARM64 compatibility: Faiss submodule has been modified to fix x86 header inclusion
+    message(STATUS "Using ARM64-compatible Faiss submodule")
+endif()
 
 # Additional optimization options from INSTALL.md
 set(CMAKE_BUILD_TYPE "Release" CACHE STRING "" FORCE)

packages/leann-backend-hnsw/leann_backend_hnsw/convert_to_csr.py

@@ -1,12 +1,21 @@
 import argparse
 import gc  # Import garbage collector interface
+import logging
 import os
 import struct
 import sys
 import time
+from dataclasses import dataclass
+from typing import Any, Optional
 
 import numpy as np
 
+# Set up logging to avoid print buffer issues
+logger = logging.getLogger(__name__)
+LOG_LEVEL = os.getenv("LEANN_LOG_LEVEL", "WARNING").upper()
+log_level = getattr(logging, LOG_LEVEL, logging.WARNING)
+logger.setLevel(log_level)
+
 # --- FourCCs (add more if needed) ---
 INDEX_HNSW_FLAT_FOURCC = int.from_bytes(b"IHNf", "little")
 # Add other HNSW fourccs if you expect different storage types inside HNSW
@@ -230,6 +239,288 @@ def write_compact_format(
         f_out.write(storage_data)
 
 
+@dataclass
+class HNSWComponents:
+    original_hnsw_data: dict[str, Any]
+    assign_probas_np: np.ndarray
+    cum_nneighbor_per_level_np: np.ndarray
+    levels_np: np.ndarray
+    is_compact: bool
+    compact_level_ptr: Optional[np.ndarray] = None
+    compact_node_offsets_np: Optional[np.ndarray] = None
+    compact_neighbors_data: Optional[list[int]] = None
+    offsets_np: Optional[np.ndarray] = None
+    neighbors_np: Optional[np.ndarray] = None
+    storage_fourcc: int = NULL_INDEX_FOURCC
+    storage_data: bytes = b""
+
+
+def _read_hnsw_structure(f) -> HNSWComponents:
+    original_hnsw_data: dict[str, Any] = {}
+
+    hnsw_index_fourcc = read_struct(f, "<I")
+    if hnsw_index_fourcc not in EXPECTED_HNSW_FOURCCS:
+        raise ValueError(
+            f"Unexpected HNSW FourCC: {hnsw_index_fourcc:08x}. Expected one of {EXPECTED_HNSW_FOURCCS}."
+        )
+
+    original_hnsw_data["index_fourcc"] = hnsw_index_fourcc
+    original_hnsw_data["d"] = read_struct(f, "<i")
+    original_hnsw_data["ntotal"] = read_struct(f, "<q")
+    original_hnsw_data["dummy1"] = read_struct(f, "<q")
+    original_hnsw_data["dummy2"] = read_struct(f, "<q")
+    original_hnsw_data["is_trained"] = read_struct(f, "?")
+    original_hnsw_data["metric_type"] = read_struct(f, "<i")
+    original_hnsw_data["metric_arg"] = 0.0
+    if original_hnsw_data["metric_type"] > 1:
+        original_hnsw_data["metric_arg"] = read_struct(f, "<f")
+
+    assign_probas_np = read_numpy_vector(f, np.float64, "d")
+    cum_nneighbor_per_level_np = read_numpy_vector(f, np.int32, "i")
+    levels_np = read_numpy_vector(f, np.int32, "i")
+
+    ntotal = len(levels_np)
+    if ntotal != original_hnsw_data["ntotal"]:
+        original_hnsw_data["ntotal"] = ntotal
+
+    pos_before_compact = f.tell()
+    is_compact_flag = None
+    try:
+        is_compact_flag = read_struct(f, "<?")
+    except EOFError:
+        is_compact_flag = None
+
+    if is_compact_flag:
+        compact_level_ptr = read_numpy_vector(f, np.uint64, "Q")
+        compact_node_offsets_np = read_numpy_vector(f, np.uint64, "Q")
+
+        original_hnsw_data["entry_point"] = read_struct(f, "<i")
+        original_hnsw_data["max_level"] = read_struct(f, "<i")
+        original_hnsw_data["efConstruction"] = read_struct(f, "<i")
+        original_hnsw_data["efSearch"] = read_struct(f, "<i")
+        original_hnsw_data["dummy_upper_beam"] = read_struct(f, "<i")
+
+        storage_fourcc = read_struct(f, "<I")
+        compact_neighbors_data_np = read_numpy_vector(f, np.int32, "i")
+        compact_neighbors_data = compact_neighbors_data_np.tolist()
+        storage_data = f.read()
+
+        return HNSWComponents(
+            original_hnsw_data=original_hnsw_data,
+            assign_probas_np=assign_probas_np,
+            cum_nneighbor_per_level_np=cum_nneighbor_per_level_np,
+            levels_np=levels_np,
+            is_compact=True,
+            compact_level_ptr=compact_level_ptr,
+            compact_node_offsets_np=compact_node_offsets_np,
+            compact_neighbors_data=compact_neighbors_data,
+            storage_fourcc=storage_fourcc,
+            storage_data=storage_data,
+        )
+
+    # Non-compact case
+    f.seek(pos_before_compact)
+
+    pos_before_probe = f.tell()
+    try:
+        suspected_flag = read_struct(f, "<B")
+        if suspected_flag != 0x00:
+            f.seek(pos_before_probe)
+    except EOFError:
+        f.seek(pos_before_probe)
+
+    offsets_np = read_numpy_vector(f, np.uint64, "Q")
+    neighbors_np = read_numpy_vector(f, np.int32, "i")
+
+    original_hnsw_data["entry_point"] = read_struct(f, "<i")
+    original_hnsw_data["max_level"] = read_struct(f, "<i")
+    original_hnsw_data["efConstruction"] = read_struct(f, "<i")
+    original_hnsw_data["efSearch"] = read_struct(f, "<i")
+    original_hnsw_data["dummy_upper_beam"] = read_struct(f, "<i")
+
+    storage_fourcc = NULL_INDEX_FOURCC
+    storage_data = b""
+    try:
+        storage_fourcc = read_struct(f, "<I")
+        storage_data = f.read()
+    except EOFError:
+        storage_fourcc = NULL_INDEX_FOURCC
+
+    return HNSWComponents(
+        original_hnsw_data=original_hnsw_data,
+        assign_probas_np=assign_probas_np,
+        cum_nneighbor_per_level_np=cum_nneighbor_per_level_np,
+        levels_np=levels_np,
+        is_compact=False,
+        offsets_np=offsets_np,
+        neighbors_np=neighbors_np,
+        storage_fourcc=storage_fourcc,
+        storage_data=storage_data,
+    )
+
+
+def _read_hnsw_structure_from_file(path: str) -> HNSWComponents:
+    with open(path, "rb") as f:
+        return _read_hnsw_structure(f)
+
+
+def write_original_format(
+    f_out,
+    original_hnsw_data,
+    assign_probas_np,
+    cum_nneighbor_per_level_np,
+    levels_np,
+    offsets_np,
+    neighbors_np,
+    storage_fourcc,
+    storage_data,
+):
+    """Write non-compact HNSW data in original FAISS order."""
+
+    f_out.write(struct.pack("<I", original_hnsw_data["index_fourcc"]))
+    f_out.write(struct.pack("<i", original_hnsw_data["d"]))
+    f_out.write(struct.pack("<q", original_hnsw_data["ntotal"]))
+    f_out.write(struct.pack("<q", original_hnsw_data["dummy1"]))
+    f_out.write(struct.pack("<q", original_hnsw_data["dummy2"]))
+    f_out.write(struct.pack("<?", original_hnsw_data["is_trained"]))
+    f_out.write(struct.pack("<i", original_hnsw_data["metric_type"]))
+    if original_hnsw_data["metric_type"] > 1:
+        f_out.write(struct.pack("<f", original_hnsw_data["metric_arg"]))
+
+    write_numpy_vector(f_out, assign_probas_np, "d")
+    write_numpy_vector(f_out, cum_nneighbor_per_level_np, "i")
+    write_numpy_vector(f_out, levels_np, "i")
+
+    write_numpy_vector(f_out, offsets_np, "Q")
+    write_numpy_vector(f_out, neighbors_np, "i")
+
+    f_out.write(struct.pack("<i", original_hnsw_data["entry_point"]))
+    f_out.write(struct.pack("<i", original_hnsw_data["max_level"]))
+    f_out.write(struct.pack("<i", original_hnsw_data["efConstruction"]))
+    f_out.write(struct.pack("<i", original_hnsw_data["efSearch"]))
+    f_out.write(struct.pack("<i", original_hnsw_data["dummy_upper_beam"]))
+
+    f_out.write(struct.pack("<I", storage_fourcc))
+    if storage_fourcc != NULL_INDEX_FOURCC and storage_data:
+        f_out.write(storage_data)
+
+
+def prune_hnsw_embeddings(input_filename: str, output_filename: str) -> bool:
+    """Rewrite an HNSW index while dropping the embedded storage section."""
+
+    start_time = time.time()
+    try:
+        with open(input_filename, "rb") as f_in, open(output_filename, "wb") as f_out:
+            original_hnsw_data: dict[str, Any] = {}
+
+            hnsw_index_fourcc = read_struct(f_in, "<I")
+            if hnsw_index_fourcc not in EXPECTED_HNSW_FOURCCS:
+                print(
+                    f"Error: Expected HNSW Index FourCC ({list(EXPECTED_HNSW_FOURCCS)}), got {hnsw_index_fourcc:08x}.",
+                    file=sys.stderr,
+                )
+                return False
+
+            original_hnsw_data["index_fourcc"] = hnsw_index_fourcc
+            original_hnsw_data["d"] = read_struct(f_in, "<i")
+            original_hnsw_data["ntotal"] = read_struct(f_in, "<q")
+            original_hnsw_data["dummy1"] = read_struct(f_in, "<q")
+            original_hnsw_data["dummy2"] = read_struct(f_in, "<q")
+            original_hnsw_data["is_trained"] = read_struct(f_in, "?")
+            original_hnsw_data["metric_type"] = read_struct(f_in, "<i")
+            original_hnsw_data["metric_arg"] = 0.0
+            if original_hnsw_data["metric_type"] > 1:
+                original_hnsw_data["metric_arg"] = read_struct(f_in, "<f")
+
+            assign_probas_np = read_numpy_vector(f_in, np.float64, "d")
+            cum_nneighbor_per_level_np = read_numpy_vector(f_in, np.int32, "i")
+            levels_np = read_numpy_vector(f_in, np.int32, "i")
+
+            ntotal = len(levels_np)
+            if ntotal != original_hnsw_data["ntotal"]:
+                original_hnsw_data["ntotal"] = ntotal
+
+            pos_before_compact = f_in.tell()
+            is_compact_flag = None
+            try:
+                is_compact_flag = read_struct(f_in, "<?")
+            except EOFError:
+                is_compact_flag = None
+
+            if is_compact_flag:
+                compact_level_ptr = read_numpy_vector(f_in, np.uint64, "Q")
+                compact_node_offsets_np = read_numpy_vector(f_in, np.uint64, "Q")
+
+                original_hnsw_data["entry_point"] = read_struct(f_in, "<i")
+                original_hnsw_data["max_level"] = read_struct(f_in, "<i")
+                original_hnsw_data["efConstruction"] = read_struct(f_in, "<i")
+                original_hnsw_data["efSearch"] = read_struct(f_in, "<i")
+                original_hnsw_data["dummy_upper_beam"] = read_struct(f_in, "<i")
+
+                _storage_fourcc = read_struct(f_in, "<I")
+                compact_neighbors_data_np = read_numpy_vector(f_in, np.int32, "i")
+                compact_neighbors_data = compact_neighbors_data_np.tolist()
+                _storage_data = f_in.read()
+
+                write_compact_format(
+                    f_out,
+                    original_hnsw_data,
+                    assign_probas_np,
+                    cum_nneighbor_per_level_np,
+                    levels_np,
+                    compact_level_ptr,
+                    compact_node_offsets_np,
+                    compact_neighbors_data,
+                    NULL_INDEX_FOURCC,
+                    b"",
+                )
+            else:
+                f_in.seek(pos_before_compact)
+
+                pos_before_probe = f_in.tell()
+                try:
+                    suspected_flag = read_struct(f_in, "<B")
+                    if suspected_flag != 0x00:
+                        f_in.seek(pos_before_probe)
+                except EOFError:
+                    f_in.seek(pos_before_probe)
+
+                offsets_np = read_numpy_vector(f_in, np.uint64, "Q")
+                neighbors_np = read_numpy_vector(f_in, np.int32, "i")
+
+                original_hnsw_data["entry_point"] = read_struct(f_in, "<i")
+                original_hnsw_data["max_level"] = read_struct(f_in, "<i")
+                original_hnsw_data["efConstruction"] = read_struct(f_in, "<i")
+                original_hnsw_data["efSearch"] = read_struct(f_in, "<i")
+                original_hnsw_data["dummy_upper_beam"] = read_struct(f_in, "<i")
+
+                _storage_fourcc = None
+                _storage_data = b""
+                try:
+                    _storage_fourcc = read_struct(f_in, "<I")
+                    _storage_data = f_in.read()
+                except EOFError:
+                    _storage_fourcc = NULL_INDEX_FOURCC
+
+                write_original_format(
+                    f_out,
+                    original_hnsw_data,
+                    assign_probas_np,
+                    cum_nneighbor_per_level_np,
+                    levels_np,
+                    offsets_np,
+                    neighbors_np,
+                    NULL_INDEX_FOURCC,
+                    b"",
+                )
+
+        print(f"[{time.time() - start_time:.2f}s] Pruned embeddings from {input_filename}")
+        return True
+    except Exception as exc:
+        print(f"Failed to prune embeddings: {exc}", file=sys.stderr)
+        return False
+
+
 # --- Main Conversion Logic ---
 
 
@@ -243,6 +534,8 @@ def convert_hnsw_graph_to_csr(input_filename, output_filename, prune_embeddings=
         output_filename: Output CSR index file
         prune_embeddings: Whether to prune embedding storage (write NULL storage marker)
     """
+    # Keep prints simple; rely on CI runner to flush output as needed
+
     print(f"Starting conversion: {input_filename} -> {output_filename}")
     start_time = time.time()
     original_hnsw_data = {}
@@ -691,6 +984,29 @@ def convert_hnsw_graph_to_csr(input_filename, output_filename, prune_embeddings=
             pass
 
 
+def prune_hnsw_embeddings_inplace(index_filename: str) -> bool:
+    """Convenience wrapper to prune embeddings in-place."""
+
+    temp_path = f"{index_filename}.prune.tmp"
+    success = prune_hnsw_embeddings(index_filename, temp_path)
+    if success:
+        try:
+            os.replace(temp_path, index_filename)
+        except Exception as exc:  # pragma: no cover - defensive
+            logger.error(f"Failed to replace original index with pruned version: {exc}")
+            try:
+                os.remove(temp_path)
+            except OSError:
+                pass
+            return False
+    else:
+        try:
+            os.remove(temp_path)
+        except OSError:
+            pass
+    return success
+
+
 # --- Script Execution ---
 if __name__ == "__main__":
     parser = argparse.ArgumentParser(

packages/leann-backend-hnsw/leann_backend_hnsw/hnsw_backend.py

@@ -1,8 +1,9 @@
 import logging
 import os
 import shutil
+import time
 from pathlib import Path
-from typing import Any, Literal
+from typing import Any, Literal, Optional
 
 import numpy as np
 from leann.interface import (
@@ -13,7 +14,7 @@ from leann.interface import (
 from leann.registry import register_backend
 from leann.searcher_base import BaseSearcher
 
-from .convert_to_csr import convert_hnsw_graph_to_csr
+from .convert_to_csr import convert_hnsw_graph_to_csr, prune_hnsw_embeddings_inplace
 
 logger = logging.getLogger(__name__)
 
@@ -54,12 +55,13 @@ class HNSWBuilder(LeannBackendBuilderInterface):
         self.efConstruction = self.build_params.setdefault("efConstruction", 200)
         self.distance_metric = self.build_params.setdefault("distance_metric", "mips")
         self.dimensions = self.build_params.get("dimensions")
-        if not self.is_recompute:
-            if self.is_compact:
-                # TODO: support this case @andy
-                raise ValueError(
-                    "is_recompute is False, but is_compact is True. This is not compatible now. change is compact to False and you can use the original HNSW index."
-                )
+        if not self.is_recompute and self.is_compact:
+            # Auto-correct: non-recompute requires non-compact storage for HNSW
+            logger.warning(
+                "is_recompute=False requires non-compact HNSW. Forcing is_compact=False."
+            )
+            self.is_compact = False
+            self.build_params["is_compact"] = False
 
     def build(self, data: np.ndarray, ids: list[str], index_path: str, **kwargs):
         from . import faiss  # type: ignore
@@ -90,6 +92,8 @@ class HNSWBuilder(LeannBackendBuilderInterface):
 
         if self.is_compact:
             self._convert_to_csr(index_file)
+        elif self.is_recompute:
+            prune_hnsw_embeddings_inplace(str(index_file))
 
     def _convert_to_csr(self, index_file: Path):
         """Convert built index to CSR format"""
@@ -131,10 +135,10 @@ class HNSWSearcher(BaseSearcher):
         if metric_enum is None:
             raise ValueError(f"Unsupported distance_metric '{self.distance_metric}'.")
 
-        self.is_compact, self.is_pruned = (
-            self.meta.get("is_compact", True),
-            self.meta.get("is_pruned", True),
-        )
+        backend_meta_kwargs = self.meta.get("backend_kwargs", {})
+        self.is_compact = self.meta.get("is_compact", backend_meta_kwargs.get("is_compact", True))
+        default_pruned = backend_meta_kwargs.get("is_recompute", self.is_compact)
+        self.is_pruned = bool(self.meta.get("is_pruned", default_pruned))
 
         index_file = self.index_dir / f"{self.index_path.stem}.index"
         if not index_file.exists():
@@ -152,7 +156,7 @@ class HNSWSearcher(BaseSearcher):
         self,
         query: np.ndarray,
         top_k: int,
-        zmq_port: int | None = None,
+        zmq_port: Optional[int] = None,
         complexity: int = 64,
         beam_width: int = 1,
         prune_ratio: float = 0.0,
@@ -184,9 +188,11 @@ class HNSWSearcher(BaseSearcher):
         """
         from . import faiss  # type: ignore
 
-        if not recompute_embeddings:
-            if self.is_pruned:
-                raise RuntimeError("Recompute is required for pruned index.")
+        if not recompute_embeddings and self.is_pruned:
+            raise RuntimeError(
+                "Recompute is required for pruned/compact HNSW index. "
+                "Re-run search with --recompute, or rebuild with --no-recompute and --no-compact."
+            )
         if recompute_embeddings:
             if zmq_port is None:
                 raise ValueError("zmq_port must be provided if recompute_embeddings is True")
@@ -233,6 +239,7 @@ class HNSWSearcher(BaseSearcher):
         distances = np.empty((batch_size_query, top_k), dtype=np.float32)
         labels = np.empty((batch_size_query, top_k), dtype=np.int64)
 
+        search_time = time.time()
         self._index.search(
             query.shape[0],
             faiss.swig_ptr(query),
@@ -241,7 +248,8 @@ class HNSWSearcher(BaseSearcher):
             faiss.swig_ptr(labels),
             params,
         )
-
+        search_time = time.time() - search_time
+        logger.info(f"  Search time in HNSWSearcher.search() backend: {search_time} seconds")
         string_labels = [[str(int_label) for int_label in batch_labels] for batch_labels in labels]
 
         return {"labels": string_labels, "distances": distances}

packages/leann-backend-hnsw/leann_backend_hnsw/hnsw_embedding_server.py

@@ -10,6 +10,7 @@ import sys
 import threading
 import time
 from pathlib import Path
+from typing import Optional
 
 import msgpack
 import numpy as np
@@ -23,17 +24,30 @@ logger = logging.getLogger(__name__)
 log_level = getattr(logging, LOG_LEVEL, logging.WARNING)
 logger.setLevel(log_level)
 
-# Ensure we have a handler if none exists
+# Ensure we have handlers if none exist
 if not logger.handlers:
-    handler = logging.StreamHandler()
+    stream_handler = logging.StreamHandler()
     formatter = logging.Formatter("%(asctime)s - %(levelname)s - %(message)s")
-    handler.setFormatter(formatter)
-    logger.addHandler(handler)
-    logger.propagate = False
+    stream_handler.setFormatter(formatter)
+    logger.addHandler(stream_handler)
+
+log_path = os.getenv("LEANN_HNSW_LOG_PATH")
+if log_path:
+    try:
+        file_handler = logging.FileHandler(log_path, mode="a", encoding="utf-8")
+        file_formatter = logging.Formatter(
+            "%(asctime)s - %(levelname)s - [pid=%(process)d] %(message)s"
+        )
+        file_handler.setFormatter(file_formatter)
+        logger.addHandler(file_handler)
+    except Exception as exc:  # pragma: no cover - best effort logging
+        logger.warning(f"Failed to attach file handler for log path {log_path}: {exc}")
+
+logger.propagate = False
 
 
 def create_hnsw_embedding_server(
-    passages_file: str | None = None,
+    passages_file: Optional[str] = None,
     zmq_port: int = 5555,
     model_name: str = "sentence-transformers/all-mpnet-base-v2",
     distance_metric: str = "mips",
@@ -81,199 +95,315 @@ def create_hnsw_embedding_server(
     with open(passages_file) as f:
         meta = json.load(f)
 
-    # Convert relative paths to absolute paths based on metadata file location
-    metadata_dir = Path(passages_file).parent.parent  # Go up one level from the metadata file
-    passage_sources = []
-    for source in meta["passage_sources"]:
-        source_copy = source.copy()
-        # Convert relative paths to absolute paths
-        if not Path(source_copy["path"]).is_absolute():
-            source_copy["path"] = str(metadata_dir / source_copy["path"])
-        if not Path(source_copy["index_path"]).is_absolute():
-            source_copy["index_path"] = str(metadata_dir / source_copy["index_path"])
-        passage_sources.append(source_copy)
+    # Let PassageManager handle path resolution uniformly. It supports fallback order:
+    # 1) path/index_path; 2) *_relative; 3) standard siblings next to meta
+    passages = PassageManager(meta["passage_sources"], metadata_file_path=passages_file)
+    # Dimension from metadata for shaping responses
+    try:
+        embedding_dim: int = int(meta.get("dimensions", 0))
+    except Exception:
+        embedding_dim = 0
+    logger.info(f"Loaded PassageManager with {len(passages)} passages from metadata")
 
-    passages = PassageManager(passage_sources)
-    logger.info(
-        f"Loaded PassageManager with {len(passages.global_offset_map)} passages from metadata"
-    )
+    # (legacy ZMQ thread removed; using shutdown-capable server only)
+
+    def zmq_server_thread_with_shutdown(shutdown_event):
+        """ZMQ server thread that respects shutdown signal.
+
+        Creates its own REP socket bound to zmq_port and polls with timeouts
+        to allow graceful shutdown.
+        """
+        logger.info("ZMQ server thread started with shutdown support")
 
-    def zmq_server_thread():
-        """ZMQ server thread"""
         context = zmq.Context()
-        socket = context.socket(zmq.REP)
-        socket.bind(f"tcp://*:{zmq_port}")
-        logger.info(f"HNSW ZMQ server listening on port {zmq_port}")
+        rep_socket = context.socket(zmq.REP)
+        rep_socket.bind(f"tcp://*:{zmq_port}")
+        logger.info(f"HNSW ZMQ REP server listening on port {zmq_port}")
+        rep_socket.setsockopt(zmq.RCVTIMEO, 1000)
+        # Keep sends from blocking during shutdown; fail fast and drop on close
+        rep_socket.setsockopt(zmq.SNDTIMEO, 1000)
+        rep_socket.setsockopt(zmq.LINGER, 0)
 
-        socket.setsockopt(zmq.RCVTIMEO, 300000)
-        socket.setsockopt(zmq.SNDTIMEO, 300000)
+        # Track last request type/length for shape-correct fallbacks
+        last_request_type = "unknown"  # 'text' | 'distance' | 'embedding' | 'unknown'
+        last_request_length = 0
 
-        while True:
-            try:
-                message_bytes = socket.recv()
-                logger.debug(f"Received ZMQ request of size {len(message_bytes)} bytes")
+        try:
+            while not shutdown_event.is_set():
+                try:
+                    e2e_start = time.time()
+                    logger.debug("🔍 Waiting for ZMQ message...")
+                    request_bytes = rep_socket.recv()
 
-                e2e_start = time.time()
-                request_payload = msgpack.unpackb(message_bytes)
+                    # Rest of the processing logic (same as original)
+                    request = msgpack.unpackb(request_bytes)
 
-                # Handle direct text embedding request
-                if isinstance(request_payload, list) and len(request_payload) > 0:
-                    # Check if this is a direct text request (list of strings)
-                    if all(isinstance(item, str) for item in request_payload):
-                        logger.info(
-                            f"Processing direct text embedding request for {len(request_payload)} texts in {embedding_mode} mode"
-                        )
+                    if len(request) == 1 and request[0] == "__QUERY_MODEL__":
+                        response_bytes = msgpack.packb([model_name])
+                        rep_socket.send(response_bytes)
+                        continue
 
-                        # Use unified embedding computation (now with model caching)
-                        embeddings = compute_embeddings(
-                            request_payload, model_name, mode=embedding_mode
-                        )
-
-                        response = embeddings.tolist()
-                        socket.send(msgpack.packb(response))
+                    # Handle direct text embedding request
+                    if (
+                        isinstance(request, list)
+                        and request
+                        and all(isinstance(item, str) for item in request)
+                    ):
+                        last_request_type = "text"
+                        last_request_length = len(request)
+                        embeddings = compute_embeddings(request, model_name, mode=embedding_mode)
+                        rep_socket.send(msgpack.packb(embeddings.tolist()))
                         e2e_end = time.time()
                         logger.info(f"⏱️  Text embedding E2E time: {e2e_end - e2e_start:.6f}s")
                         continue
 
-                # Handle distance calculation requests
-                if (
-                    isinstance(request_payload, list)
-                    and len(request_payload) == 2
-                    and isinstance(request_payload[0], list)
-                    and isinstance(request_payload[1], list)
-                ):
-                    node_ids = request_payload[0]
-                    query_vector = np.array(request_payload[1], dtype=np.float32)
+                    # Handle distance calculation request: [[ids], [query_vector]]
+                    if (
+                        isinstance(request, list)
+                        and len(request) == 2
+                        and isinstance(request[0], list)
+                        and isinstance(request[1], list)
+                    ):
+                        node_ids = request[0]
+                        # Handle nested [[ids]] shape defensively
+                        if len(node_ids) == 1 and isinstance(node_ids[0], list):
+                            node_ids = node_ids[0]
+                        query_vector = np.array(request[1], dtype=np.float32)
+                        last_request_type = "distance"
+                        last_request_length = len(node_ids)
 
-                    logger.debug("Distance calculation request received")
-                    logger.debug(f"    Node IDs: {node_ids}")
-                    logger.debug(f"    Query vector dim: {len(query_vector)}")
+                        logger.debug("Distance calculation request received")
+                        logger.debug(f"    Node IDs: {node_ids}")
+                        logger.debug(f"    Query vector dim: {len(query_vector)}")
 
-                    # Get embeddings for node IDs
-                    texts = []
-                    for nid in node_ids:
+                        # Gather texts for found ids
+                        texts: list[str] = []
+                        found_indices: list[int] = []
+                        for idx, nid in enumerate(node_ids):
+                            try:
+                                passage_data = passages.get_passage(str(nid))
+                                txt = passage_data.get("text", "")
+                                if isinstance(txt, str) and len(txt) > 0:
+                                    texts.append(txt)
+                                    found_indices.append(idx)
+                                else:
+                                    logger.error(f"Empty text for passage ID {nid}")
+                            except KeyError:
+                                logger.error(f"Passage ID {nid} not found")
+                            except Exception as e:
+                                logger.error(f"Exception looking up passage ID {nid}: {e}")
+
+                        # Prepare full-length response with large sentinel values
+                        large_distance = 1e9
+                        response_distances = [large_distance] * len(node_ids)
+
+                        if texts:
+                            try:
+                                embeddings = compute_embeddings(
+                                    texts, model_name, mode=embedding_mode
+                                )
+                                logger.info(
+                                    f"Computed embeddings for {len(texts)} texts, shape: {embeddings.shape}"
+                                )
+                                if distance_metric == "l2":
+                                    partial = np.sum(
+                                        np.square(embeddings - query_vector.reshape(1, -1)), axis=1
+                                    )
+                                else:  # mips or cosine
+                                    partial = -np.dot(embeddings, query_vector)
+
+                                for pos, dval in zip(found_indices, partial.flatten().tolist()):
+                                    response_distances[pos] = float(dval)
+                            except Exception as e:
+                                logger.error(f"Distance computation error, using sentinels: {e}")
+
+                        # Send response in expected shape [[distances]]
+                        rep_socket.send(msgpack.packb([response_distances], use_single_float=True))
+                        e2e_end = time.time()
+                        logger.info(f"⏱️  Distance calculation E2E time: {e2e_end - e2e_start:.6f}s")
+                        continue
+
+                    # Fallback: treat as embedding-by-id request
+                    if (
+                        isinstance(request, list)
+                        and len(request) == 1
+                        and isinstance(request[0], list)
+                    ):
+                        node_ids = request[0]
+                    elif isinstance(request, list):
+                        node_ids = request
+                    else:
+                        node_ids = []
+                    last_request_type = "embedding"
+                    last_request_length = len(node_ids)
+                    logger.info(f"ZMQ received {len(node_ids)} node IDs for embedding fetch")
+
+                    # Preallocate zero-filled flat data for robustness
+                    if embedding_dim <= 0:
+                        dims = [0, 0]
+                        flat_data: list[float] = []
+                    else:
+                        dims = [len(node_ids), embedding_dim]
+                        flat_data = [0.0] * (dims[0] * dims[1])
+
+                    # Collect texts for found ids
+                    texts: list[str] = []
+                    found_indices: list[int] = []
+                    for idx, nid in enumerate(node_ids):
                         try:
                             passage_data = passages.get_passage(str(nid))
-                            txt = passage_data["text"]
-                            texts.append(txt)
+                            txt = passage_data.get("text", "")
+                            if isinstance(txt, str) and len(txt) > 0:
+                                texts.append(txt)
+                                found_indices.append(idx)
+                            else:
+                                logger.error(f"Empty text for passage ID {nid}")
                         except KeyError:
-                            logger.error(f"Passage ID {nid} not found")
-                            raise RuntimeError(f"FATAL: Passage with ID {nid} not found")
+                            logger.error(f"Passage with ID {nid} not found")
                         except Exception as e:
                             logger.error(f"Exception looking up passage ID {nid}: {e}")
-                            raise
 
-                    # Process embeddings
-                    embeddings = compute_embeddings(texts, model_name, mode=embedding_mode)
-                    logger.info(
-                        f"Computed embeddings for {len(texts)} texts, shape: {embeddings.shape}"
-                    )
+                    if texts:
+                        try:
+                            embeddings = compute_embeddings(texts, model_name, mode=embedding_mode)
+                            logger.info(
+                                f"Computed embeddings for {len(texts)} texts, shape: {embeddings.shape}"
+                            )
 
-                    # Calculate distances
-                    if distance_metric == "l2":
-                        distances = np.sum(
-                            np.square(embeddings - query_vector.reshape(1, -1)), axis=1
-                        )
-                    else:  # mips or cosine
-                        distances = -np.dot(embeddings, query_vector)
+                            if np.isnan(embeddings).any() or np.isinf(embeddings).any():
+                                logger.error(
+                                    f"NaN or Inf detected in embeddings! Requested IDs: {node_ids[:5]}..."
+                                )
+                                dims = [0, embedding_dim]
+                                flat_data = []
+                            else:
+                                emb_f32 = np.ascontiguousarray(embeddings, dtype=np.float32)
+                                flat = emb_f32.flatten().tolist()
+                                for j, pos in enumerate(found_indices):
+                                    start = pos * embedding_dim
+                                    end = start + embedding_dim
+                                    if end <= len(flat_data):
+                                        flat_data[start:end] = flat[
+                                            j * embedding_dim : (j + 1) * embedding_dim
+                                        ]
+                        except Exception as e:
+                            logger.error(f"Embedding computation error, returning zeros: {e}")
 
-                    response_payload = distances.flatten().tolist()
-                    response_bytes = msgpack.packb([response_payload], use_single_float=True)
-                    logger.debug(f"Sending distance response with {len(distances)} distances")
+                    response_payload = [dims, flat_data]
+                    response_bytes = msgpack.packb(response_payload, use_single_float=True)
 
-                    socket.send(response_bytes)
+                    rep_socket.send(response_bytes)
                     e2e_end = time.time()
-                    logger.info(f"⏱️  Distance calculation E2E time: {e2e_end - e2e_start:.6f}s")
+                    logger.info(f"⏱️  ZMQ E2E time: {e2e_end - e2e_start:.6f}s")
+
+                except zmq.Again:
+                    # Timeout - check shutdown_event and continue
                     continue
+                except Exception as e:
+                    if not shutdown_event.is_set():
+                        logger.error(f"Error in ZMQ server loop: {e}")
+                        # Shape-correct fallback
+                        try:
+                            if last_request_type == "distance":
+                                large_distance = 1e9
+                                fallback_len = max(0, int(last_request_length))
+                                safe = [[large_distance] * fallback_len]
+                            elif last_request_type == "embedding":
+                                bsz = max(0, int(last_request_length))
+                                dim = max(0, int(embedding_dim))
+                                safe = (
+                                    [[bsz, dim], [0.0] * (bsz * dim)] if dim > 0 else [[0, 0], []]
+                                )
+                            elif last_request_type == "text":
+                                safe = []  # direct text embeddings expectation is a flat list
+                            else:
+                                safe = [[0, int(embedding_dim) if embedding_dim > 0 else 0], []]
+                            rep_socket.send(msgpack.packb(safe, use_single_float=True))
+                        except Exception:
+                            pass
+                    else:
+                        logger.info("Shutdown in progress, ignoring ZMQ error")
+                        break
+        finally:
+            try:
+                rep_socket.close(0)
+            except Exception:
+                pass
+            try:
+                context.term()
+            except Exception:
+                pass
 
-                # Standard embedding request (passage ID lookup)
-                if (
-                    not isinstance(request_payload, list)
-                    or len(request_payload) != 1
-                    or not isinstance(request_payload[0], list)
-                ):
-                    logger.error(
-                        f"Invalid MessagePack request format. Expected [[ids...]] or [texts...], got: {type(request_payload)}"
-                    )
-                    socket.send(msgpack.packb([[], []]))
-                    continue
+        logger.info("ZMQ server thread exiting gracefully")
 
-                node_ids = request_payload[0]
-                logger.debug(f"Request for {len(node_ids)} node embeddings")
+    # Add shutdown coordination
+    shutdown_event = threading.Event()
 
-                # Look up texts by node IDs
-                texts = []
-                for nid in node_ids:
-                    try:
-                        passage_data = passages.get_passage(str(nid))
-                        txt = passage_data["text"]
-                        if not txt:
-                            raise RuntimeError(f"FATAL: Empty text for passage ID {nid}")
-                        texts.append(txt)
-                    except KeyError:
-                        raise RuntimeError(f"FATAL: Passage with ID {nid} not found")
-                    except Exception as e:
-                        logger.error(f"Exception looking up passage ID {nid}: {e}")
-                        raise
+    def shutdown_zmq_server():
+        """Gracefully shutdown ZMQ server."""
+        logger.info("Initiating graceful shutdown...")
+        shutdown_event.set()
 
-                # Process embeddings
-                embeddings = compute_embeddings(texts, model_name, mode=embedding_mode)
-                logger.info(
-                    f"Computed embeddings for {len(texts)} texts, shape: {embeddings.shape}"
-                )
+        if zmq_thread.is_alive():
+            logger.info("Waiting for ZMQ thread to finish...")
+            zmq_thread.join(timeout=5)
+            if zmq_thread.is_alive():
+                logger.warning("ZMQ thread did not finish in time")
 
-                # Serialization and response
-                if np.isnan(embeddings).any() or np.isinf(embeddings).any():
-                    logger.error(
-                        f"NaN or Inf detected in embeddings! Requested IDs: {node_ids[:5]}..."
-                    )
-                    raise AssertionError()
+        # Clean up ZMQ resources
+        try:
+            # Note: socket and context are cleaned up by thread exit
+            logger.info("ZMQ resources cleaned up")
+        except Exception as e:
+            logger.warning(f"Error cleaning ZMQ resources: {e}")
 
-                hidden_contiguous_f32 = np.ascontiguousarray(embeddings, dtype=np.float32)
-                response_payload = [
-                    list(hidden_contiguous_f32.shape),
-                    hidden_contiguous_f32.flatten().tolist(),
-                ]
-                response_bytes = msgpack.packb(response_payload, use_single_float=True)
+        # Clean up other resources
+        try:
+            import gc
 
-                socket.send(response_bytes)
-                e2e_end = time.time()
-                logger.info(f"⏱️  ZMQ E2E time: {e2e_end - e2e_start:.6f}s")
+            gc.collect()
+            logger.info("Additional resources cleaned up")
+        except Exception as e:
+            logger.warning(f"Error cleaning additional resources: {e}")
 
-            except zmq.Again:
-                logger.debug("ZMQ socket timeout, continuing to listen")
-                continue
-            except Exception as e:
-                logger.error(f"Error in ZMQ server loop: {e}")
-                import traceback
+        logger.info("Graceful shutdown completed")
+        sys.exit(0)
 
-                traceback.print_exc()
-                socket.send(msgpack.packb([[], []]))
+    # Register signal handlers within this function scope
+    import signal
 
-    zmq_thread = threading.Thread(target=zmq_server_thread, daemon=True)
+    def signal_handler(sig, frame):
+        logger.info(f"Received signal {sig}, shutting down gracefully...")
+        shutdown_zmq_server()
+
+    signal.signal(signal.SIGTERM, signal_handler)
+    signal.signal(signal.SIGINT, signal_handler)
+
+    # Pass shutdown_event to ZMQ thread
+    zmq_thread = threading.Thread(
+        target=lambda: zmq_server_thread_with_shutdown(shutdown_event),
+        daemon=False,  # Not daemon - we want to wait for it
+    )
     zmq_thread.start()
     logger.info(f"Started HNSW ZMQ server thread on port {zmq_port}")
 
     # Keep the main thread alive
     try:
-        while True:
-            time.sleep(1)
+        while not shutdown_event.is_set():
+            time.sleep(0.1)  # Check shutdown more frequently
     except KeyboardInterrupt:
         logger.info("HNSW Server shutting down...")
+        shutdown_zmq_server()
         return
 
+    # If we reach here, shutdown was triggered by signal
+    logger.info("Main loop exited, process should be shutting down")
+
 
 if __name__ == "__main__":
-    import signal
     import sys
 
-    def signal_handler(sig, frame):
-        logger.info(f"Received signal {sig}, shutting down gracefully...")
-        sys.exit(0)
-
-    # Register signal handlers for graceful shutdown
-    signal.signal(signal.SIGTERM, signal_handler)
-    signal.signal(signal.SIGINT, signal_handler)
+    # Signal handlers are now registered within create_hnsw_embedding_server
 
     parser = argparse.ArgumentParser(description="HNSW Embedding service")
     parser.add_argument("--zmq-port", type=int, default=5555, help="ZMQ port to run on")

packages/leann-backend-hnsw/pyproject.toml

@@ -6,10 +6,10 @@ build-backend = "scikit_build_core.build"
 
 [project]
 name = "leann-backend-hnsw"
-version = "0.2.6"
+version = "0.3.4"
 description = "Custom-built HNSW (Faiss) backend for the Leann toolkit."
 dependencies = [
-    "leann-core==0.2.6",
+    "leann-core==0.3.4",
     "numpy",
     "pyzmq>=23.0.0",
     "msgpack>=1.0.0",
@@ -22,6 +22,8 @@ cmake.build-type = "Release"
 build.verbose = true
 build.tool-args = ["-j8"]
 
-# CMake definitions to optimize compilation
+# CMake definitions to optimize compilation and find Homebrew packages
 [tool.scikit-build.cmake.define]
 CMAKE_BUILD_PARALLEL_LEVEL = "8"
+CMAKE_PREFIX_PATH = {env = "CMAKE_PREFIX_PATH"}
+OpenMP_ROOT = {env = "OpenMP_ROOT"}

packages/leann-core/pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "leann-core"
-version = "0.2.6"
+version = "0.3.4"
 description = "Core API and plugin system for LEANN"
 readme = "README.md"
 requires-python = ">=3.9"
@@ -31,8 +31,10 @@ dependencies = [
     "PyPDF2>=3.0.0",
     "pymupdf>=1.23.0",
     "pdfplumber>=0.10.0",
-    "mlx>=0.26.3; sys_platform == 'darwin'",
-    "mlx-lm>=0.26.0; sys_platform == 'darwin'",
+    "nbconvert>=7.0.0",  # For .ipynb file support
+    "gitignore-parser>=0.1.12",  # For proper .gitignore handling
+    "mlx>=0.26.3; sys_platform == 'darwin' and platform_machine == 'arm64'",
+    "mlx-lm>=0.26.0; sys_platform == 'darwin' and platform_machine == 'arm64'",
 ]
 
 [project.optional-dependencies]

packages/leann-core/src/leann/api.py

@@ -6,18 +6,22 @@ with the correct, original embedding logic from the user's reference code.
 import json
 import logging
 import pickle
+import re
+import subprocess
 import time
 import warnings
 from dataclasses import dataclass, field
 from pathlib import Path
-from typing import Any, Literal
+from typing import Any, Literal, Optional, Union
 
 import numpy as np
+from leann_backend_hnsw.convert_to_csr import prune_hnsw_embeddings_inplace
 
 from leann.interface import LeannBackendSearcherInterface
 
 from .chat import get_llm
 from .interface import LeannBackendFactoryInterface
+from .metadata_filter import MetadataFilterEngine
 from .registry import BACKEND_REGISTRY
 
 logger = logging.getLogger(__name__)
@@ -33,7 +37,7 @@ def compute_embeddings(
     model_name: str,
     mode: str = "sentence-transformers",
     use_server: bool = True,
-    port: int | None = None,
+    port: Optional[int] = None,
     is_build=False,
 ) -> np.ndarray:
     """
@@ -46,6 +50,7 @@ def compute_embeddings(
             - "sentence-transformers": Use sentence-transformers library (default)
             - "mlx": Use MLX backend for Apple Silicon
             - "openai": Use OpenAI embedding API
+            - "gemini": Use Google Gemini embedding API
         use_server: Whether to use embedding server (True for search, False for build)
 
     Returns:
@@ -115,54 +120,180 @@ class SearchResult:
 
 
 class PassageManager:
-    def __init__(self, passage_sources: list[dict[str, Any]]):
-        self.offset_maps = {}
-        self.passage_files = {}
-        self.global_offset_map = {}  # Combined map for fast lookup
+    def __init__(
+        self, passage_sources: list[dict[str, Any]], metadata_file_path: Optional[str] = None
+    ):
+        self.offset_maps: dict[str, dict[str, int]] = {}
+        self.passage_files: dict[str, str] = {}
+        # Avoid materializing a single gigantic global map to reduce memory
+        # footprint on very large corpora (e.g., 60M+ passages). Instead, keep
+        # per-shard maps and do a lightweight per-shard lookup on demand.
+        self._total_count: int = 0
+        self.filter_engine = MetadataFilterEngine()  # Initialize filter engine
+
+        # Derive index base name for standard sibling fallbacks, e.g., <index_name>.passages.*
+        index_name_base = None
+        if metadata_file_path:
+            meta_name = Path(metadata_file_path).name
+            if meta_name.endswith(".meta.json"):
+                index_name_base = meta_name[: -len(".meta.json")]
 
         for source in passage_sources:
             assert source["type"] == "jsonl", "only jsonl is supported"
-            passage_file = source["path"]
-            index_file = source["index_path"]  # .idx file
+            passage_file = source.get("path", "")
+            index_file = source.get("index_path", "")  # .idx file
 
-            # Fix path resolution for Colab and other environments
-            if not Path(index_file).is_absolute():
-                # If relative path, try to resolve it properly
-                index_file = str(Path(index_file).resolve())
+            # Fix path resolution - relative paths should be relative to metadata file directory
+            def _resolve_candidates(
+                primary: str,
+                relative_key: str,
+                default_name: Optional[str],
+                source_dict: dict[str, Any],
+            ) -> list[Path]:
+                """
+                Build an ordered list of candidate paths. For relative paths specified in
+                metadata, prefer resolution relative to the metadata file directory first,
+                then fall back to CWD-based resolution, and finally to conventional
+                sibling defaults (e.g., <index_base>.passages.idx / .jsonl).
+                """
+                candidates: list[Path] = []
+                # 1) Primary path
+                if primary:
+                    p = Path(primary)
+                    if p.is_absolute():
+                        candidates.append(p)
+                    else:
+                        # Prefer metadata-relative resolution for relative paths
+                        if metadata_file_path:
+                            candidates.append(Path(metadata_file_path).parent / p)
+                        # Also consider CWD-relative as a fallback for legacy layouts
+                        candidates.append(Path.cwd() / p)
+                # 2) metadata-relative explicit relative key (if present)
+                if metadata_file_path and source_dict.get(relative_key):
+                    candidates.append(Path(metadata_file_path).parent / source_dict[relative_key])
+                # 3) metadata-relative standard sibling filename
+                if metadata_file_path and default_name:
+                    candidates.append(Path(metadata_file_path).parent / default_name)
+                return candidates
+
+            # Build candidate lists and pick first existing; otherwise keep last candidate for error message
+            idx_default = f"{index_name_base}.passages.idx" if index_name_base else None
+            idx_candidates = _resolve_candidates(
+                index_file, "index_path_relative", idx_default, source
+            )
+            pas_default = f"{index_name_base}.passages.jsonl" if index_name_base else None
+            pas_candidates = _resolve_candidates(passage_file, "path_relative", pas_default, source)
+
+            def _pick_existing(cands: list[Path]) -> str:
+                for c in cands:
+                    if c.exists():
+                        return str(c.resolve())
+                # Fallback to last candidate (best guess) even if not exists; will error below
+                return str(cands[-1].resolve()) if cands else ""
+
+            index_file = _pick_existing(idx_candidates)
+            passage_file = _pick_existing(pas_candidates)
 
             if not Path(index_file).exists():
                 raise FileNotFoundError(f"Passage index file not found: {index_file}")
 
             with open(index_file, "rb") as f:
-                offset_map = pickle.load(f)
+                offset_map: dict[str, int] = pickle.load(f)
                 self.offset_maps[passage_file] = offset_map
                 self.passage_files[passage_file] = passage_file
-
-                # Build global map for O(1) lookup
-                for passage_id, offset in offset_map.items():
-                    self.global_offset_map[passage_id] = (passage_file, offset)
+                self._total_count += len(offset_map)
 
     def get_passage(self, passage_id: str) -> dict[str, Any]:
-        if passage_id in self.global_offset_map:
-            passage_file, offset = self.global_offset_map[passage_id]
-            # Lazy file opening - only open when needed
-            with open(passage_file, encoding="utf-8") as f:
-                f.seek(offset)
-                return json.loads(f.readline())
+        # Fast path: check each shard map (there are typically few shards).
+        # This avoids building a massive combined dict while keeping lookups
+        # bounded by the number of shards.
+        for passage_file, offset_map in self.offset_maps.items():
+            try:
+                offset = offset_map[passage_id]
+                with open(passage_file, encoding="utf-8") as f:
+                    f.seek(offset)
+                    return json.loads(f.readline())
+            except KeyError:
+                continue
         raise KeyError(f"Passage ID not found: {passage_id}")
 
+    def filter_search_results(
+        self,
+        search_results: list[SearchResult],
+        metadata_filters: Optional[dict[str, dict[str, Union[str, int, float, bool, list]]]],
+    ) -> list[SearchResult]:
+        """
+        Apply metadata filters to search results.
+
+        Args:
+            search_results: List of SearchResult objects
+            metadata_filters: Filter specifications to apply
+
+        Returns:
+            Filtered list of SearchResult objects
+        """
+        if not metadata_filters:
+            return search_results
+
+        logger.debug(f"Applying metadata filters to {len(search_results)} results")
+
+        # Convert SearchResult objects to dictionaries for the filter engine
+        result_dicts = []
+        for result in search_results:
+            result_dicts.append(
+                {
+                    "id": result.id,
+                    "score": result.score,
+                    "text": result.text,
+                    "metadata": result.metadata,
+                }
+            )
+
+        # Apply filters using the filter engine
+        filtered_dicts = self.filter_engine.apply_filters(result_dicts, metadata_filters)
+
+        # Convert back to SearchResult objects
+        filtered_results = []
+        for result_dict in filtered_dicts:
+            filtered_results.append(
+                SearchResult(
+                    id=result_dict["id"],
+                    score=result_dict["score"],
+                    text=result_dict["text"],
+                    metadata=result_dict["metadata"],
+                )
+            )
+
+        logger.debug(f"Filtered results: {len(filtered_results)} remaining")
+        return filtered_results
+
+    def __len__(self) -> int:
+        return self._total_count
+
 
 class LeannBuilder:
     def __init__(
         self,
         backend_name: str,
         embedding_model: str = "facebook/contriever",
-        dimensions: int | None = None,
+        dimensions: Optional[int] = None,
         embedding_mode: str = "sentence-transformers",
         **backend_kwargs,
     ):
         self.backend_name = backend_name
-        backend_factory: LeannBackendFactoryInterface | None = BACKEND_REGISTRY.get(backend_name)
+        # Normalize incompatible combinations early (for consistent metadata)
+        if backend_name == "hnsw":
+            is_recompute = backend_kwargs.get("is_recompute", True)
+            is_compact = backend_kwargs.get("is_compact", True)
+            if is_recompute is False and is_compact is True:
+                warnings.warn(
+                    "HNSW with is_recompute=False requires non-compact storage. Forcing is_compact=False.",
+                    UserWarning,
+                    stacklevel=2,
+                )
+                backend_kwargs["is_compact"] = False
+
+        backend_factory: Optional[LeannBackendFactoryInterface] = BACKEND_REGISTRY.get(backend_name)
         if backend_factory is None:
             raise ValueError(f"Backend '{backend_name}' not found or not registered.")
         self.backend_factory = backend_factory
@@ -242,7 +373,7 @@ class LeannBuilder:
         self.backend_kwargs = backend_kwargs
         self.chunks: list[dict[str, Any]] = []
 
-    def add_text(self, text: str, metadata: dict[str, Any] | None = None):
+    def add_text(self, text: str, metadata: Optional[dict[str, Any]] = None):
         if metadata is None:
             metadata = {}
         passage_id = metadata.get("id", str(len(self.chunks)))
@@ -252,6 +383,23 @@ class LeannBuilder:
     def build_index(self, index_path: str):
         if not self.chunks:
             raise ValueError("No chunks added.")
+
+        # Filter out invalid/empty text chunks early to keep passage and embedding counts aligned
+        valid_chunks: list[dict[str, Any]] = []
+        skipped = 0
+        for chunk in self.chunks:
+            text = chunk.get("text", "")
+            if isinstance(text, str) and text.strip():
+                valid_chunks.append(chunk)
+            else:
+                skipped += 1
+        if skipped > 0:
+            print(
+                f"Warning: Skipping {skipped} empty/invalid text chunk(s). Processing {len(valid_chunks)} valid chunks"
+            )
+            self.chunks = valid_chunks
+            if not self.chunks:
+                raise ValueError("All provided chunks are empty or invalid. Nothing to index.")
         if self.dimensions is None:
             self.dimensions = len(
                 compute_embeddings(
@@ -314,8 +462,12 @@ class LeannBuilder:
             "passage_sources": [
                 {
                     "type": "jsonl",
-                    "path": str(passages_file),
-                    "index_path": str(offset_file),
+                    # Preserve existing relative file names (backward-compatible)
+                    "path": passages_file.name,
+                    "index_path": offset_file.name,
+                    # Add optional redundant relative keys for remote build portability (non-breaking)
+                    "path_relative": passages_file.name,
+                    "index_path_relative": offset_file.name,
                 }
             ],
         }
@@ -325,9 +477,7 @@ class LeannBuilder:
             is_compact = self.backend_kwargs.get("is_compact", True)
             is_recompute = self.backend_kwargs.get("is_recompute", True)
             meta_data["is_compact"] = is_compact
-            meta_data["is_pruned"] = (
-                is_compact and is_recompute
-            )  # Pruned only if compact and recompute
+            meta_data["is_pruned"] = bool(is_recompute)
         with open(leann_meta_path, "w", encoding="utf-8") as f:
             json.dump(meta_data, f, indent=2)
 
@@ -430,8 +580,12 @@ class LeannBuilder:
             "passage_sources": [
                 {
                     "type": "jsonl",
-                    "path": str(passages_file),
-                    "index_path": str(offset_file),
+                    # Preserve existing relative file names (backward-compatible)
+                    "path": passages_file.name,
+                    "index_path": offset_file.name,
+                    # Add optional redundant relative keys for remote build portability (non-breaking)
+                    "path_relative": passages_file.name,
+                    "index_path_relative": offset_file.name,
                 }
             ],
             "built_from_precomputed_embeddings": True,
@@ -443,13 +597,157 @@ class LeannBuilder:
             is_compact = self.backend_kwargs.get("is_compact", True)
             is_recompute = self.backend_kwargs.get("is_recompute", True)
             meta_data["is_compact"] = is_compact
-            meta_data["is_pruned"] = is_compact and is_recompute
+            meta_data["is_pruned"] = bool(is_recompute)
 
         with open(leann_meta_path, "w", encoding="utf-8") as f:
             json.dump(meta_data, f, indent=2)
 
         logger.info(f"Index built successfully from precomputed embeddings: {index_path}")
 
+    def update_index(self, index_path: str):
+        """Append new passages and vectors to an existing HNSW index."""
+        if not self.chunks:
+            raise ValueError("No new chunks provided for update.")
+
+        path = Path(index_path)
+        index_dir = path.parent
+        index_name = path.name
+        index_prefix = path.stem
+
+        meta_path = index_dir / f"{index_name}.meta.json"
+        passages_file = index_dir / f"{index_name}.passages.jsonl"
+        offset_file = index_dir / f"{index_name}.passages.idx"
+        index_file = index_dir / f"{index_prefix}.index"
+
+        if not meta_path.exists() or not passages_file.exists() or not offset_file.exists():
+            raise FileNotFoundError("Index metadata or passage files are missing; cannot update.")
+        if not index_file.exists():
+            raise FileNotFoundError(f"HNSW index file not found: {index_file}")
+
+        with open(meta_path, encoding="utf-8") as f:
+            meta = json.load(f)
+        backend_name = meta.get("backend_name")
+        if backend_name != self.backend_name:
+            raise ValueError(
+                f"Index was built with backend '{backend_name}', cannot update with '{self.backend_name}'."
+            )
+
+        meta_backend_kwargs = meta.get("backend_kwargs", {})
+        index_is_compact = meta.get("is_compact", meta_backend_kwargs.get("is_compact", True))
+        if index_is_compact:
+            raise ValueError(
+                "Compact HNSW indices do not support in-place updates. Rebuild required."
+            )
+
+        distance_metric = meta_backend_kwargs.get(
+            "distance_metric", self.backend_kwargs.get("distance_metric", "mips")
+        ).lower()
+        needs_recompute = bool(
+            meta.get("is_pruned")
+            or meta_backend_kwargs.get("is_recompute")
+            or self.backend_kwargs.get("is_recompute")
+        )
+
+        with open(offset_file, "rb") as f:
+            offset_map: dict[str, int] = pickle.load(f)
+        existing_ids = set(offset_map.keys())
+
+        valid_chunks: list[dict[str, Any]] = []
+        for chunk in self.chunks:
+            text = chunk.get("text", "")
+            if not isinstance(text, str) or not text.strip():
+                continue
+            metadata = chunk.setdefault("metadata", {})
+            passage_id = chunk.get("id") or metadata.get("id")
+            if passage_id and passage_id in existing_ids:
+                raise ValueError(f"Passage ID '{passage_id}' already exists in the index.")
+            valid_chunks.append(chunk)
+
+        if not valid_chunks:
+            raise ValueError("No valid chunks to append.")
+
+        texts_to_embed = [chunk["text"] for chunk in valid_chunks]
+        embeddings = compute_embeddings(
+            texts_to_embed,
+            self.embedding_model,
+            self.embedding_mode,
+            use_server=False,
+            is_build=True,
+        )
+
+        embedding_dim = embeddings.shape[1]
+        expected_dim = meta.get("dimensions")
+        if expected_dim is not None and expected_dim != embedding_dim:
+            raise ValueError(
+                f"Dimension mismatch during update: existing index uses {expected_dim}, got {embedding_dim}."
+            )
+
+        from leann_backend_hnsw import faiss  # type: ignore
+
+        embeddings = np.ascontiguousarray(embeddings, dtype=np.float32)
+        if distance_metric == "cosine":
+            norms = np.linalg.norm(embeddings, axis=1, keepdims=True)
+            norms[norms == 0] = 1
+            embeddings = embeddings / norms
+
+        index = faiss.read_index(str(index_file))
+        if hasattr(index, "is_recompute"):
+            index.is_recompute = needs_recompute
+        if getattr(index, "storage", None) is None:
+            if index.metric_type == faiss.METRIC_INNER_PRODUCT:
+                storage_index = faiss.IndexFlatIP(index.d)
+            else:
+                storage_index = faiss.IndexFlatL2(index.d)
+            index.storage = storage_index
+            index.own_fields = True
+        if index.d != embedding_dim:
+            raise ValueError(
+                f"Existing index dimension ({index.d}) does not match new embeddings ({embedding_dim})."
+            )
+
+        base_id = index.ntotal
+        for offset, chunk in enumerate(valid_chunks):
+            new_id = str(base_id + offset)
+            chunk.setdefault("metadata", {})["id"] = new_id
+            chunk["id"] = new_id
+
+        index.add(embeddings.shape[0], faiss.swig_ptr(embeddings))
+        faiss.write_index(index, str(index_file))
+
+        with open(passages_file, "a", encoding="utf-8") as f:
+            for chunk in valid_chunks:
+                offset = f.tell()
+                json.dump(
+                    {
+                        "id": chunk["id"],
+                        "text": chunk["text"],
+                        "metadata": chunk.get("metadata", {}),
+                    },
+                    f,
+                    ensure_ascii=False,
+                )
+                f.write("\n")
+                offset_map[chunk["id"]] = offset
+
+        with open(offset_file, "wb") as f:
+            pickle.dump(offset_map, f)
+
+        meta["total_passages"] = len(offset_map)
+        with open(meta_path, "w", encoding="utf-8") as f:
+            json.dump(meta, f, indent=2)
+
+        logger.info(
+            "Appended %d passages to index '%s'. New total: %d",
+            len(valid_chunks),
+            index_path,
+            len(offset_map),
+        )
+
+        self.chunks.clear()
+
+        if needs_recompute:
+            prune_hnsw_embeddings_inplace(str(index_file))
+
 
 class LeannSearcher:
     def __init__(self, index_path: str, enable_warmup: bool = False, **backend_kwargs):
@@ -473,7 +771,12 @@ class LeannSearcher:
         self.embedding_model = self.meta_data["embedding_model"]
         # Support both old and new format
         self.embedding_mode = self.meta_data.get("embedding_mode", "sentence-transformers")
-        self.passage_manager = PassageManager(self.meta_data.get("passage_sources", []))
+        # Delegate portability handling to PassageManager
+        self.passage_manager = PassageManager(
+            self.meta_data.get("passage_sources", []), metadata_file_path=self.meta_path_str
+        )
+        # Preserve backend name for conditional parameter forwarding
+        self.backend_name = backend_name
         backend_factory = BACKEND_REGISTRY.get(backend_name)
         if backend_factory is None:
             raise ValueError(f"Backend '{backend_name}' not found.")
@@ -493,15 +796,49 @@ class LeannSearcher:
         recompute_embeddings: bool = True,
         pruning_strategy: Literal["global", "local", "proportional"] = "global",
         expected_zmq_port: int = 5557,
+        metadata_filters: Optional[dict[str, dict[str, Union[str, int, float, bool, list]]]] = None,
+        batch_size: int = 0,
+        use_grep: bool = False,
         **kwargs,
     ) -> list[SearchResult]:
+        """
+        Search for nearest neighbors with optional metadata filtering.
+
+        Args:
+            query: Text query to search for
+            top_k: Number of nearest neighbors to return
+            complexity: Search complexity/candidate list size, higher = more accurate but slower
+            beam_width: Number of parallel search paths/IO requests per iteration
+            prune_ratio: Ratio of neighbors to prune via approximate distance (0.0-1.0)
+            recompute_embeddings: Whether to fetch fresh embeddings from server vs use stored codes
+            pruning_strategy: Candidate selection strategy - "global" (default), "local", or "proportional"
+            expected_zmq_port: ZMQ port for embedding server communication
+            metadata_filters: Optional filters to apply to search results based on metadata.
+                Format: {"field_name": {"operator": value}}
+                Supported operators:
+                - Comparison: "==", "!=", "<", "<=", ">", ">="
+                - Membership: "in", "not_in"
+                - String: "contains", "starts_with", "ends_with"
+                Example: {"chapter": {"<=": 5}, "tags": {"in": ["fiction", "drama"]}}
+            **kwargs: Backend-specific parameters
+
+        Returns:
+            List of SearchResult objects with text, metadata, and similarity scores
+        """
+        # Handle grep search
+        if use_grep:
+            return self._grep_search(query, top_k)
+
         logger.info("🔍 LeannSearcher.search() called:")
         logger.info(f"  Query: '{query}'")
         logger.info(f"  Top_k: {top_k}")
+        logger.info(f"  Metadata filters: {metadata_filters}")
         logger.info(f"  Additional kwargs: {kwargs}")
 
         # Smart top_k detection and adjustment
-        total_docs = len(self.passage_manager.global_offset_map)
+        # Use PassageManager length (sum of shard sizes) to avoid
+        # depending on a massive combined map
+        total_docs = len(self.passage_manager)
         original_top_k = top_k
         if top_k > total_docs:
             top_k = total_docs
@@ -530,31 +867,41 @@ class LeannSearcher:
             use_server_if_available=recompute_embeddings,
             zmq_port=zmq_port,
         )
-        # logger.info(f"  Generated embedding shape: {query_embedding.shape}")
-        time.time() - start_time
-        # logger.info(f"  Embedding time: {embedding_time} seconds")
+        logger.info(f"  Generated embedding shape: {query_embedding.shape}")
+        embedding_time = time.time() - start_time
+        logger.info(f"  Embedding time: {embedding_time} seconds")
 
         start_time = time.time()
+        backend_search_kwargs: dict[str, Any] = {
+            "complexity": complexity,
+            "beam_width": beam_width,
+            "prune_ratio": prune_ratio,
+            "recompute_embeddings": recompute_embeddings,
+            "pruning_strategy": pruning_strategy,
+            "zmq_port": zmq_port,
+        }
+        # Only HNSW supports batching; forward conditionally
+        if self.backend_name == "hnsw":
+            backend_search_kwargs["batch_size"] = batch_size
+
+        # Merge any extra kwargs last
+        backend_search_kwargs.update(kwargs)
+
         results = self.backend_impl.search(
             query_embedding,
             top_k,
-            complexity=complexity,
-            beam_width=beam_width,
-            prune_ratio=prune_ratio,
-            recompute_embeddings=recompute_embeddings,
-            pruning_strategy=pruning_strategy,
-            zmq_port=zmq_port,
-            **kwargs,
+            **backend_search_kwargs,
         )
-        time.time() - start_time
-        # logger.info(f"  Search time: {search_time} seconds")
+        search_time = time.time() - start_time
+        logger.info(f"  Search time in search() LEANN searcher: {search_time} seconds")
         logger.info(f"  Backend returned: labels={len(results.get('labels', [[]])[0])} results")
 
         enriched_results = []
         if "labels" in results and "distances" in results:
             logger.info(f"  Processing {len(results['labels'][0])} passage IDs:")
+            # Python 3.9 does not support zip(strict=...); lengths are expected to match
             for i, (string_id, dist) in enumerate(
-                zip(results["labels"][0], results["distances"][0], strict=False)
+                zip(results["labels"][0], results["distances"][0])
             ):
                 try:
                     passage_data = self.passage_manager.get_passage(string_id)
@@ -580,23 +927,154 @@ class LeannSearcher:
                     )
                 except KeyError:
                     RED = "\033[91m"
+                    RESET = "\033[0m"
                     logger.error(
                         f"   {RED}✗{RESET} [{i + 1:2d}] ID: '{string_id}' -> {RED}ERROR: Passage not found!{RESET}"
                     )
 
+        # Apply metadata filters if specified
+        if metadata_filters:
+            logger.info(f"  🔍 Applying metadata filters: {metadata_filters}")
+            enriched_results = self.passage_manager.filter_search_results(
+                enriched_results, metadata_filters
+            )
+
+        # Define color codes outside the loop for final message
+        GREEN = "\033[92m"
+        RESET = "\033[0m"
         logger.info(f"  {GREEN}✓ Final enriched results: {len(enriched_results)} passages{RESET}")
         return enriched_results
 
+    def _find_jsonl_file(self) -> Optional[str]:
+        """Find the .jsonl file containing raw passages for grep search"""
+        index_path = Path(self.meta_path_str).parent
+        potential_files = [
+            index_path / "documents.leann.passages.jsonl",
+            index_path.parent / "documents.leann.passages.jsonl",
+        ]
+
+        for file_path in potential_files:
+            if file_path.exists():
+                return str(file_path)
+        return None
+
+    def _grep_search(self, query: str, top_k: int = 5) -> list[SearchResult]:
+        """Perform grep-based search on raw passages"""
+        jsonl_file = self._find_jsonl_file()
+        if not jsonl_file:
+            raise FileNotFoundError("No .jsonl passages file found for grep search")
+
+        try:
+            cmd = ["grep", "-i", "-n", query, jsonl_file]
+            result = subprocess.run(cmd, capture_output=True, text=True, check=False)
+
+            if result.returncode == 1:
+                return []
+            elif result.returncode != 0:
+                raise RuntimeError(f"Grep failed: {result.stderr}")
+
+            matches = []
+            for line in result.stdout.strip().split("\n"):
+                if not line:
+                    continue
+                parts = line.split(":", 1)
+                if len(parts) != 2:
+                    continue
+
+                try:
+                    data = json.loads(parts[1])
+                    text = data.get("text", "")
+                    score = text.lower().count(query.lower())
+
+                    matches.append(
+                        SearchResult(
+                            id=data.get("id", parts[0]),
+                            text=text,
+                            metadata=data.get("metadata", {}),
+                            score=float(score),
+                        )
+                    )
+                except json.JSONDecodeError:
+                    continue
+
+            matches.sort(key=lambda x: x.score, reverse=True)
+            return matches[:top_k]
+
+        except FileNotFoundError:
+            raise RuntimeError(
+                "grep command not found. Please install grep or use semantic search."
+            )
+
+    def _python_regex_search(self, query: str, top_k: int = 5) -> list[SearchResult]:
+        """Fallback regex search"""
+        jsonl_file = self._find_jsonl_file()
+        if not jsonl_file:
+            raise FileNotFoundError("No .jsonl file found")
+
+        pattern = re.compile(re.escape(query), re.IGNORECASE)
+        matches = []
+
+        with open(jsonl_file, encoding="utf-8") as f:
+            for line_num, line in enumerate(f, 1):
+                if pattern.search(line):
+                    try:
+                        data = json.loads(line.strip())
+                        matches.append(
+                            SearchResult(
+                                id=data.get("id", str(line_num)),
+                                text=data.get("text", ""),
+                                metadata=data.get("metadata", {}),
+                                score=float(len(pattern.findall(data.get("text", "")))),
+                            )
+                        )
+                    except json.JSONDecodeError:
+                        continue
+
+        matches.sort(key=lambda x: x.score, reverse=True)
+        return matches[:top_k]
+
+    def cleanup(self):
+        """Explicitly cleanup embedding server resources.
+        This method should be called after you're done using the searcher,
+        especially in test environments or batch processing scenarios.
+        """
+        backend = getattr(self.backend_impl, "embedding_server_manager", None)
+        if backend is not None:
+            backend.stop_server()
+
+    # Enable automatic cleanup patterns
+    def __enter__(self):
+        return self
+
+    def __exit__(self, exc_type, exc, tb):
+        try:
+            self.cleanup()
+        except Exception:
+            pass
+
+    def __del__(self):
+        try:
+            self.cleanup()
+        except Exception:
+            # Avoid noisy errors during interpreter shutdown
+            pass
+
 
 class LeannChat:
     def __init__(
         self,
         index_path: str,
-        llm_config: dict[str, Any] | None = None,
+        llm_config: Optional[dict[str, Any]] = None,
         enable_warmup: bool = False,
+        searcher: Optional[LeannSearcher] = None,
         **kwargs,
     ):
-        self.searcher = LeannSearcher(index_path, enable_warmup=enable_warmup, **kwargs)
+        if searcher is None:
+            self.searcher = LeannSearcher(index_path, enable_warmup=enable_warmup, **kwargs)
+            self._owns_searcher = True
+        else:
+            self.searcher = searcher
+            self._owns_searcher = False
         self.llm = get_llm(llm_config)
 
     def ask(
@@ -608,8 +1086,11 @@ class LeannChat:
         prune_ratio: float = 0.0,
         recompute_embeddings: bool = True,
         pruning_strategy: Literal["global", "local", "proportional"] = "global",
-        llm_kwargs: dict[str, Any] | None = None,
+        llm_kwargs: Optional[dict[str, Any]] = None,
         expected_zmq_port: int = 5557,
+        metadata_filters: Optional[dict[str, dict[str, Union[str, int, float, bool, list]]]] = None,
+        batch_size: int = 0,
+        use_grep: bool = False,
         **search_kwargs,
     ):
         if llm_kwargs is None:
@@ -624,10 +1105,12 @@ class LeannChat:
             recompute_embeddings=recompute_embeddings,
             pruning_strategy=pruning_strategy,
             expected_zmq_port=expected_zmq_port,
+            metadata_filters=metadata_filters,
+            batch_size=batch_size,
             **search_kwargs,
         )
         search_time = time.time() - search_time
-        # logger.info(f"  Search time: {search_time} seconds")
+        logger.info(f"  Search time: {search_time} seconds")
         context = "\n\n".join([r.text for r in results])
         prompt = (
             "Here is some retrieved context that might help answer your question:\n\n"
@@ -656,3 +1139,30 @@ class LeannChat:
             except (KeyboardInterrupt, EOFError):
                 print("\nGoodbye!")
                 break
+
+    def cleanup(self):
+        """Explicitly cleanup embedding server resources.
+
+        This method should be called after you're done using the chat interface,
+        especially in test environments or batch processing scenarios.
+        """
+        # Only stop the embedding server if this LeannChat instance created the searcher.
+        # When a shared searcher is passed in, avoid shutting down the server to enable reuse.
+        if getattr(self, "_owns_searcher", False) and hasattr(self.searcher, "cleanup"):
+            self.searcher.cleanup()
+
+    # Enable automatic cleanup patterns
+    def __enter__(self):
+        return self
+
+    def __exit__(self, exc_type, exc, tb):
+        try:
+            self.cleanup()
+        except Exception:
+            pass
+
+    def __del__(self):
+        try:
+            self.cleanup()
+        except Exception:
+            pass

packages/leann-core/src/leann/chat.py

@@ -8,7 +8,7 @@ import difflib
 import logging
 import os
 from abc import ABC, abstractmethod
-from typing import Any
+from typing import Any, Optional
 
 import torch
 
@@ -311,7 +311,7 @@ def search_hf_models(query: str, limit: int = 10) -> list[str]:
 
 def validate_model_and_suggest(
     model_name: str, llm_type: str, host: str = "http://localhost:11434"
-) -> str | None:
+) -> Optional[str]:
     """Validate model name and provide suggestions if invalid"""
     if llm_type == "ollama":
         available_models = check_ollama_models(host)
@@ -422,7 +422,6 @@ class LLMInterface(ABC):
                 top_k=10,
                 complexity=64,
                 beam_width=8,
-                USE_DEFERRED_FETCH=True,
                 skip_search_reorder=True,
                 recompute_beighbor_embeddings=True,
                 dedup_node_dis=True,
@@ -434,7 +433,6 @@ class LLMInterface(ABC):
         Supported kwargs:
             - complexity (int): Search complexity parameter (default: 32)
             - beam_width (int): Beam width for search (default: 4)
-            - USE_DEFERRED_FETCH (bool): Enable deferred fetch mode (default: False)
             - skip_search_reorder (bool): Skip search reorder step (default: False)
             - recompute_beighbor_embeddings (bool): Enable ZMQ embedding server for neighbor recomputation (default: False)
             - dedup_node_dis (bool): Deduplicate nodes by distance (default: False)
@@ -682,10 +680,64 @@ class HFChat(LLMInterface):
         return response.strip()
 
 
+class GeminiChat(LLMInterface):
+    """LLM interface for Google Gemini models."""
+
+    def __init__(self, model: str = "gemini-2.5-flash", api_key: Optional[str] = None):
+        self.model = model
+        self.api_key = api_key or os.getenv("GEMINI_API_KEY")
+
+        if not self.api_key:
+            raise ValueError(
+                "Gemini API key is required. Set GEMINI_API_KEY environment variable or pass api_key parameter."
+            )
+
+        logger.info(f"Initializing Gemini Chat with model='{model}'")
+
+        try:
+            import google.genai as genai
+
+            self.client = genai.Client(api_key=self.api_key)
+        except ImportError:
+            raise ImportError(
+                "The 'google-genai' library is required for Gemini models. Please install it with 'uv pip install google-genai'."
+            )
+
+    def ask(self, prompt: str, **kwargs) -> str:
+        logger.info(f"Sending request to Gemini with model {self.model}")
+
+        try:
+            from google.genai.types import GenerateContentConfig
+
+            generation_config = GenerateContentConfig(
+                temperature=kwargs.get("temperature", 0.7),
+                max_output_tokens=kwargs.get("max_tokens", 1000),
+            )
+
+            # Handle top_p parameter
+            if "top_p" in kwargs:
+                generation_config.top_p = kwargs["top_p"]
+
+            response = self.client.models.generate_content(
+                model=self.model,
+                contents=prompt,
+                config=generation_config,
+            )
+            # Handle potential None response text
+            response_text = response.text
+            if response_text is None:
+                logger.warning("Gemini returned None response text")
+                return ""
+            return response_text.strip()
+        except Exception as e:
+            logger.error(f"Error communicating with Gemini: {e}")
+            return f"Error: Could not get a response from Gemini. Details: {e}"
+
+
 class OpenAIChat(LLMInterface):
     """LLM interface for OpenAI models."""
 
-    def __init__(self, model: str = "gpt-4o", api_key: str | None = None):
+    def __init__(self, model: str = "gpt-4o", api_key: Optional[str] = None):
         self.model = model
         self.api_key = api_key or os.getenv("OPENAI_API_KEY")
 
@@ -761,7 +813,7 @@ class SimulatedChat(LLMInterface):
         return "This is a simulated answer from the LLM based on the retrieved context."
 
 
-def get_llm(llm_config: dict[str, Any] | None = None) -> LLMInterface:
+def get_llm(llm_config: Optional[dict[str, Any]] = None) -> LLMInterface:
     """
     Factory function to get an LLM interface based on configuration.
 
@@ -795,6 +847,8 @@ def get_llm(llm_config: dict[str, Any] | None = None) -> LLMInterface:
         return HFChat(model_name=model or "deepseek-ai/deepseek-llm-7b-chat")
     elif llm_type == "openai":
         return OpenAIChat(model=model or "gpt-4o", api_key=llm_config.get("api_key"))
+    elif llm_type == "gemini":
+        return GeminiChat(model=model or "gemini-2.5-flash", api_key=llm_config.get("api_key"))
     elif llm_type == "simulated":
         return SimulatedChat()
     else:

packages/leann-core/src/leann/chunking_utils.py

@@ -0,0 +1,220 @@
+"""
+Enhanced chunking utilities with AST-aware code chunking support.
+Packaged within leann-core so installed wheels can import it reliably.
+"""
+
+import logging
+from pathlib import Path
+from typing import Optional
+
+from llama_index.core.node_parser import SentenceSplitter
+
+logger = logging.getLogger(__name__)
+
+# Code file extensions supported by astchunk
+CODE_EXTENSIONS = {
+    ".py": "python",
+    ".java": "java",
+    ".cs": "csharp",
+    ".ts": "typescript",
+    ".tsx": "typescript",
+    ".js": "typescript",
+    ".jsx": "typescript",
+}
+
+
+def detect_code_files(documents, code_extensions=None) -> tuple[list, list]:
+    """Separate documents into code files and regular text files."""
+    if code_extensions is None:
+        code_extensions = CODE_EXTENSIONS
+
+    code_docs = []
+    text_docs = []
+
+    for doc in documents:
+        file_path = doc.metadata.get("file_path", "") or doc.metadata.get("file_name", "")
+        if file_path:
+            file_ext = Path(file_path).suffix.lower()
+            if file_ext in code_extensions:
+                doc.metadata["language"] = code_extensions[file_ext]
+                doc.metadata["is_code"] = True
+                code_docs.append(doc)
+            else:
+                doc.metadata["is_code"] = False
+                text_docs.append(doc)
+        else:
+            doc.metadata["is_code"] = False
+            text_docs.append(doc)
+
+    logger.info(f"Detected {len(code_docs)} code files and {len(text_docs)} text files")
+    return code_docs, text_docs
+
+
+def get_language_from_extension(file_path: str) -> Optional[str]:
+    """Return language string from a filename/extension using CODE_EXTENSIONS."""
+    ext = Path(file_path).suffix.lower()
+    return CODE_EXTENSIONS.get(ext)
+
+
+def create_ast_chunks(
+    documents,
+    max_chunk_size: int = 512,
+    chunk_overlap: int = 64,
+    metadata_template: str = "default",
+) -> list[str]:
+    """Create AST-aware chunks from code documents using astchunk.
+
+    Falls back to traditional chunking if astchunk is unavailable.
+    """
+    try:
+        from astchunk import ASTChunkBuilder  # optional dependency
+    except ImportError as e:
+        logger.error(f"astchunk not available: {e}")
+        logger.info("Falling back to traditional chunking for code files")
+        return create_traditional_chunks(documents, max_chunk_size, chunk_overlap)
+
+    all_chunks = []
+    for doc in documents:
+        language = doc.metadata.get("language")
+        if not language:
+            logger.warning("No language detected; falling back to traditional chunking")
+            all_chunks.extend(create_traditional_chunks([doc], max_chunk_size, chunk_overlap))
+            continue
+
+        try:
+            configs = {
+                "max_chunk_size": max_chunk_size,
+                "language": language,
+                "metadata_template": metadata_template,
+                "chunk_overlap": chunk_overlap if chunk_overlap > 0 else 0,
+            }
+
+            repo_metadata = {
+                "file_path": doc.metadata.get("file_path", ""),
+                "file_name": doc.metadata.get("file_name", ""),
+                "creation_date": doc.metadata.get("creation_date", ""),
+                "last_modified_date": doc.metadata.get("last_modified_date", ""),
+            }
+            configs["repo_level_metadata"] = repo_metadata
+
+            chunk_builder = ASTChunkBuilder(**configs)
+            code_content = doc.get_content()
+            if not code_content or not code_content.strip():
+                logger.warning("Empty code content, skipping")
+                continue
+
+            chunks = chunk_builder.chunkify(code_content)
+            for chunk in chunks:
+                if hasattr(chunk, "text"):
+                    chunk_text = chunk.text
+                elif isinstance(chunk, dict) and "text" in chunk:
+                    chunk_text = chunk["text"]
+                elif isinstance(chunk, str):
+                    chunk_text = chunk
+                else:
+                    chunk_text = str(chunk)
+
+                if chunk_text and chunk_text.strip():
+                    all_chunks.append(chunk_text.strip())
+
+            logger.info(
+                f"Created {len(chunks)} AST chunks from {language} file: {doc.metadata.get('file_name', 'unknown')}"
+            )
+        except Exception as e:
+            logger.warning(f"AST chunking failed for {language} file: {e}")
+            logger.info("Falling back to traditional chunking")
+            all_chunks.extend(create_traditional_chunks([doc], max_chunk_size, chunk_overlap))
+
+    return all_chunks
+
+
+def create_traditional_chunks(
+    documents, chunk_size: int = 256, chunk_overlap: int = 128
+) -> list[str]:
+    """Create traditional text chunks using LlamaIndex SentenceSplitter."""
+    if chunk_size <= 0:
+        logger.warning(f"Invalid chunk_size={chunk_size}, using default value of 256")
+        chunk_size = 256
+    if chunk_overlap < 0:
+        chunk_overlap = 0
+    if chunk_overlap >= chunk_size:
+        chunk_overlap = chunk_size // 2
+
+    node_parser = SentenceSplitter(
+        chunk_size=chunk_size,
+        chunk_overlap=chunk_overlap,
+        separator=" ",
+        paragraph_separator="\n\n",
+    )
+
+    all_texts = []
+    for doc in documents:
+        try:
+            nodes = node_parser.get_nodes_from_documents([doc])
+            if nodes:
+                all_texts.extend(node.get_content() for node in nodes)
+        except Exception as e:
+            logger.error(f"Traditional chunking failed for document: {e}")
+            content = doc.get_content()
+            if content and content.strip():
+                all_texts.append(content.strip())
+
+    return all_texts
+
+
+def create_text_chunks(
+    documents,
+    chunk_size: int = 256,
+    chunk_overlap: int = 128,
+    use_ast_chunking: bool = False,
+    ast_chunk_size: int = 512,
+    ast_chunk_overlap: int = 64,
+    code_file_extensions: Optional[list[str]] = None,
+    ast_fallback_traditional: bool = True,
+) -> list[str]:
+    """Create text chunks from documents with optional AST support for code files."""
+    if not documents:
+        logger.warning("No documents provided for chunking")
+        return []
+
+    local_code_extensions = CODE_EXTENSIONS.copy()
+    if code_file_extensions:
+        ext_mapping = {
+            ".py": "python",
+            ".java": "java",
+            ".cs": "c_sharp",
+            ".ts": "typescript",
+            ".tsx": "typescript",
+        }
+        for ext in code_file_extensions:
+            if ext.lower() not in local_code_extensions:
+                if ext.lower() in ext_mapping:
+                    local_code_extensions[ext.lower()] = ext_mapping[ext.lower()]
+                else:
+                    logger.warning(f"Unsupported extension {ext}, will use traditional chunking")
+
+    all_chunks = []
+    if use_ast_chunking:
+        code_docs, text_docs = detect_code_files(documents, local_code_extensions)
+        if code_docs:
+            try:
+                all_chunks.extend(
+                    create_ast_chunks(
+                        code_docs, max_chunk_size=ast_chunk_size, chunk_overlap=ast_chunk_overlap
+                    )
+                )
+            except Exception as e:
+                logger.error(f"AST chunking failed: {e}")
+                if ast_fallback_traditional:
+                    all_chunks.extend(
+                        create_traditional_chunks(code_docs, chunk_size, chunk_overlap)
+                    )
+                else:
+                    raise
+        if text_docs:
+            all_chunks.extend(create_traditional_chunks(text_docs, chunk_size, chunk_overlap))
+    else:
+        all_chunks = create_traditional_chunks(documents, chunk_size, chunk_overlap)
+
+    logger.info(f"Total chunks created: {len(all_chunks)}")
+    return all_chunks

packages/leann-core/src/leann/embedding_compute.py

@@ -6,7 +6,7 @@ Preserves all optimization parameters to ensure performance
 
 import logging
 import os
-from concurrent.futures import ThreadPoolExecutor, as_completed
+import time
 from typing import Any
 
 import numpy as np
@@ -29,6 +29,8 @@ def compute_embeddings(
     is_build: bool = False,
     batch_size: int = 32,
     adaptive_optimization: bool = True,
+    manual_tokenize: bool = False,
+    max_length: int = 512,
 ) -> np.ndarray:
     """
     Unified embedding computation entry point
@@ -51,6 +53,8 @@ def compute_embeddings(
             is_build=is_build,
             batch_size=batch_size,
             adaptive_optimization=adaptive_optimization,
+            manual_tokenize=manual_tokenize,
+            max_length=max_length,
         )
     elif mode == "openai":
         return compute_embeddings_openai(texts, model_name)
@@ -58,6 +62,8 @@ def compute_embeddings(
         return compute_embeddings_mlx(texts, model_name)
     elif mode == "ollama":
         return compute_embeddings_ollama(texts, model_name, is_build=is_build)
+    elif mode == "gemini":
+        return compute_embeddings_gemini(texts, model_name, is_build=is_build)
     else:
         raise ValueError(f"Unsupported embedding mode: {mode}")
 
@@ -70,6 +76,8 @@ def compute_embeddings_sentence_transformers(
     batch_size: int = 32,
     is_build: bool = False,
     adaptive_optimization: bool = True,
+    manual_tokenize: bool = False,
+    max_length: int = 512,
 ) -> np.ndarray:
     """
     Compute embeddings using SentenceTransformer with model caching and adaptive optimization
@@ -213,20 +221,130 @@ def compute_embeddings_sentence_transformers(
         logger.info(f"Model cached: {cache_key}")
 
     # Compute embeddings with optimized inference mode
-    logger.info(f"Starting embedding computation... (batch_size: {batch_size})")
+    logger.info(
+        f"Starting embedding computation... (batch_size: {batch_size}, manual_tokenize={manual_tokenize})"
+    )
 
-    # Use torch.inference_mode for optimal performance
-    with torch.inference_mode():
-        embeddings = model.encode(
-            texts,
-            batch_size=batch_size,
-            show_progress_bar=is_build,  # Don't show progress bar in server environment
-            convert_to_numpy=True,
-            normalize_embeddings=False,
-            device=device,
-        )
+    start_time = time.time()
+    if not manual_tokenize:
+        # Use SentenceTransformer's optimized encode path (default)
+        with torch.inference_mode():
+            embeddings = model.encode(
+                texts,
+                batch_size=batch_size,
+                show_progress_bar=is_build,  # Don't show progress bar in server environment
+                convert_to_numpy=True,
+                normalize_embeddings=False,
+                device=device,
+            )
+        # Synchronize if CUDA to measure accurate wall time
+        try:
+            if torch.cuda.is_available():
+                torch.cuda.synchronize()
+        except Exception:
+            pass
+    else:
+        # Manual tokenization + forward pass using HF AutoTokenizer/AutoModel
+        try:
+            from transformers import AutoModel, AutoTokenizer  # type: ignore
+        except Exception as e:
+            raise ImportError(f"transformers is required for manual_tokenize=True: {e}")
 
+        # Cache tokenizer and model
+        tok_cache_key = f"hf_tokenizer_{model_name}"
+        mdl_cache_key = f"hf_model_{model_name}_{device}_{use_fp16}"
+        if tok_cache_key in _model_cache and mdl_cache_key in _model_cache:
+            hf_tokenizer = _model_cache[tok_cache_key]
+            hf_model = _model_cache[mdl_cache_key]
+            logger.info("Using cached HF tokenizer/model for manual path")
+        else:
+            logger.info("Loading HF tokenizer/model for manual tokenization path")
+            hf_tokenizer = AutoTokenizer.from_pretrained(model_name, use_fast=True)
+            torch_dtype = torch.float16 if (use_fp16 and device == "cuda") else torch.float32
+            hf_model = AutoModel.from_pretrained(model_name, torch_dtype=torch_dtype)
+            hf_model.to(device)
+            hf_model.eval()
+            # Optional compile on supported devices
+            if device in ["cuda", "mps"]:
+                try:
+                    hf_model = torch.compile(hf_model, mode="reduce-overhead", dynamic=True)  # type: ignore
+                except Exception:
+                    pass
+            _model_cache[tok_cache_key] = hf_tokenizer
+            _model_cache[mdl_cache_key] = hf_model
+
+        all_embeddings: list[np.ndarray] = []
+        # Progress bar when building or for large inputs
+        show_progress = is_build or len(texts) > 32
+        try:
+            if show_progress:
+                from tqdm import tqdm  # type: ignore
+
+                batch_iter = tqdm(
+                    range(0, len(texts), batch_size),
+                    desc="Embedding (manual)",
+                    unit="batch",
+                )
+            else:
+                batch_iter = range(0, len(texts), batch_size)
+        except Exception:
+            batch_iter = range(0, len(texts), batch_size)
+
+        start_time_manual = time.time()
+        with torch.inference_mode():
+            for start_index in batch_iter:
+                end_index = min(start_index + batch_size, len(texts))
+                batch_texts = texts[start_index:end_index]
+                tokenize_start_time = time.time()
+                inputs = hf_tokenizer(
+                    batch_texts,
+                    padding=True,
+                    truncation=True,
+                    max_length=max_length,
+                    return_tensors="pt",
+                )
+                tokenize_end_time = time.time()
+                logger.info(
+                    f"Tokenize time taken: {tokenize_end_time - tokenize_start_time} seconds"
+                )
+                # Print shapes of all input tensors for debugging
+                for k, v in inputs.items():
+                    print(f"inputs[{k!r}] shape: {getattr(v, 'shape', type(v))}")
+                to_device_start_time = time.time()
+                inputs = {k: v.to(device) for k, v in inputs.items()}
+                to_device_end_time = time.time()
+                logger.info(
+                    f"To device time taken: {to_device_end_time - to_device_start_time} seconds"
+                )
+                forward_start_time = time.time()
+                outputs = hf_model(**inputs)
+                forward_end_time = time.time()
+                logger.info(f"Forward time taken: {forward_end_time - forward_start_time} seconds")
+                last_hidden_state = outputs.last_hidden_state  # (B, L, H)
+                attention_mask = inputs.get("attention_mask")
+                if attention_mask is None:
+                    # Fallback: assume all tokens are valid
+                    pooled = last_hidden_state.mean(dim=1)
+                else:
+                    mask = attention_mask.unsqueeze(-1).to(last_hidden_state.dtype)
+                    masked = last_hidden_state * mask
+                    lengths = mask.sum(dim=1).clamp(min=1)
+                    pooled = masked.sum(dim=1) / lengths
+                # Move to CPU float32
+                batch_embeddings = pooled.detach().to("cpu").float().numpy()
+                all_embeddings.append(batch_embeddings)
+
+        embeddings = np.vstack(all_embeddings).astype(np.float32, copy=False)
+        try:
+            if torch.cuda.is_available():
+                torch.cuda.synchronize()
+        except Exception:
+            pass
+        end_time = time.time()
+        logger.info(f"Manual tokenize time taken: {end_time - start_time_manual} seconds")
+    end_time = time.time()
     logger.info(f"Generated {len(embeddings)} embeddings, dimension: {embeddings.shape[1]}")
+    logger.info(f"Time taken: {end_time - start_time} seconds")
 
     # Validate results
     if np.isnan(embeddings).any() or np.isinf(embeddings).any():
@@ -245,6 +363,16 @@ def compute_embeddings_openai(texts: list[str], model_name: str) -> np.ndarray:
     except ImportError as e:
         raise ImportError(f"OpenAI package not installed: {e}")
 
+    # Validate input list
+    if not texts:
+        raise ValueError("Cannot compute embeddings for empty text list")
+    # Extra validation: abort early if any item is empty/whitespace
+    invalid_count = sum(1 for t in texts if not isinstance(t, str) or not t.strip())
+    if invalid_count > 0:
+        raise ValueError(
+            f"Found {invalid_count} empty/invalid text(s) in input. Upstream should filter before calling OpenAI."
+        )
+
     api_key = os.getenv("OPENAI_API_KEY")
     if not api_key:
         raise RuntimeError("OPENAI_API_KEY environment variable not set")
@@ -264,8 +392,16 @@ def compute_embeddings_openai(texts: list[str], model_name: str) -> np.ndarray:
     print(f"len of texts: {len(texts)}")
 
     # OpenAI has limits on batch size and input length
-    max_batch_size = 1000  # Conservative batch size
+    max_batch_size = 800  # Conservative batch size because the token limit is 300K
     all_embeddings = []
+    # get the avg len of texts
+    avg_len = sum(len(text) for text in texts) / len(texts)
+    print(f"avg len of texts: {avg_len}")
+    # if avg len is less than 1000, use the max batch size
+    if avg_len > 300:
+        max_batch_size = 500
+
+    # if avg len is less than 1000, use the max batch size
 
     try:
         from tqdm import tqdm
@@ -374,7 +510,9 @@ def compute_embeddings_ollama(
     texts: list[str], model_name: str, is_build: bool = False, host: str = "http://localhost:11434"
 ) -> np.ndarray:
     """
-    Compute embeddings using Ollama API.
+    Compute embeddings using Ollama API with simplified batch processing.
+
+    Uses batch size of 32 for MPS/CPU and 128 for CUDA to optimize performance.
 
     Args:
         texts: List of texts to compute embeddings for
@@ -438,12 +576,19 @@ def compute_embeddings_ollama(
             if any(emb in base_name for emb in ["embed", "bge", "minilm", "e5"]):
                 embedding_models.append(model)
 
-        # Check if model exists (handle versioned names)
-        model_found = any(
-            model_name == name.split(":")[0] or model_name == name for name in model_names
-        )
+        # Check if model exists (handle versioned names) and resolve to full name
+        resolved_model_name = None
+        for name in model_names:
+            # Exact match
+            if model_name == name:
+                resolved_model_name = name
+                break
+            # Match without version tag (use the versioned name)
+            elif model_name == name.split(":")[0]:
+                resolved_model_name = name
+                break
 
-        if not model_found:
+        if not resolved_model_name:
             error_msg = f"❌ Model '{model_name}' not found in local Ollama.\n\n"
 
             # Suggest pulling the model
@@ -465,6 +610,11 @@ def compute_embeddings_ollama(
             error_msg += "\n📚 Browse more: https://ollama.com/library"
             raise ValueError(error_msg)
 
+        # Use the resolved model name for all subsequent operations
+        if resolved_model_name != model_name:
+            logger.info(f"Resolved model name '{model_name}' to '{resolved_model_name}'")
+        model_name = resolved_model_name
+
         # Verify the model supports embeddings by testing it
         try:
             test_response = requests.post(
@@ -485,138 +635,148 @@ def compute_embeddings_ollama(
     except requests.exceptions.RequestException as e:
         logger.warning(f"Could not verify model existence: {e}")
 
-    # Process embeddings with optimized concurrent processing
-    import requests
+    # Determine batch size based on device availability
+    # Check for CUDA/MPS availability using torch if available
+    batch_size = 32  # Default for MPS/CPU
+    try:
+        import torch
 
-    def get_single_embedding(text_idx_tuple):
-        """Helper function to get embedding for a single text."""
-        text, idx = text_idx_tuple
-        max_retries = 3
-        retry_count = 0
+        if torch.cuda.is_available():
+            batch_size = 128  # CUDA gets larger batch size
+        elif hasattr(torch.backends, "mps") and torch.backends.mps.is_available():
+            batch_size = 32  # MPS gets smaller batch size
+    except ImportError:
+        # If torch is not available, use conservative batch size
+        batch_size = 32
 
-        # Truncate very long texts to avoid API issues
-        truncated_text = text[:8000] if len(text) > 8000 else text
+    logger.info(f"Using batch size: {batch_size}")
 
-        while retry_count < max_retries:
-            try:
-                response = requests.post(
-                    f"{host}/api/embeddings",
-                    json={"model": model_name, "prompt": truncated_text},
-                    timeout=30,
-                )
-                response.raise_for_status()
+    def get_batch_embeddings(batch_texts):
+        """Get embeddings for a batch of texts."""
+        all_embeddings = []
+        failed_indices = []
 
-                result = response.json()
-                embedding = result.get("embedding")
+        for i, text in enumerate(batch_texts):
+            max_retries = 3
+            retry_count = 0
 
-                if embedding is None:
-                    raise ValueError(f"No embedding returned for text {idx}")
-
-                return idx, embedding
-
-            except requests.exceptions.Timeout:
-                retry_count += 1
-                if retry_count >= max_retries:
-                    logger.warning(f"Timeout for text {idx} after {max_retries} retries")
-                    return idx, None
-
-            except Exception as e:
-                if retry_count >= max_retries - 1:
-                    logger.error(f"Failed to get embedding for text {idx}: {e}")
-                    return idx, None
-                retry_count += 1
-
-        return idx, None
-
-    # Determine if we should use concurrent processing
-    use_concurrent = (
-        len(texts) > 5 and not is_build
-    )  # Don't use concurrent in build mode to avoid overwhelming
-    max_workers = min(4, len(texts))  # Limit concurrent requests to avoid overwhelming Ollama
-
-    all_embeddings = [None] * len(texts)  # Pre-allocate list to maintain order
-    failed_indices = []
-
-    if use_concurrent:
-        logger.info(
-            f"Using concurrent processing with {max_workers} workers for {len(texts)} texts"
-        )
-
-        with ThreadPoolExecutor(max_workers=max_workers) as executor:
-            # Submit all tasks
-            future_to_idx = {
-                executor.submit(get_single_embedding, (text, idx)): idx
-                for idx, text in enumerate(texts)
-            }
-
-            # Add progress bar for concurrent processing
-            try:
-                if is_build or len(texts) > 10:
-                    from tqdm import tqdm
-
-                    futures_iterator = tqdm(
-                        as_completed(future_to_idx),
-                        total=len(texts),
-                        desc="Computing Ollama embeddings",
-                    )
-                else:
-                    futures_iterator = as_completed(future_to_idx)
-            except ImportError:
-                futures_iterator = as_completed(future_to_idx)
-
-            # Collect results as they complete
-            for future in futures_iterator:
+            # Truncate very long texts to avoid API issues
+            truncated_text = text[:8000] if len(text) > 8000 else text
+            while retry_count < max_retries:
                 try:
-                    idx, embedding = future.result()
-                    if embedding is not None:
-                        all_embeddings[idx] = embedding
-                    else:
-                        failed_indices.append(idx)
+                    response = requests.post(
+                        f"{host}/api/embeddings",
+                        json={"model": model_name, "prompt": truncated_text},
+                        timeout=30,
+                    )
+                    response.raise_for_status()
+
+                    result = response.json()
+                    embedding = result.get("embedding")
+
+                    if embedding is None:
+                        raise ValueError(f"No embedding returned for text {i}")
+
+                    if not isinstance(embedding, list) or len(embedding) == 0:
+                        raise ValueError(f"Invalid embedding format for text {i}")
+
+                    all_embeddings.append(embedding)
+                    break
+
+                except requests.exceptions.Timeout:
+                    retry_count += 1
+                    if retry_count >= max_retries:
+                        logger.warning(f"Timeout for text {i} after {max_retries} retries")
+                        failed_indices.append(i)
+                        all_embeddings.append(None)
+                        break
+
                 except Exception as e:
-                    idx = future_to_idx[future]
-                    logger.error(f"Exception for text {idx}: {e}")
-                    failed_indices.append(idx)
+                    retry_count += 1
+                    if retry_count >= max_retries:
+                        logger.error(f"Failed to get embedding for text {i}: {e}")
+                        failed_indices.append(i)
+                        all_embeddings.append(None)
+                        break
+        return all_embeddings, failed_indices
 
+    # Process texts in batches
+    all_embeddings = []
+    all_failed_indices = []
+
+    # Setup progress bar if needed
+    show_progress = is_build or len(texts) > 10
+    try:
+        if show_progress:
+            from tqdm import tqdm
+    except ImportError:
+        show_progress = False
+
+    # Process batches
+    num_batches = (len(texts) + batch_size - 1) // batch_size
+
+    if show_progress:
+        batch_iterator = tqdm(range(num_batches), desc="Computing Ollama embeddings")
     else:
-        # Sequential processing with progress bar
-        show_progress = is_build or len(texts) > 10
+        batch_iterator = range(num_batches)
 
-        try:
-            if show_progress:
-                from tqdm import tqdm
+    for batch_idx in batch_iterator:
+        start_idx = batch_idx * batch_size
+        end_idx = min(start_idx + batch_size, len(texts))
+        batch_texts = texts[start_idx:end_idx]
 
-                iterator = tqdm(
-                    enumerate(texts), total=len(texts), desc="Computing Ollama embeddings"
-                )
-            else:
-                iterator = enumerate(texts)
-        except ImportError:
-            iterator = enumerate(texts)
+        batch_embeddings, batch_failed = get_batch_embeddings(batch_texts)
 
-        for idx, text in iterator:
-            result_idx, embedding = get_single_embedding((text, idx))
-            if embedding is not None:
-                all_embeddings[idx] = embedding
-            else:
-                failed_indices.append(idx)
+        # Adjust failed indices to global indices
+        global_failed = [start_idx + idx for idx in batch_failed]
+        all_failed_indices.extend(global_failed)
+        all_embeddings.extend(batch_embeddings)
 
     # Handle failed embeddings
-    if failed_indices:
-        if len(failed_indices) == len(texts):
+    if all_failed_indices:
+        if len(all_failed_indices) == len(texts):
             raise RuntimeError("Failed to compute any embeddings")
 
-        logger.warning(f"Failed to compute embeddings for {len(failed_indices)}/{len(texts)} texts")
+        logger.warning(
+            f"Failed to compute embeddings for {len(all_failed_indices)}/{len(texts)} texts"
+        )
 
         # Use zero embeddings as fallback for failed ones
         valid_embedding = next((e for e in all_embeddings if e is not None), None)
         if valid_embedding:
             embedding_dim = len(valid_embedding)
-            for idx in failed_indices:
-                all_embeddings[idx] = [0.0] * embedding_dim
+            for i, embedding in enumerate(all_embeddings):
+                if embedding is None:
+                    all_embeddings[i] = [0.0] * embedding_dim
 
-    # Remove None values and convert to numpy array
+    # Remove None values
     all_embeddings = [e for e in all_embeddings if e is not None]
 
+    if not all_embeddings:
+        raise RuntimeError("No valid embeddings were computed")
+
+    # Validate embedding dimensions
+    expected_dim = len(all_embeddings[0])
+    inconsistent_dims = []
+    for i, embedding in enumerate(all_embeddings):
+        if len(embedding) != expected_dim:
+            inconsistent_dims.append((i, len(embedding)))
+
+    if inconsistent_dims:
+        error_msg = f"Ollama returned inconsistent embedding dimensions. Expected {expected_dim}, but got:\n"
+        for idx, dim in inconsistent_dims[:10]:  # Show first 10 inconsistent ones
+            error_msg += f"  - Text {idx}: {dim} dimensions\n"
+        if len(inconsistent_dims) > 10:
+            error_msg += f"  ... and {len(inconsistent_dims) - 10} more\n"
+        error_msg += f"\nThis is likely an Ollama API bug with model '{model_name}'. Please try:\n"
+        error_msg += "1. Restart Ollama service: 'ollama serve'\n"
+        error_msg += f"2. Re-pull the model: 'ollama pull {model_name}'\n"
+        error_msg += (
+            "3. Use sentence-transformers instead: --embedding-mode sentence-transformers\n"
+        )
+        error_msg += "4. Report this issue to Ollama: https://github.com/ollama/ollama/issues"
+        raise ValueError(error_msg)
+
     # Convert to numpy array and normalize
     embeddings = np.array(all_embeddings, dtype=np.float32)
 
@@ -627,3 +787,83 @@ def compute_embeddings_ollama(
     logger.info(f"Generated {len(embeddings)} embeddings, dimension: {embeddings.shape[1]}")
 
     return embeddings
+
+
+def compute_embeddings_gemini(
+    texts: list[str], model_name: str = "text-embedding-004", is_build: bool = False
+) -> np.ndarray:
+    """
+    Compute embeddings using Google Gemini API.
+
+    Args:
+        texts: List of texts to compute embeddings for
+        model_name: Gemini model name (default: "text-embedding-004")
+        is_build: Whether this is a build operation (shows progress bar)
+
+    Returns:
+        Embeddings array, shape: (len(texts), embedding_dim)
+    """
+    try:
+        import os
+
+        import google.genai as genai
+    except ImportError as e:
+        raise ImportError(f"Google GenAI package not installed: {e}")
+
+    api_key = os.getenv("GEMINI_API_KEY")
+    if not api_key:
+        raise RuntimeError("GEMINI_API_KEY environment variable not set")
+
+    # Cache Gemini client
+    cache_key = "gemini_client"
+    if cache_key in _model_cache:
+        client = _model_cache[cache_key]
+    else:
+        client = genai.Client(api_key=api_key)
+        _model_cache[cache_key] = client
+        logger.info("Gemini client cached")
+
+    logger.info(
+        f"Computing embeddings for {len(texts)} texts using Gemini API, model: '{model_name}'"
+    )
+
+    # Gemini supports batch embedding
+    max_batch_size = 100  # Conservative batch size for Gemini
+    all_embeddings = []
+
+    try:
+        from tqdm import tqdm
+
+        total_batches = (len(texts) + max_batch_size - 1) // max_batch_size
+        batch_range = range(0, len(texts), max_batch_size)
+        batch_iterator = tqdm(
+            batch_range, desc="Computing embeddings", unit="batch", total=total_batches
+        )
+    except ImportError:
+        # Fallback when tqdm is not available
+        batch_iterator = range(0, len(texts), max_batch_size)
+
+    for i in batch_iterator:
+        batch_texts = texts[i : i + max_batch_size]
+
+        try:
+            # Use the embed_content method from the new Google GenAI SDK
+            response = client.models.embed_content(
+                model=model_name,
+                contents=batch_texts,
+                config=genai.types.EmbedContentConfig(
+                    task_type="RETRIEVAL_DOCUMENT"  # For document embedding
+                ),
+            )
+
+            # Extract embeddings from response
+            for embedding_data in response.embeddings:
+                all_embeddings.append(embedding_data.values)
+        except Exception as e:
+            logger.error(f"Batch {i} failed: {e}")
+            raise
+
+    embeddings = np.array(all_embeddings, dtype=np.float32)
+    logger.info(f"Generated {len(embeddings)} embeddings, dimension: {embeddings.shape[1]}")
+
+    return embeddings

packages/leann-core/src/leann/embedding_server_manager.py

@@ -6,8 +6,9 @@ import subprocess
 import sys
 import time
 from pathlib import Path
+from typing import Optional
 
-import psutil
+# Lightweight, self-contained server manager with no cross-process inspection
 
 # Set up logging based on environment variable
 LOG_LEVEL = os.getenv("LEANN_LOG_LEVEL", "WARNING").upper()
@@ -42,130 +43,7 @@ def _check_port(port: int) -> bool:
         return s.connect_ex(("localhost", port)) == 0
 
 
-def _check_process_matches_config(
-    port: int, expected_model: str, expected_passages_file: str
-) -> bool:
-    """
-    Check if the process using the port matches our expected model and passages file.
-    Returns True if matches, False otherwise.
-    """
-    try:
-        for proc in psutil.process_iter(["pid", "cmdline"]):
-            if not _is_process_listening_on_port(proc, port):
-                continue
-
-            cmdline = proc.info["cmdline"]
-            if not cmdline:
-                continue
-
-            return _check_cmdline_matches_config(
-                cmdline, port, expected_model, expected_passages_file
-            )
-
-        logger.debug(f"No process found listening on port {port}")
-        return False
-
-    except Exception as e:
-        logger.warning(f"Could not check process on port {port}: {e}")
-        return False
-
-
-def _is_process_listening_on_port(proc, port: int) -> bool:
-    """Check if a process is listening on the given port."""
-    try:
-        connections = proc.net_connections()
-        for conn in connections:
-            if conn.laddr.port == port and conn.status == psutil.CONN_LISTEN:
-                return True
-        return False
-    except (psutil.NoSuchProcess, psutil.AccessDenied, psutil.ZombieProcess):
-        return False
-
-
-def _check_cmdline_matches_config(
-    cmdline: list, port: int, expected_model: str, expected_passages_file: str
-) -> bool:
-    """Check if command line matches our expected configuration."""
-    cmdline_str = " ".join(cmdline)
-    logger.debug(f"Found process on port {port}: {cmdline_str}")
-
-    # Check if it's our embedding server
-    is_embedding_server = any(
-        server_type in cmdline_str
-        for server_type in [
-            "embedding_server",
-            "leann_backend_diskann.embedding_server",
-            "leann_backend_hnsw.hnsw_embedding_server",
-        ]
-    )
-
-    if not is_embedding_server:
-        logger.debug(f"Process on port {port} is not our embedding server")
-        return False
-
-    # Check model name
-    model_matches = _check_model_in_cmdline(cmdline, expected_model)
-
-    # Check passages file if provided
-    passages_matches = _check_passages_in_cmdline(cmdline, expected_passages_file)
-
-    result = model_matches and passages_matches
-    logger.debug(
-        f"model_matches: {model_matches}, passages_matches: {passages_matches}, overall: {result}"
-    )
-    return result
-
-
-def _check_model_in_cmdline(cmdline: list, expected_model: str) -> bool:
-    """Check if the command line contains the expected model."""
-    if "--model-name" not in cmdline:
-        return False
-
-    model_idx = cmdline.index("--model-name")
-    if model_idx + 1 >= len(cmdline):
-        return False
-
-    actual_model = cmdline[model_idx + 1]
-    return actual_model == expected_model
-
-
-def _check_passages_in_cmdline(cmdline: list, expected_passages_file: str) -> bool:
-    """Check if the command line contains the expected passages file."""
-    if "--passages-file" not in cmdline:
-        return False  # Expected but not found
-
-    passages_idx = cmdline.index("--passages-file")
-    if passages_idx + 1 >= len(cmdline):
-        return False
-
-    actual_passages = cmdline[passages_idx + 1]
-    expected_path = Path(expected_passages_file).resolve()
-    actual_path = Path(actual_passages).resolve()
-    return actual_path == expected_path
-
-
-def _find_compatible_port_or_next_available(
-    start_port: int, model_name: str, passages_file: str, max_attempts: int = 100
-) -> tuple[int, bool]:
-    """
-    Find a port that either has a compatible server or is available.
-    Returns (port, is_compatible) where is_compatible indicates if we found a matching server.
-    """
-    for port in range(start_port, start_port + max_attempts):
-        if not _check_port(port):
-            # Port is available
-            return port, False
-
-        # Port is in use, check if it's compatible
-        if _check_process_matches_config(port, model_name, passages_file):
-            logger.info(f"Found compatible server on port {port}")
-            return port, True
-        else:
-            logger.info(f"Port {port} has incompatible server, trying next port...")
-
-    raise RuntimeError(
-        f"Could not find compatible or available port in range {start_port}-{start_port + max_attempts}"
-    )
+# Note: All cross-process scanning helpers removed for simplicity
 
 
 class EmbeddingServerManager:
@@ -182,9 +60,18 @@ class EmbeddingServerManager:
                                        e.g., "leann_backend_diskann.embedding_server"
         """
         self.backend_module_name = backend_module_name
-        self.server_process: subprocess.Popen | None = None
-        self.server_port: int | None = None
+        self.server_process: Optional[subprocess.Popen] = None
+        self.server_port: Optional[int] = None
+        # Track last-started config for in-process reuse only
+        self._server_config: Optional[dict] = None
         self._atexit_registered = False
+        # Also register a weakref finalizer to ensure cleanup when manager is GC'ed
+        try:
+            import weakref
+
+            self._finalizer = weakref.finalize(self, self._finalize_process)
+        except Exception:
+            self._finalizer = None
 
     def start_server(
         self,
@@ -194,26 +81,24 @@ class EmbeddingServerManager:
         **kwargs,
     ) -> tuple[bool, int]:
         """Start the embedding server."""
-        passages_file = kwargs.get("passages_file")
+        # passages_file may be present in kwargs for server CLI, but we don't need it here
 
-        # Check if we have a compatible server already running
-        if self._has_compatible_running_server(model_name, passages_file):
-            logger.info("Found compatible running server!")
-            return True, port
+        # If this manager already has a live server, just reuse it
+        if self.server_process and self.server_process.poll() is None and self.server_port:
+            logger.info("Reusing in-process server")
+            return True, self.server_port
 
         # For Colab environment, use a different strategy
         if _is_colab_environment():
             logger.info("Detected Colab environment, using alternative startup strategy")
             return self._start_server_colab(port, model_name, embedding_mode, **kwargs)
 
-        # Find a compatible port or next available
-        actual_port, is_compatible = _find_compatible_port_or_next_available(
-            port, model_name, passages_file
-        )
-
-        if is_compatible:
-            logger.info(f"Found compatible server on port {actual_port}")
-            return True, actual_port
+        # Always pick a fresh available port
+        try:
+            actual_port = _get_available_port(port)
+        except RuntimeError:
+            logger.error("No available ports found")
+            return False, port
 
         # Start a new server
         return self._start_new_server(actual_port, model_name, embedding_mode, **kwargs)
@@ -246,17 +131,7 @@ class EmbeddingServerManager:
             logger.error(f"Failed to start embedding server in Colab: {e}")
             return False, actual_port
 
-    def _has_compatible_running_server(self, model_name: str, passages_file: str) -> bool:
-        """Check if we have a compatible running server."""
-        if not (self.server_process and self.server_process.poll() is None and self.server_port):
-            return False
-
-        if _check_process_matches_config(self.server_port, model_name, passages_file):
-            logger.info(f"Existing server process (PID {self.server_process.pid}) is compatible")
-            return True
-
-        logger.info("Existing server process is incompatible. Should start a new server.")
-        return False
+    # Note: No compatibility check needed; manager is per-searcher and configs are stable per instance
 
     def _start_new_server(
         self, port: int, model_name: str, embedding_mode: str, **kwargs
@@ -303,22 +178,62 @@ class EmbeddingServerManager:
         project_root = Path(__file__).parent.parent.parent.parent.parent
         logger.info(f"Command: {' '.join(command)}")
 
-        # Let server output go directly to console
-        # The server will respect LEANN_LOG_LEVEL environment variable
+        # In CI environment, redirect stdout to avoid buffer deadlock but keep stderr for debugging
+        # Embedding servers use many print statements that can fill stdout buffers
+        is_ci = os.environ.get("CI") == "true"
+        if is_ci:
+            stdout_target = subprocess.DEVNULL
+            stderr_target = None  # Keep stderr for error debugging in CI
+            logger.info(
+                "CI environment detected, redirecting embedding server stdout to DEVNULL, keeping stderr"
+            )
+        else:
+            stdout_target = None  # Direct to console for visible logs
+            stderr_target = None  # Direct to console for visible logs
+
+        # Start embedding server subprocess
+        logger.info(f"Starting server process with command: {' '.join(command)}")
         self.server_process = subprocess.Popen(
             command,
             cwd=project_root,
-            stdout=None,  # Direct to console
-            stderr=None,  # Direct to console
+            stdout=stdout_target,
+            stderr=stderr_target,
         )
         self.server_port = port
+        # Record config for in-process reuse
+        try:
+            self._server_config = {
+                "model_name": command[command.index("--model-name") + 1]
+                if "--model-name" in command
+                else "",
+                "passages_file": command[command.index("--passages-file") + 1]
+                if "--passages-file" in command
+                else "",
+                "embedding_mode": command[command.index("--embedding-mode") + 1]
+                if "--embedding-mode" in command
+                else "sentence-transformers",
+            }
+        except Exception:
+            self._server_config = {
+                "model_name": "",
+                "passages_file": "",
+                "embedding_mode": "sentence-transformers",
+            }
         logger.info(f"Server process started with PID: {self.server_process.pid}")
 
         # Register atexit callback only when we actually start a process
         if not self._atexit_registered:
-            # Use a lambda to avoid issues with bound methods
-            atexit.register(lambda: self.stop_server() if self.server_process else None)
+            # Always attempt best-effort finalize at interpreter exit
+            atexit.register(self._finalize_process)
             self._atexit_registered = True
+        # Touch finalizer so it knows there is a live process
+        if getattr(self, "_finalizer", None) is not None and not self._finalizer.alive:
+            try:
+                import weakref
+
+                self._finalizer = weakref.finalize(self, self._finalize_process)
+            except Exception:
+                pass
 
     def _wait_for_server_ready(self, port: int) -> tuple[bool, int]:
         """Wait for the server to be ready."""
@@ -343,24 +258,35 @@ class EmbeddingServerManager:
         if not self.server_process:
             return
 
-        if self.server_process.poll() is not None:
+        if self.server_process and self.server_process.poll() is not None:
             # Process already terminated
             self.server_process = None
+            self.server_port = None
+            self._server_config = None
             return
 
         logger.info(
             f"Terminating server process (PID: {self.server_process.pid}) for backend {self.backend_module_name}..."
         )
-        self.server_process.terminate()
+
+        # Use simple termination first; if the server installed signal handlers,
+        # it will exit cleanly. Otherwise escalate to kill after a short wait.
+        try:
+            self.server_process.terminate()
+        except Exception:
+            pass
 
         try:
-            self.server_process.wait(timeout=3)
-            logger.info(f"Server process {self.server_process.pid} terminated.")
+            self.server_process.wait(timeout=5)  # Give more time for graceful shutdown
+            logger.info(f"Server process {self.server_process.pid} terminated gracefully.")
         except subprocess.TimeoutExpired:
             logger.warning(
-                f"Server process {self.server_process.pid} did not terminate gracefully within 3 seconds, killing it."
+                f"Server process {self.server_process.pid} did not terminate within 5 seconds, force killing..."
             )
-            self.server_process.kill()
+            try:
+                self.server_process.kill()
+            except Exception:
+                pass
             try:
                 self.server_process.wait(timeout=2)
                 logger.info(f"Server process {self.server_process.pid} killed successfully.")
@@ -368,15 +294,33 @@ class EmbeddingServerManager:
                 logger.error(
                     f"Failed to kill server process {self.server_process.pid} - it may be hung"
                 )
-                # Don't hang indefinitely
 
-        # Clean up process resources to prevent resource tracker warnings
+        # Clean up process resources with timeout to avoid CI hang
         try:
-            self.server_process.wait()  # Ensure process is fully cleaned up
+            # Use shorter timeout in CI environments
+            is_ci = os.environ.get("CI") == "true"
+            timeout = 3 if is_ci else 10
+            self.server_process.wait(timeout=timeout)
+            logger.info(f"Server process {self.server_process.pid} cleanup completed")
+        except subprocess.TimeoutExpired:
+            logger.warning(f"Process cleanup timeout after {timeout}s, proceeding anyway")
+        except Exception as e:
+            logger.warning(f"Error during process cleanup: {e}")
+        finally:
+            self.server_process = None
+            self.server_port = None
+            self._server_config = None
+
+    def _finalize_process(self) -> None:
+        """Best-effort cleanup used by weakref.finalize/atexit."""
+        try:
+            self.stop_server()
         except Exception:
             pass
 
-        self.server_process = None
+    def _adopt_existing_server(self, *args, **kwargs) -> None:
+        # Removed: cross-process adoption no longer supported
+        return
 
     def _launch_server_process_colab(self, command: list, port: int) -> None:
         """Launch the server process with Colab-specific settings."""
@@ -392,10 +336,16 @@ class EmbeddingServerManager:
         self.server_port = port
         logger.info(f"Colab server process started with PID: {self.server_process.pid}")
 
-        # Register atexit callback
+        # Register atexit callback (unified)
         if not self._atexit_registered:
-            atexit.register(lambda: self.stop_server() if self.server_process else None)
+            atexit.register(self._finalize_process)
             self._atexit_registered = True
+        # Record config for in-process reuse is best-effort in Colab mode
+        self._server_config = {
+            "model_name": "",
+            "passages_file": "",
+            "embedding_mode": "sentence-transformers",
+        }
 
     def _wait_for_server_ready_colab(self, port: int) -> tuple[bool, int]:
         """Wait for the server to be ready with Colab-specific timeout."""

packages/leann-core/src/leann/interface.py

@@ -1,5 +1,5 @@
 from abc import ABC, abstractmethod
-from typing import Any, Literal
+from typing import Any, Literal, Optional
 
 import numpy as np
 
@@ -34,7 +34,9 @@ class LeannBackendSearcherInterface(ABC):
         pass
 
     @abstractmethod
-    def _ensure_server_running(self, passages_source_file: str, port: int | None, **kwargs) -> int:
+    def _ensure_server_running(
+        self, passages_source_file: str, port: Optional[int], **kwargs
+    ) -> int:
         """Ensure server is running"""
         pass
 
@@ -48,7 +50,7 @@ class LeannBackendSearcherInterface(ABC):
         prune_ratio: float = 0.0,
         recompute_embeddings: bool = False,
         pruning_strategy: Literal["global", "local", "proportional"] = "global",
-        zmq_port: int | None = None,
+        zmq_port: Optional[int] = None,
         **kwargs,
     ) -> dict[str, Any]:
         """Search for nearest neighbors
@@ -74,7 +76,7 @@ class LeannBackendSearcherInterface(ABC):
         self,
         query: str,
         use_server_if_available: bool = True,
-        zmq_port: int | None = None,
+        zmq_port: Optional[int] = None,
     ) -> np.ndarray:
         """Compute embedding for a query string
 

packages/leann-core/src/leann/mcp.py

@@ -64,19 +64,6 @@ def handle_request(request):
                             "required": ["index_name", "query"],
                         },
                     },
-                    {
-                        "name": "leann_status",
-                        "description": "📊 Check the health and stats of your code indexes - like a medical checkup for your codebase knowledge!",
-                        "inputSchema": {
-                            "type": "object",
-                            "properties": {
-                                "index_name": {
-                                    "type": "string",
-                                    "description": "Optional: Name of specific index to check. If not provided, shows status of all indexes.",
-                                }
-                            },
-                        },
-                    },
                     {
                         "name": "leann_list",
                         "description": "📋 Show all your indexed codebases - your personal code library! Use this to see what's available for search.",
@@ -107,7 +94,7 @@ def handle_request(request):
                         },
                     }
 
-                # Build simplified command
+                # Build simplified command with non-interactive flag for MCP compatibility
                 cmd = [
                     "leann",
                     "search",
@@ -115,19 +102,10 @@ def handle_request(request):
                     args["query"],
                     f"--top-k={args.get('top_k', 5)}",
                     f"--complexity={args.get('complexity', 32)}",
+                    "--non-interactive",
                 ]
-
                 result = subprocess.run(cmd, capture_output=True, text=True)
 
-            elif tool_name == "leann_status":
-                if args.get("index_name"):
-                    # Check specific index status - for now, we'll use leann list and filter
-                    result = subprocess.run(["leann", "list"], capture_output=True, text=True)
-                    # We could enhance this to show more detailed status per index
-                else:
-                    # Show all indexes status
-                    result = subprocess.run(["leann", "list"], capture_output=True, text=True)
-
             elif tool_name == "leann_list":
                 result = subprocess.run(["leann", "list"], capture_output=True, text=True)
 

packages/leann-core/src/leann/metadata_filter.py

@@ -0,0 +1,240 @@
+"""
+Metadata filtering engine for LEANN search results.
+
+This module provides generic metadata filtering capabilities that can be applied
+to search results from any LEANN backend. The filtering supports various
+operators for different data types including numbers, strings, booleans, and lists.
+"""
+
+import logging
+from typing import Any, Union
+
+logger = logging.getLogger(__name__)
+
+# Type alias for filter specifications
+FilterValue = Union[str, int, float, bool, list]
+FilterSpec = dict[str, FilterValue]
+MetadataFilters = dict[str, FilterSpec]
+
+
+class MetadataFilterEngine:
+    """
+    Engine for evaluating metadata filters against search results.
+
+    Supports various operators for filtering based on metadata fields:
+    - Comparison: ==, !=, <, <=, >, >=
+    - Membership: in, not_in
+    - String operations: contains, starts_with, ends_with
+    - Boolean operations: is_true, is_false
+    """
+
+    def __init__(self):
+        """Initialize the filter engine with supported operators."""
+        self.operators = {
+            "==": self._equals,
+            "!=": self._not_equals,
+            "<": self._less_than,
+            "<=": self._less_than_or_equal,
+            ">": self._greater_than,
+            ">=": self._greater_than_or_equal,
+            "in": self._in,
+            "not_in": self._not_in,
+            "contains": self._contains,
+            "starts_with": self._starts_with,
+            "ends_with": self._ends_with,
+            "is_true": self._is_true,
+            "is_false": self._is_false,
+        }
+
+    def apply_filters(
+        self, search_results: list[dict[str, Any]], metadata_filters: MetadataFilters
+    ) -> list[dict[str, Any]]:
+        """
+        Apply metadata filters to a list of search results.
+
+        Args:
+            search_results: List of result dictionaries, each containing 'metadata' field
+            metadata_filters: Dictionary of filter specifications
+                Format: {"field_name": {"operator": value}}
+
+        Returns:
+            Filtered list of search results
+        """
+        if not metadata_filters:
+            return search_results
+
+        logger.debug(f"Applying filters: {metadata_filters}")
+        logger.debug(f"Input results count: {len(search_results)}")
+
+        filtered_results = []
+        for result in search_results:
+            if self._evaluate_filters(result, metadata_filters):
+                filtered_results.append(result)
+
+        logger.debug(f"Filtered results count: {len(filtered_results)}")
+        return filtered_results
+
+    def _evaluate_filters(self, result: dict[str, Any], filters: MetadataFilters) -> bool:
+        """
+        Evaluate all filters against a single search result.
+
+        All filters must pass (AND logic) for the result to be included.
+
+        Args:
+            result: Full search result dictionary (including metadata, text, etc.)
+            filters: Filter specifications to evaluate
+
+        Returns:
+            True if all filters pass, False otherwise
+        """
+        for field_name, filter_spec in filters.items():
+            if not self._evaluate_field_filter(result, field_name, filter_spec):
+                return False
+        return True
+
+    def _evaluate_field_filter(
+        self, result: dict[str, Any], field_name: str, filter_spec: FilterSpec
+    ) -> bool:
+        """
+        Evaluate a single field filter against a search result.
+
+        Args:
+            result: Full search result dictionary
+            field_name: Name of the field to filter on
+            filter_spec: Filter specification for this field
+
+        Returns:
+            True if the filter passes, False otherwise
+        """
+        # First check top-level fields, then check metadata
+        field_value = result.get(field_name)
+        if field_value is None:
+            # Try to get from metadata if not found at top level
+            metadata = result.get("metadata", {})
+            field_value = metadata.get(field_name)
+
+        # Handle missing fields - they fail all filters except existence checks
+        if field_value is None:
+            logger.debug(f"Field '{field_name}' not found in result or metadata")
+            return False
+
+        # Evaluate each operator in the filter spec
+        for operator, expected_value in filter_spec.items():
+            if operator not in self.operators:
+                logger.warning(f"Unsupported operator: {operator}")
+                return False
+
+            try:
+                if not self.operators[operator](field_value, expected_value):
+                    logger.debug(
+                        f"Filter failed: {field_name} {operator} {expected_value} "
+                        f"(actual: {field_value})"
+                    )
+                    return False
+            except Exception as e:
+                logger.warning(
+                    f"Error evaluating filter {field_name} {operator} {expected_value}: {e}"
+                )
+                return False
+
+        return True
+
+    # Comparison operators
+    def _equals(self, field_value: Any, expected_value: Any) -> bool:
+        """Check if field value equals expected value."""
+        return field_value == expected_value
+
+    def _not_equals(self, field_value: Any, expected_value: Any) -> bool:
+        """Check if field value does not equal expected value."""
+        return field_value != expected_value
+
+    def _less_than(self, field_value: Any, expected_value: Any) -> bool:
+        """Check if field value is less than expected value."""
+        return self._numeric_compare(field_value, expected_value, lambda a, b: a < b)
+
+    def _less_than_or_equal(self, field_value: Any, expected_value: Any) -> bool:
+        """Check if field value is less than or equal to expected value."""
+        return self._numeric_compare(field_value, expected_value, lambda a, b: a <= b)
+
+    def _greater_than(self, field_value: Any, expected_value: Any) -> bool:
+        """Check if field value is greater than expected value."""
+        return self._numeric_compare(field_value, expected_value, lambda a, b: a > b)
+
+    def _greater_than_or_equal(self, field_value: Any, expected_value: Any) -> bool:
+        """Check if field value is greater than or equal to expected value."""
+        return self._numeric_compare(field_value, expected_value, lambda a, b: a >= b)
+
+    # Membership operators
+    def _in(self, field_value: Any, expected_value: Any) -> bool:
+        """Check if field value is in the expected list/collection."""
+        if not isinstance(expected_value, (list, tuple, set)):
+            raise ValueError("'in' operator requires a list, tuple, or set")
+        return field_value in expected_value
+
+    def _not_in(self, field_value: Any, expected_value: Any) -> bool:
+        """Check if field value is not in the expected list/collection."""
+        if not isinstance(expected_value, (list, tuple, set)):
+            raise ValueError("'not_in' operator requires a list, tuple, or set")
+        return field_value not in expected_value
+
+    # String operators
+    def _contains(self, field_value: Any, expected_value: Any) -> bool:
+        """Check if field value contains the expected substring."""
+        field_str = str(field_value)
+        expected_str = str(expected_value)
+        return expected_str in field_str
+
+    def _starts_with(self, field_value: Any, expected_value: Any) -> bool:
+        """Check if field value starts with the expected prefix."""
+        field_str = str(field_value)
+        expected_str = str(expected_value)
+        return field_str.startswith(expected_str)
+
+    def _ends_with(self, field_value: Any, expected_value: Any) -> bool:
+        """Check if field value ends with the expected suffix."""
+        field_str = str(field_value)
+        expected_str = str(expected_value)
+        return field_str.endswith(expected_str)
+
+    # Boolean operators
+    def _is_true(self, field_value: Any, expected_value: Any) -> bool:
+        """Check if field value is truthy."""
+        return bool(field_value)
+
+    def _is_false(self, field_value: Any, expected_value: Any) -> bool:
+        """Check if field value is falsy."""
+        return not bool(field_value)
+
+    # Helper methods
+    def _numeric_compare(self, field_value: Any, expected_value: Any, compare_func) -> bool:
+        """
+        Helper for numeric comparisons with type coercion.
+
+        Args:
+            field_value: Value from metadata
+            expected_value: Value to compare against
+            compare_func: Comparison function to apply
+
+        Returns:
+            Result of comparison
+        """
+        try:
+            # Try to convert both values to numbers for comparison
+            if isinstance(field_value, str) and isinstance(expected_value, str):
+                # String comparison if both are strings
+                return compare_func(field_value, expected_value)
+
+            # Numeric comparison - attempt to convert to float
+            field_num = (
+                float(field_value) if not isinstance(field_value, (int, float)) else field_value
+            )
+            expected_num = (
+                float(expected_value)
+                if not isinstance(expected_value, (int, float))
+                else expected_value
+            )
+
+            return compare_func(field_num, expected_num)
+        except (ValueError, TypeError):
+            # Fall back to string comparison if numeric conversion fails
+            return compare_func(str(field_value), str(expected_value))

packages/leann-core/src/leann/registry.py

@@ -2,11 +2,17 @@
 
 import importlib
 import importlib.metadata
-from typing import TYPE_CHECKING
+import json
+import logging
+from pathlib import Path
+from typing import TYPE_CHECKING, Optional, Union
 
 if TYPE_CHECKING:
     from leann.interface import LeannBackendFactoryInterface
 
+# Set up logger for this module
+logger = logging.getLogger(__name__)
+
 BACKEND_REGISTRY: dict[str, "LeannBackendFactoryInterface"] = {}
 
 
@@ -14,7 +20,7 @@ def register_backend(name: str):
     """A decorator to register a new backend class."""
 
     def decorator(cls):
-        print(f"INFO: Registering backend '{name}'")
+        logger.debug(f"Registering backend '{name}'")
         BACKEND_REGISTRY[name] = cls
         return cls
 
@@ -39,3 +45,54 @@ def autodiscover_backends():
             # print(f"WARN: Could not import backend module '{backend_module_name}': {e}")
             pass
     # print("INFO: Backend auto-discovery finished.")
+
+
+def register_project_directory(project_dir: Optional[Union[str, Path]] = None):
+    """
+    Register a project directory in the global LEANN registry.
+
+    This allows `leann list` to discover indexes created by apps or other tools.
+
+    Args:
+        project_dir: Directory to register. If None, uses current working directory.
+    """
+    if project_dir is None:
+        project_dir = Path.cwd()
+    else:
+        project_dir = Path(project_dir)
+
+    # Only register directories that have some kind of LEANN content
+    # Either .leann/indexes/ (CLI format) or *.leann.meta.json files (apps format)
+    has_cli_indexes = (project_dir / ".leann" / "indexes").exists()
+    has_app_indexes = any(project_dir.rglob("*.leann.meta.json"))
+
+    if not (has_cli_indexes or has_app_indexes):
+        # Don't register if there are no LEANN indexes
+        return
+
+    global_registry = Path.home() / ".leann" / "projects.json"
+    global_registry.parent.mkdir(exist_ok=True)
+
+    project_str = str(project_dir.resolve())
+
+    # Load existing registry
+    projects = []
+    if global_registry.exists():
+        try:
+            with open(global_registry) as f:
+                projects = json.load(f)
+        except Exception:
+            logger.debug("Could not load existing project registry")
+            projects = []
+
+    # Add project if not already present
+    if project_str not in projects:
+        projects.append(project_str)
+
+        # Save updated registry
+        try:
+            with open(global_registry, "w") as f:
+                json.dump(projects, f, indent=2)
+            logger.debug(f"Registered project directory: {project_str}")
+        except Exception as e:
+            logger.warning(f"Could not save project registry: {e}")

packages/leann-core/src/leann/searcher_base.py

@@ -1,7 +1,7 @@
 import json
 from abc import ABC, abstractmethod
 from pathlib import Path
-from typing import Any, Literal
+from typing import Any, Literal, Optional
 
 import numpy as np
 
@@ -169,7 +169,7 @@ class BaseSearcher(LeannBackendSearcherInterface, ABC):
         prune_ratio: float = 0.0,
         recompute_embeddings: bool = False,
         pruning_strategy: Literal["global", "local", "proportional"] = "global",
-        zmq_port: int | None = None,
+        zmq_port: Optional[int] = None,
         **kwargs,
     ) -> dict[str, Any]:
         """

packages/leann-mcp/README.md

@@ -2,29 +2,33 @@
 
 Transform your development workflow with intelligent code assistance using LEANN's semantic search directly in Claude Code.
 
+For agent-facing discovery details, see `llms.txt` in the repository root.
+
 ## Prerequisites
 
-**Step 1:** First, complete the basic LEANN installation following the [📦 Installation guide](../../README.md#installation) in the root README:
+Install LEANN globally for MCP integration (with default backend):
 
 ```bash
-uv venv
-source .venv/bin/activate
-uv pip install leann
+uv tool install leann-core --with leann
 ```
-
-**Step 2:** Install LEANN globally for MCP integration:
-```bash
-uv tool install leann-core
-```
-
-This makes the `leann` command available system-wide, which `leann_mcp` requires.
+This installs the `leann` CLI into an isolated tool environment and includes both backends so `leann build` works out-of-the-box.
 
 ## 🚀 Quick Setup
 
-Add the LEANN MCP server to Claude Code:
+Add the LEANN MCP server to Claude Code. Choose the scope based on how widely you want it available. Below is the command to install it globally; if you prefer a local install, skip this step:
 
 ```bash
-claude mcp add leann-server -- leann_mcp
+# Global (recommended): available in all projects for your user
+claude mcp add --scope user leann-server -- leann_mcp
+```
+
+- `leann-server`: the display name of the MCP server in Claude Code (you can change it).
+- `leann_mcp`: the Python entry point installed with LEANN that starts the MCP server.
+
+Verify it is registered globally:
+
+```bash
+claude mcp list | cat
 ```
 
 ## 🛠️ Available Tools
@@ -33,19 +37,64 @@ Once connected, you'll have access to these powerful semantic search tools in Cl
 
 - **`leann_list`** - List all available indexes across your projects
 - **`leann_search`** - Perform semantic searches across code and documents
-- **`leann_ask`** - Ask natural language questions and get AI-powered answers from your codebase
+
 
 ## 🎯 Quick Start Example
 
 ```bash
+# Add locally if you did not add it globally (current folder only; default if --scope is omitted)
+claude mcp add leann-server -- leann_mcp
+
 # Build an index for your project (change to your actual path)
-leann build my-project --docs ./
+# See the advanced examples below for more ways to configure indexing
+# Set the index name (replace 'my-project' with your own)
+leann build my-project --docs $(git ls-files)
 
 # Start Claude Code
 claude
 ```
 
-**Try this in Claude Code:**
+## 🚀 Advanced Usage Examples to build the index
+
+### Index Entire Git Repository
+```bash
+# Index all tracked files in your Git repository.
+# Note: submodules are currently skipped; we can add them back if needed.
+leann build my-repo --docs $(git ls-files) --embedding-mode sentence-transformers --embedding-model all-MiniLM-L6-v2 --backend hnsw
+
+# Index only tracked Python files from Git.
+leann build my-python-code --docs $(git ls-files "*.py") --embedding-mode sentence-transformers --embedding-model all-MiniLM-L6-v2 --backend hnsw
+
+# If you encounter empty requests caused by empty files (e.g., __init__.py), exclude zero-byte files. Thanks @ww2283 for pointing [that](https://github.com/yichuan-w/LEANN/issues/48) out
+leann build leann-prospec-lig --docs $(find ./src -name "*.py" -not -empty) --embedding-mode openai --embedding-model text-embedding-3-small
+```
+
+### Multiple Directories and Files
+```bash
+# Index multiple directories
+leann build my-codebase --docs ./src ./tests ./docs ./config --embedding-mode sentence-transformers --embedding-model all-MiniLM-L6-v2 --backend hnsw
+
+# Mix files and directories
+leann build my-project --docs ./README.md ./src/ ./package.json ./docs/ --embedding-mode sentence-transformers --embedding-model all-MiniLM-L6-v2 --backend hnsw
+
+# Specific files only
+leann build my-configs --docs ./tsconfig.json ./package.json ./webpack.config.js --embedding-mode sentence-transformers --embedding-model all-MiniLM-L6-v2 --backend hnsw
+```
+
+### Advanced Git Integration
+```bash
+# Index recently modified files
+leann build recent-changes --docs $(git diff --name-only HEAD~10..HEAD) --embedding-mode sentence-transformers --embedding-model all-MiniLM-L6-v2 --backend hnsw
+
+# Index files matching pattern
+leann build frontend --docs $(git ls-files "*.tsx" "*.ts" "*.jsx" "*.js") --embedding-mode sentence-transformers --embedding-model all-MiniLM-L6-v2 --backend hnsw
+
+# Index documentation and config files
+leann build docs-and-configs --docs $(git ls-files "*.md" "*.yml" "*.yaml" "*.json" "*.toml") --embedding-mode sentence-transformers --embedding-model all-MiniLM-L6-v2 --backend hnsw
+```
+
+
+## **Try this in Claude Code:**
 ```
 Help me understand this codebase. List available indexes and search for authentication patterns.
 ```
@@ -54,6 +103,7 @@ Help me understand this codebase. List available indexes and search for authenti
   <img src="../../assets/claude_code_leann.png" alt="LEANN in Claude Code" width="80%">
 </p>
 
+If you see a prompt asking whether to proceed with LEANN, you can now use it in your chat!
 
 ## 🧠 How It Works
 
@@ -89,3 +139,11 @@ To remove LEANN
 ```
 uv pip uninstall leann leann-backend-hnsw leann-core
 ```
+
+To globally remove LEANN (for version update)
+```
+uv tool list | cat
+uv tool uninstall leann-core
+command -v leann || echo "leann gone"
+command -v leann_mcp || echo "leann_mcp gone"
+```

packages/leann/pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "leann"
-version = "0.2.6"
+version = "0.3.4"
 description = "LEANN - The smallest vector index in the world. RAG Everything with LEANN!"
 readme = "README.md"
 requires-python = ">=3.9"

packages/wechat-exporter/__init__.py

@@ -0,0 +1 @@
+__all__ = []

packages/wechat-exporter/main.py

@@ -136,5 +136,9 @@ def export_sqlite(
     connection.commit()
 
 
-if __name__ == "__main__":
+def main():
     app()
+
+
+if __name__ == "__main__":
+    main()

pyproject.toml

@@ -10,11 +10,10 @@ requires-python = ">=3.9"
 dependencies = [
     "leann-core",
     "leann-backend-hnsw",
+    "typer>=0.12.3",
     "numpy>=1.26.0",
     "torch",
     "tqdm",
-    "flask",
-    "flask_compress",
     "datasets>=2.15.0",
     "evaluate",
     "colorama",
@@ -32,7 +31,7 @@ dependencies = [
     "pypdfium2>=4.30.0",
     # LlamaIndex core and readers - updated versions
     "llama-index>=0.12.44",
-    "llama-index-readers-file>=0.4.0",  # Essential for PDF parsing
+    "llama-index-readers-file>=0.4.0", # Essential for PDF parsing
     # "llama-index-readers-docling",  # Requires Python >= 3.10
     # "llama-index-node-parser-docling",  # Requires Python >= 3.10
     "llama-index-vector-stores-faiss>=0.4.0",
@@ -40,9 +39,20 @@ dependencies = [
     # Other dependencies
     "ipykernel==6.29.5",
     "msgpack>=1.1.1",
-    "mlx>=0.26.3; sys_platform == 'darwin'",
-    "mlx-lm>=0.26.0; sys_platform == 'darwin'",
+    "mlx>=0.26.3; sys_platform == 'darwin' and platform_machine == 'arm64'",
+    "mlx-lm>=0.26.0; sys_platform == 'darwin' and platform_machine == 'arm64'",
     "psutil>=5.8.0",
+    "pybind11>=3.0.0",
+    "pathspec>=0.12.1",
+    "nbconvert>=7.16.6",
+    "gitignore-parser>=0.1.12",
+    # AST-aware code chunking dependencies
+    "astchunk>=0.1.0",
+    "tree-sitter>=0.20.0",
+    "tree-sitter-python>=0.20.0",
+    "tree-sitter-java>=0.20.0",
+    "tree-sitter-c-sharp>=0.20.0",
+    "tree-sitter-typescript>=0.20.0",
 ]
 
 [project.optional-dependencies]
@@ -51,7 +61,7 @@ dev = [
     "pytest-cov>=4.0",
     "pytest-xdist>=3.0",  # For parallel test execution
     "black>=23.0",
-    "ruff>=0.1.0",
+    "ruff==0.12.7",  # Fixed version to ensure consistent formatting across all environments
     "matplotlib",
     "huggingface-hub>=0.20.0",
     "pre-commit>=3.5.0",
@@ -61,9 +71,7 @@ test = [
     "pytest>=7.0",
     "pytest-timeout>=2.0",
     "llama-index-core>=0.12.0",
-    "llama-index-readers-file>=0.4.0",
     "python-dotenv>=1.0.0",
-    "sentence-transformers>=2.2.0",
 ]
 
 diskann = [
@@ -80,23 +88,24 @@ documents = [
 
 [tool.setuptools]
 py-modules = []
+packages = ["wechat_exporter"]
+package-dir = { "wechat_exporter" = "packages/wechat-exporter" }
+
+[project.scripts]
+wechat-exporter = "wechat_exporter.main:main"
 
 
 [tool.uv.sources]
 leann-core = { path = "packages/leann-core", editable = true }
 leann-backend-diskann = { path = "packages/leann-backend-diskann", editable = true }
 leann-backend-hnsw = { path = "packages/leann-backend-hnsw", editable = true }
+astchunk = { path = "packages/astchunk-leann", editable = true }
 
 [tool.ruff]
-target-version = "py310"
+target-version = "py39"
 line-length = 100
-extend-exclude = [
-    "third_party",
-    "*.egg-info",
-    "__pycache__",
-    ".git",
-    ".venv",
-]
+extend-exclude = ["third_party"]
+
 
 [tool.ruff.lint]
 select = [
@@ -119,21 +128,12 @@ ignore = [
     "RUF012", # mutable class attributes should be annotated with typing.ClassVar
 ]
 
-[tool.ruff.lint.per-file-ignores]
-"test/**/*.py" = ["E402"]      # module level import not at top of file (common in tests)
-"examples/**/*.py" = ["E402"]  # module level import not at top of file (common in examples)
-
 [tool.ruff.format]
 quote-style = "double"
 indent-style = "space"
 skip-magic-trailing-comma = false
 line-ending = "auto"
 
-[dependency-groups]
-dev = [
-    "ruff>=0.12.4",
-]
-
 [tool.lychee]
 accept = ["200", "403", "429", "503"]
 timeout = 20
@@ -151,7 +151,7 @@ markers = [
     "slow: marks tests as slow (deselect with '-m \"not slow\"')",
     "openai: marks tests that require OpenAI API key",
 ]
-timeout = 600
+timeout = 300  # Reduced from 600s (10min) to 300s (5min) for CI safety
 addopts = [
     "-v",
     "--tb=short",

sky/leann-build.yaml

@@ -0,0 +1,76 @@
+name: leann-build
+
+resources:
+  # Choose a GPU for fast embeddings (examples: L4, A10G, A100). CPU also works but is slower.
+  accelerators: L4:1
+  # Optionally pin a cloud, otherwise SkyPilot will auto-select
+  # cloud: aws
+  disk_size: 100
+
+envs:
+  # Build parameters (override with: sky launch -c leann-gpu sky/leann-build.yaml -e key=value)
+  index_name: my-index
+  docs: ./data
+  backend: hnsw               # hnsw | diskann
+  complexity: 64
+  graph_degree: 32
+  num_threads: 8
+  # Embedding selection
+  embedding_mode: sentence-transformers   # sentence-transformers | openai | mlx | ollama
+  embedding_model: facebook/contriever
+  # Storage/latency knobs
+  recompute: true             # true => selective recomputation (recommended)
+  compact: true               # for HNSW only
+  # Optional pass-through
+  extra_args: ""
+  # Rebuild control
+  force: true
+
+# Sync local paths to the remote VM. Adjust as needed.
+file_mounts:
+  # Example: mount your local data directory used for building
+  ~/leann-data: ${docs}
+
+setup: |
+  set -e
+  # Install uv (package manager)
+  curl -LsSf https://astral.sh/uv/install.sh | sh
+  export PATH="$HOME/.local/bin:$PATH"
+
+  # Ensure modern libstdc++ for FAISS (GLIBCXX >= 3.4.30)
+  sudo apt-get update -y
+  sudo apt-get install -y libstdc++6 libgomp1
+  # Also upgrade conda's libstdc++ in base env (Skypilot images include conda)
+  if command -v conda >/dev/null 2>&1; then
+    conda install -y -n base -c conda-forge libstdcxx-ng
+  fi
+
+  # Install LEANN CLI and backends into the user environment
+  uv pip install --upgrade pip
+  uv pip install leann-core leann-backend-hnsw leann-backend-diskann
+
+run: |
+  export PATH="$HOME/.local/bin:$PATH"
+  # Derive flags from env
+  recompute_flag=""
+  if [ "${recompute}" = "false" ] || [ "${recompute}" = "0" ]; then
+    recompute_flag="--no-recompute"
+  fi
+  force_flag=""
+  if [ "${force}" = "true" ] || [ "${force}" = "1" ]; then
+    force_flag="--force"
+  fi
+
+  # Build command
+  python -m leann.cli build ${index_name} \
+    --docs ~/leann-data \
+    --backend ${backend} \
+    --complexity ${complexity} \
+    --graph-degree ${graph_degree} \
+    --num-threads ${num_threads} \
+    --embedding-mode ${embedding_mode} \
+    --embedding-model ${embedding_model} \
+    ${recompute_flag} ${force_flag} ${extra_args}
+
+  # Print where the index is stored for downstream rsync
+  echo "INDEX_OUT_DIR=~/.leann/indexes/${index_name}"

tests/README.md

@@ -6,10 +6,11 @@ This directory contains automated tests for the LEANN project using pytest.
 
 ### `test_readme_examples.py`
 Tests the examples shown in README.md:
-- The basic example code that users see first
+- The basic example code that users see first (parametrized for both HNSW and DiskANN backends)
 - Import statements work correctly
 - Different backend options (HNSW, DiskANN)
-- Different LLM configuration options
+- Different LLM configuration options (parametrized for both backends)
+- **All main README examples are tested with both HNSW and DiskANN backends using pytest parametrization**
 
 ### `test_basic.py`
 Basic functionality tests that verify:
@@ -25,6 +26,16 @@ Tests the document RAG example functionality:
 - Tests error handling with invalid parameters
 - Verifies that normalized embeddings are detected and cosine distance is used
 
+### `test_diskann_partition.py`
+Tests DiskANN graph partitioning functionality:
+- Tests DiskANN index building without partitioning (baseline)
+- Tests automatic graph partitioning with `is_recompute=True`
+- Verifies that partition files are created and large files are cleaned up for storage saving
+- Tests search functionality with partitioned indices
+- Validates medoid and max_base_norm file generation and usage
+- Includes performance comparison between DiskANN (with partition) and HNSW
+- **Note**: These tests are skipped in CI due to hardware requirements and computation time
+
 ## Running Tests
 
 ### Install test dependencies:
@@ -54,15 +65,23 @@ pytest tests/ -m "not openai"
 
 # Skip slow tests
 pytest tests/ -m "not slow"
+
+# Run DiskANN partition tests (requires local machine, not CI)
+pytest tests/test_diskann_partition.py
 ```
 
 ### Run with specific backend:
 ```bash
 # Test only HNSW backend
 pytest tests/test_basic.py::test_backend_basic[hnsw]
+pytest tests/test_readme_examples.py::test_readme_basic_example[hnsw]
 
 # Test only DiskANN backend
 pytest tests/test_basic.py::test_backend_basic[diskann]
+pytest tests/test_readme_examples.py::test_readme_basic_example[diskann]
+
+# All DiskANN tests (parametrized + specialized partition tests)
+pytest tests/ -k diskann
 ```
 
 ## CI/CD Integration

tests/test_astchunk_integration.py

@@ -0,0 +1,397 @@
+"""
+Test suite for astchunk integration with LEANN.
+Tests AST-aware chunking functionality, language detection, and fallback mechanisms.
+"""
+
+import os
+import subprocess
+import sys
+import tempfile
+from pathlib import Path
+from unittest.mock import patch
+
+import pytest
+
+# Add apps directory to path for imports
+sys.path.insert(0, str(Path(__file__).parent.parent / "apps"))
+
+from typing import Optional
+
+from chunking import (
+    create_ast_chunks,
+    create_text_chunks,
+    create_traditional_chunks,
+    detect_code_files,
+    get_language_from_extension,
+)
+
+
+class MockDocument:
+    """Mock LlamaIndex Document for testing."""
+
+    def __init__(self, content: str, file_path: str = "", metadata: Optional[dict] = None):
+        self.content = content
+        self.metadata = metadata or {}
+        if file_path:
+            self.metadata["file_path"] = file_path
+
+    def get_content(self) -> str:
+        return self.content
+
+
+class TestCodeFileDetection:
+    """Test code file detection and language mapping."""
+
+    def test_detect_code_files_python(self):
+        """Test detection of Python files."""
+        docs = [
+            MockDocument("print('hello')", "/path/to/file.py"),
+            MockDocument("This is text", "/path/to/file.txt"),
+        ]
+
+        code_docs, text_docs = detect_code_files(docs)
+
+        assert len(code_docs) == 1
+        assert len(text_docs) == 1
+        assert code_docs[0].metadata["language"] == "python"
+        assert code_docs[0].metadata["is_code"] is True
+        assert text_docs[0].metadata["is_code"] is False
+
+    def test_detect_code_files_multiple_languages(self):
+        """Test detection of multiple programming languages."""
+        docs = [
+            MockDocument("def func():", "/path/to/script.py"),
+            MockDocument("public class Test {}", "/path/to/Test.java"),
+            MockDocument("interface ITest {}", "/path/to/test.ts"),
+            MockDocument("using System;", "/path/to/Program.cs"),
+            MockDocument("Regular text content", "/path/to/document.txt"),
+        ]
+
+        code_docs, text_docs = detect_code_files(docs)
+
+        assert len(code_docs) == 4
+        assert len(text_docs) == 1
+
+        languages = [doc.metadata["language"] for doc in code_docs]
+        assert "python" in languages
+        assert "java" in languages
+        assert "typescript" in languages
+        assert "csharp" in languages
+
+    def test_detect_code_files_no_file_path(self):
+        """Test handling of documents without file paths."""
+        docs = [
+            MockDocument("some content"),
+            MockDocument("other content", metadata={"some_key": "value"}),
+        ]
+
+        code_docs, text_docs = detect_code_files(docs)
+
+        assert len(code_docs) == 0
+        assert len(text_docs) == 2
+        for doc in text_docs:
+            assert doc.metadata["is_code"] is False
+
+    def test_get_language_from_extension(self):
+        """Test language detection from file extensions."""
+        assert get_language_from_extension("test.py") == "python"
+        assert get_language_from_extension("Test.java") == "java"
+        assert get_language_from_extension("component.tsx") == "typescript"
+        assert get_language_from_extension("Program.cs") == "csharp"
+        assert get_language_from_extension("document.txt") is None
+        assert get_language_from_extension("") is None
+
+
+class TestChunkingFunctions:
+    """Test various chunking functionality."""
+
+    def test_create_traditional_chunks(self):
+        """Test traditional text chunking."""
+        docs = [
+            MockDocument(
+                "This is a test document. It has multiple sentences. We want to test chunking."
+            )
+        ]
+
+        chunks = create_traditional_chunks(docs, chunk_size=50, chunk_overlap=10)
+
+        assert len(chunks) > 0
+        assert all(isinstance(chunk, str) for chunk in chunks)
+        assert all(len(chunk.strip()) > 0 for chunk in chunks)
+
+    def test_create_traditional_chunks_empty_docs(self):
+        """Test traditional chunking with empty documents."""
+        chunks = create_traditional_chunks([], chunk_size=50, chunk_overlap=10)
+        assert chunks == []
+
+    @pytest.mark.skipif(
+        os.environ.get("CI") == "true",
+        reason="Skip astchunk tests in CI - dependency may not be available",
+    )
+    def test_create_ast_chunks_with_astchunk_available(self):
+        """Test AST chunking when astchunk is available."""
+        python_code = '''
+def hello_world():
+    """Print hello world message."""
+    print("Hello, World!")
+
+def add_numbers(a, b):
+    """Add two numbers and return the result."""
+    return a + b
+
+class Calculator:
+    """A simple calculator class."""
+
+    def __init__(self):
+        self.history = []
+
+    def add(self, a, b):
+        result = a + b
+        self.history.append(f"{a} + {b} = {result}")
+        return result
+'''
+
+        docs = [MockDocument(python_code, "/test/calculator.py", {"language": "python"})]
+
+        try:
+            chunks = create_ast_chunks(docs, max_chunk_size=200, chunk_overlap=50)
+
+            # Should have multiple chunks due to different functions/classes
+            assert len(chunks) > 0
+            assert all(isinstance(chunk, str) for chunk in chunks)
+            assert all(len(chunk.strip()) > 0 for chunk in chunks)
+
+            # Check that code structure is somewhat preserved
+            combined_content = " ".join(chunks)
+            assert "def hello_world" in combined_content
+            assert "class Calculator" in combined_content
+
+        except ImportError:
+            # astchunk not available, should fall back to traditional chunking
+            chunks = create_ast_chunks(docs, max_chunk_size=200, chunk_overlap=50)
+            assert len(chunks) > 0  # Should still get chunks from fallback
+
+    def test_create_ast_chunks_fallback_to_traditional(self):
+        """Test AST chunking falls back to traditional when astchunk is not available."""
+        docs = [MockDocument("def test(): pass", "/test/script.py", {"language": "python"})]
+
+        # Mock astchunk import to fail
+        with patch("chunking.create_ast_chunks"):
+            # First call (actual test) should import astchunk and potentially fail
+            # Let's call the actual function to test the import error handling
+            chunks = create_ast_chunks(docs)
+
+            # Should return some chunks (either from astchunk or fallback)
+            assert isinstance(chunks, list)
+
+    def test_create_text_chunks_traditional_mode(self):
+        """Test text chunking in traditional mode."""
+        docs = [
+            MockDocument("def test(): pass", "/test/script.py"),
+            MockDocument("This is regular text.", "/test/doc.txt"),
+        ]
+
+        chunks = create_text_chunks(docs, use_ast_chunking=False, chunk_size=50, chunk_overlap=10)
+
+        assert len(chunks) > 0
+        assert all(isinstance(chunk, str) for chunk in chunks)
+
+    def test_create_text_chunks_ast_mode(self):
+        """Test text chunking in AST mode."""
+        docs = [
+            MockDocument("def test(): pass", "/test/script.py"),
+            MockDocument("This is regular text.", "/test/doc.txt"),
+        ]
+
+        chunks = create_text_chunks(
+            docs,
+            use_ast_chunking=True,
+            ast_chunk_size=100,
+            ast_chunk_overlap=20,
+            chunk_size=50,
+            chunk_overlap=10,
+        )
+
+        assert len(chunks) > 0
+        assert all(isinstance(chunk, str) for chunk in chunks)
+
+    def test_create_text_chunks_custom_extensions(self):
+        """Test text chunking with custom code file extensions."""
+        docs = [
+            MockDocument("function test() {}", "/test/script.js"),  # Not in default extensions
+            MockDocument("Regular text", "/test/doc.txt"),
+        ]
+
+        # First without custom extensions - should treat .js as text
+        chunks_without = create_text_chunks(docs, use_ast_chunking=True, code_file_extensions=None)
+
+        # Then with custom extensions - should treat .js as code
+        chunks_with = create_text_chunks(
+            docs, use_ast_chunking=True, code_file_extensions=[".js", ".jsx"]
+        )
+
+        # Both should return chunks
+        assert len(chunks_without) > 0
+        assert len(chunks_with) > 0
+
+
+class TestIntegrationWithDocumentRAG:
+    """Integration tests with the document RAG system."""
+
+    @pytest.fixture
+    def temp_code_dir(self):
+        """Create a temporary directory with sample code files."""
+        with tempfile.TemporaryDirectory() as temp_dir:
+            temp_path = Path(temp_dir)
+
+            # Create sample Python file
+            python_file = temp_path / "example.py"
+            python_file.write_text('''
+def fibonacci(n):
+    """Calculate fibonacci number."""
+    if n <= 1:
+        return n
+    return fibonacci(n-1) + fibonacci(n-2)
+
+class MathUtils:
+    @staticmethod
+    def factorial(n):
+        if n <= 1:
+            return 1
+        return n * MathUtils.factorial(n-1)
+''')
+
+            # Create sample text file
+            text_file = temp_path / "readme.txt"
+            text_file.write_text("This is a sample text file for testing purposes.")
+
+            yield temp_path
+
+    @pytest.mark.skipif(
+        os.environ.get("CI") == "true",
+        reason="Skip integration tests in CI to avoid dependency issues",
+    )
+    def test_document_rag_with_ast_chunking(self, temp_code_dir):
+        """Test document RAG with AST chunking enabled."""
+        with tempfile.TemporaryDirectory() as index_dir:
+            cmd = [
+                sys.executable,
+                "apps/document_rag.py",
+                "--llm",
+                "simulated",
+                "--embedding-model",
+                "facebook/contriever",
+                "--embedding-mode",
+                "sentence-transformers",
+                "--index-dir",
+                index_dir,
+                "--data-dir",
+                str(temp_code_dir),
+                "--enable-code-chunking",
+                "--query",
+                "How does the fibonacci function work?",
+            ]
+
+            env = os.environ.copy()
+            env["HF_HUB_DISABLE_SYMLINKS"] = "1"
+            env["TOKENIZERS_PARALLELISM"] = "false"
+
+            try:
+                result = subprocess.run(
+                    cmd,
+                    capture_output=True,
+                    text=True,
+                    timeout=300,  # 5 minutes
+                    env=env,
+                )
+
+                # Should succeed even if astchunk is not available (fallback)
+                assert result.returncode == 0, f"Command failed: {result.stderr}"
+
+                output = result.stdout + result.stderr
+                assert "Index saved to" in output or "Using existing index" in output
+
+            except subprocess.TimeoutExpired:
+                pytest.skip("Test timed out - likely due to model download in CI")
+
+    @pytest.mark.skipif(
+        os.environ.get("CI") == "true",
+        reason="Skip integration tests in CI to avoid dependency issues",
+    )
+    def test_code_rag_application(self, temp_code_dir):
+        """Test the specialized code RAG application."""
+        with tempfile.TemporaryDirectory() as index_dir:
+            cmd = [
+                sys.executable,
+                "apps/code_rag.py",
+                "--llm",
+                "simulated",
+                "--embedding-model",
+                "facebook/contriever",
+                "--index-dir",
+                index_dir,
+                "--repo-dir",
+                str(temp_code_dir),
+                "--query",
+                "What classes are defined in this code?",
+            ]
+
+            env = os.environ.copy()
+            env["HF_HUB_DISABLE_SYMLINKS"] = "1"
+            env["TOKENIZERS_PARALLELISM"] = "false"
+
+            try:
+                result = subprocess.run(cmd, capture_output=True, text=True, timeout=300, env=env)
+
+                # Should succeed
+                assert result.returncode == 0, f"Command failed: {result.stderr}"
+
+                output = result.stdout + result.stderr
+                assert "Using AST-aware chunking" in output or "traditional chunking" in output
+
+            except subprocess.TimeoutExpired:
+                pytest.skip("Test timed out - likely due to model download in CI")
+
+
+class TestErrorHandling:
+    """Test error handling and edge cases."""
+
+    def test_text_chunking_empty_documents(self):
+        """Test text chunking with empty document list."""
+        chunks = create_text_chunks([])
+        assert chunks == []
+
+    def test_text_chunking_invalid_parameters(self):
+        """Test text chunking with invalid parameters."""
+        docs = [MockDocument("test content")]
+
+        # Should handle negative chunk sizes gracefully
+        chunks = create_text_chunks(
+            docs, chunk_size=0, chunk_overlap=0, ast_chunk_size=0, ast_chunk_overlap=0
+        )
+
+        # Should still return some result
+        assert isinstance(chunks, list)
+
+    def test_create_ast_chunks_no_language(self):
+        """Test AST chunking with documents missing language metadata."""
+        docs = [MockDocument("def test(): pass", "/test/script.py")]  # No language set
+
+        chunks = create_ast_chunks(docs)
+
+        # Should fall back to traditional chunking
+        assert isinstance(chunks, list)
+        assert len(chunks) >= 0  # May be empty if fallback also fails
+
+    def test_create_ast_chunks_empty_content(self):
+        """Test AST chunking with empty content."""
+        docs = [MockDocument("", "/test/script.py", {"language": "python"})]
+
+        chunks = create_ast_chunks(docs)
+
+        # Should handle empty content gracefully
+        assert isinstance(chunks, list)
+
+
+if __name__ == "__main__":
+    pytest.main([__file__, "-v"])

tests/test_basic.py

@@ -64,6 +64,9 @@ def test_backend_basic(backend_name):
         assert isinstance(results[0], SearchResult)
         assert "topic 2" in results[0].text or "document" in results[0].text
 
+        # Ensure cleanup to avoid hanging background servers
+        searcher.cleanup()
+
 
 @pytest.mark.skipif(
     os.environ.get("CI") == "true", reason="Skip model tests in CI to avoid MPS memory issues"
@@ -90,3 +93,5 @@ def test_large_index():
         searcher = LeannSearcher(index_path)
         results = searcher.search(["word10 word20"], top_k=10)
         assert len(results[0]) == 10
+        # Cleanup
+        searcher.cleanup()

tests/test_diskann_partition.py

@@ -0,0 +1,369 @@
+"""
+Test DiskANN graph partitioning functionality.
+
+Tests the automatic graph partitioning feature that was implemented to save
+storage space by partitioning large DiskANN indices and safely deleting
+redundant files while maintaining search functionality.
+"""
+
+import os
+import tempfile
+from pathlib import Path
+
+import pytest
+
+
+@pytest.mark.skipif(
+    os.environ.get("CI") == "true",
+    reason="Skip DiskANN partition tests in CI - requires specific hardware and large memory",
+)
+def test_diskann_without_partition():
+    """Test DiskANN index building without partition (baseline)."""
+    from leann.api import LeannBuilder, LeannSearcher
+
+    with tempfile.TemporaryDirectory() as temp_dir:
+        index_path = str(Path(temp_dir) / "test_no_partition.leann")
+
+        # Test data - enough to trigger index building
+        texts = [
+            f"Document {i} discusses topic {i % 10} with detailed analysis of subject {i // 10}."
+            for i in range(500)
+        ]
+
+        # Build without partition (is_recompute=False)
+        builder = LeannBuilder(
+            backend_name="diskann",
+            embedding_model="facebook/contriever",
+            embedding_mode="sentence-transformers",
+            num_neighbors=32,
+            search_list_size=50,
+            is_recompute=False,  # No partition
+        )
+
+        for text in texts:
+            builder.add_text(text)
+
+        builder.build_index(index_path)
+
+        # Verify index was created
+        index_dir = Path(index_path).parent
+        assert index_dir.exists()
+
+        # Check that traditional DiskANN files exist
+        index_prefix = Path(index_path).stem
+        # Core DiskANN files (beam search index may not be created for small datasets)
+        required_files = [
+            f"{index_prefix}_disk.index",
+            f"{index_prefix}_pq_compressed.bin",
+            f"{index_prefix}_pq_pivots.bin",
+        ]
+
+        # Check all generated files first for debugging
+        generated_files = [f.name for f in index_dir.glob(f"{index_prefix}*")]
+        print(f"Generated files: {generated_files}")
+
+        for required_file in required_files:
+            file_path = index_dir / required_file
+            assert file_path.exists(), f"Required file {required_file} not found"
+
+        # Ensure no partition files exist in non-partition mode
+        partition_files = [f"{index_prefix}_disk_graph.index", f"{index_prefix}_partition.bin"]
+
+        for partition_file in partition_files:
+            file_path = index_dir / partition_file
+            assert not file_path.exists(), (
+                f"Partition file {partition_file} should not exist in non-partition mode"
+            )
+
+        # Test search functionality
+        searcher = LeannSearcher(index_path)
+        results = searcher.search("topic 3 analysis", top_k=3)
+
+        assert len(results) > 0
+        assert all(result.score is not None and result.score != float("-inf") for result in results)
+
+
+@pytest.mark.skipif(
+    os.environ.get("CI") == "true",
+    reason="Skip DiskANN partition tests in CI - requires specific hardware and large memory",
+)
+def test_diskann_with_partition():
+    """Test DiskANN index building with automatic graph partitioning."""
+    from leann.api import LeannBuilder
+
+    with tempfile.TemporaryDirectory() as temp_dir:
+        index_path = str(Path(temp_dir) / "test_with_partition.leann")
+
+        # Test data - enough to trigger partitioning
+        texts = [
+            f"Document {i} explores subject {i % 15} with comprehensive coverage of area {i // 15}."
+            for i in range(500)
+        ]
+
+        # Build with partition (is_recompute=True)
+        builder = LeannBuilder(
+            backend_name="diskann",
+            embedding_model="facebook/contriever",
+            embedding_mode="sentence-transformers",
+            num_neighbors=32,
+            search_list_size=50,
+            is_recompute=True,  # Enable automatic partitioning
+        )
+
+        for text in texts:
+            builder.add_text(text)
+
+        builder.build_index(index_path)
+
+        # Verify index was created
+        index_dir = Path(index_path).parent
+        assert index_dir.exists()
+
+        # Check that partition files exist
+        index_prefix = Path(index_path).stem
+        partition_files = [
+            f"{index_prefix}_disk_graph.index",  # Partitioned graph
+            f"{index_prefix}_partition.bin",  # Partition metadata
+            f"{index_prefix}_pq_compressed.bin",
+            f"{index_prefix}_pq_pivots.bin",
+        ]
+
+        for partition_file in partition_files:
+            file_path = index_dir / partition_file
+            assert file_path.exists(), f"Expected partition file {partition_file} not found"
+
+        # Check that large files were cleaned up (storage saving goal)
+        large_files = [f"{index_prefix}_disk.index", f"{index_prefix}_disk_beam_search.index"]
+
+        for large_file in large_files:
+            file_path = index_dir / large_file
+            assert not file_path.exists(), (
+                f"Large file {large_file} should have been deleted for storage saving"
+            )
+
+        # Verify required auxiliary files for partition mode exist
+        required_files = [
+            f"{index_prefix}_disk.index_medoids.bin",
+            f"{index_prefix}_disk.index_max_base_norm.bin",
+        ]
+
+        for req_file in required_files:
+            file_path = index_dir / req_file
+            assert file_path.exists(), (
+                f"Required auxiliary file {req_file} missing for partition mode"
+            )
+
+
+@pytest.mark.skipif(
+    os.environ.get("CI") == "true",
+    reason="Skip DiskANN partition tests in CI - requires specific hardware and large memory",
+)
+def test_diskann_partition_search_functionality():
+    """Test that search works correctly with partitioned indices."""
+    from leann.api import LeannBuilder, LeannSearcher
+
+    with tempfile.TemporaryDirectory() as temp_dir:
+        index_path = str(Path(temp_dir) / "test_partition_search.leann")
+
+        # Create diverse test data
+        texts = [
+            "LEANN is a storage-efficient approximate nearest neighbor search system.",
+            "Graph partitioning helps reduce memory usage in large scale vector search.",
+            "DiskANN provides high-performance disk-based approximate nearest neighbor search.",
+            "Vector embeddings enable semantic search over unstructured text data.",
+            "Approximate nearest neighbor algorithms trade accuracy for speed and storage.",
+        ] * 100  # Repeat to get enough data
+
+        # Build with partitioning
+        builder = LeannBuilder(
+            backend_name="diskann",
+            embedding_model="facebook/contriever",
+            embedding_mode="sentence-transformers",
+            is_recompute=True,  # Enable partitioning
+        )
+
+        for text in texts:
+            builder.add_text(text)
+
+        builder.build_index(index_path)
+
+        # Test search with partitioned index
+        searcher = LeannSearcher(index_path)
+
+        # Test various queries
+        test_queries = [
+            ("vector search algorithms", 5),
+            ("LEANN storage efficiency", 3),
+            ("graph partitioning memory", 4),
+            ("approximate nearest neighbor", 7),
+        ]
+
+        for query, top_k in test_queries:
+            results = searcher.search(query, top_k=top_k)
+
+            # Verify search results
+            assert len(results) == top_k, f"Expected {top_k} results for query '{query}'"
+            assert all(result.score is not None for result in results), (
+                "All results should have scores"
+            )
+            assert all(result.score != float("-inf") for result in results), (
+                "No result should have -inf score"
+            )
+            assert all(result.text is not None for result in results), (
+                "All results should have text"
+            )
+
+            # Scores should be in descending order (higher similarity first)
+            scores = [result.score for result in results]
+            assert scores == sorted(scores, reverse=True), (
+                "Results should be sorted by score descending"
+            )
+
+
+@pytest.mark.skipif(
+    os.environ.get("CI") == "true",
+    reason="Skip DiskANN partition tests in CI - requires specific hardware and large memory",
+)
+def test_diskann_medoid_and_norm_files():
+    """Test that medoid and max_base_norm files are correctly generated and used."""
+    import struct
+
+    from leann.api import LeannBuilder, LeannSearcher
+
+    with tempfile.TemporaryDirectory() as temp_dir:
+        index_path = str(Path(temp_dir) / "test_medoid_norm.leann")
+
+        # Small but sufficient dataset
+        texts = [f"Test document {i} with content about subject {i % 10}." for i in range(200)]
+
+        builder = LeannBuilder(
+            backend_name="diskann",
+            embedding_model="facebook/contriever",
+            embedding_mode="sentence-transformers",
+            is_recompute=True,
+        )
+
+        for text in texts:
+            builder.add_text(text)
+
+        builder.build_index(index_path)
+
+        index_dir = Path(index_path).parent
+        index_prefix = Path(index_path).stem
+
+        # Test medoids file
+        medoids_file = index_dir / f"{index_prefix}_disk.index_medoids.bin"
+        assert medoids_file.exists(), "Medoids file should be generated"
+
+        # Read and validate medoids file format
+        with open(medoids_file, "rb") as f:
+            nshards = struct.unpack("<I", f.read(4))[0]
+            one_val = struct.unpack("<I", f.read(4))[0]
+            medoid_id = struct.unpack("<I", f.read(4))[0]
+
+            assert nshards == 1, "Single-shot build should have 1 shard"
+            assert one_val == 1, "Expected value should be 1"
+            assert medoid_id >= 0, "Medoid ID should be valid (not hardcoded 0)"
+
+        # Test max_base_norm file
+        norm_file = index_dir / f"{index_prefix}_disk.index_max_base_norm.bin"
+        assert norm_file.exists(), "Max base norm file should be generated"
+
+        # Read and validate norm file
+        with open(norm_file, "rb") as f:
+            npts = struct.unpack("<I", f.read(4))[0]
+            ndims = struct.unpack("<I", f.read(4))[0]
+            norm_val = struct.unpack("<f", f.read(4))[0]
+
+            assert npts == 1, "Should have 1 norm point"
+            assert ndims == 1, "Should have 1 dimension"
+            assert norm_val > 0, "Norm value should be positive"
+            assert norm_val != float("inf"), "Norm value should be finite"
+
+        # Test that search works with these files
+        searcher = LeannSearcher(index_path)
+        results = searcher.search("test subject", top_k=3)
+
+        # Verify that scores are not -inf (which indicates norm file was loaded correctly)
+        assert len(results) > 0
+        assert all(result.score != float("-inf") for result in results), (
+            "Scores should not be -inf when norm file is correct"
+        )
+
+
+@pytest.mark.skipif(
+    os.environ.get("CI") == "true",
+    reason="Skip performance comparison in CI - requires significant compute time",
+)
+def test_diskann_vs_hnsw_performance():
+    """Compare DiskANN (with partition) vs HNSW performance."""
+    import time
+
+    from leann.api import LeannBuilder, LeannSearcher
+
+    with tempfile.TemporaryDirectory() as temp_dir:
+        # Test data
+        texts = [
+            f"Performance test document {i} covering topic {i % 20} in detail." for i in range(1000)
+        ]
+        query = "performance topic test"
+
+        # Test DiskANN with partitioning
+        diskann_path = str(Path(temp_dir) / "perf_diskann.leann")
+        diskann_builder = LeannBuilder(
+            backend_name="diskann",
+            embedding_model="facebook/contriever",
+            embedding_mode="sentence-transformers",
+            is_recompute=True,
+        )
+
+        for text in texts:
+            diskann_builder.add_text(text)
+
+        start_time = time.time()
+        diskann_builder.build_index(diskann_path)
+
+        # Test HNSW
+        hnsw_path = str(Path(temp_dir) / "perf_hnsw.leann")
+        hnsw_builder = LeannBuilder(
+            backend_name="hnsw",
+            embedding_model="facebook/contriever",
+            embedding_mode="sentence-transformers",
+            is_recompute=True,
+        )
+
+        for text in texts:
+            hnsw_builder.add_text(text)
+
+        start_time = time.time()
+        hnsw_builder.build_index(hnsw_path)
+
+        # Compare search performance
+        diskann_searcher = LeannSearcher(diskann_path)
+        hnsw_searcher = LeannSearcher(hnsw_path)
+
+        # Warm up searches
+        diskann_searcher.search(query, top_k=5)
+        hnsw_searcher.search(query, top_k=5)
+
+        # Timed searches
+        start_time = time.time()
+        diskann_results = diskann_searcher.search(query, top_k=10)
+        diskann_search_time = time.time() - start_time
+
+        start_time = time.time()
+        hnsw_results = hnsw_searcher.search(query, top_k=10)
+        hnsw_search_time = time.time() - start_time
+
+        # Basic assertions
+        assert len(diskann_results) == 10
+        assert len(hnsw_results) == 10
+        assert all(r.score != float("-inf") for r in diskann_results)
+        assert all(r.score != float("-inf") for r in hnsw_results)
+
+        # Performance ratio (informational)
+        if hnsw_search_time > 0:
+            speed_ratio = hnsw_search_time / diskann_search_time
+            print(f"DiskANN search time: {diskann_search_time:.4f}s")
+            print(f"HNSW search time: {hnsw_search_time:.4f}s")
+            print(f"DiskANN is {speed_ratio:.2f}x faster than HNSW")

tests/test_document_rag.py

@@ -57,7 +57,55 @@ def test_document_rag_simulated(test_data_dir):
         assert "This is a simulated answer" in output
 
 
+@pytest.mark.skipif(
+    os.environ.get("CI") == "true",
+    reason="Skip AST chunking tests in CI to avoid dependency issues",
+)
+def test_document_rag_with_ast_chunking(test_data_dir):
+    """Test document_rag with AST-aware chunking enabled."""
+    with tempfile.TemporaryDirectory() as temp_dir:
+        # Use a subdirectory that doesn't exist yet to force index creation
+        index_dir = Path(temp_dir) / "test_ast_index"
+        cmd = [
+            sys.executable,
+            "apps/document_rag.py",
+            "--llm",
+            "simulated",
+            "--embedding-model",
+            "facebook/contriever",
+            "--embedding-mode",
+            "sentence-transformers",
+            "--index-dir",
+            str(index_dir),
+            "--data-dir",
+            str(test_data_dir),
+            "--enable-code-chunking",  # Enable AST chunking
+            "--query",
+            "What is Pride and Prejudice about?",
+        ]
+
+        env = os.environ.copy()
+        env["HF_HUB_DISABLE_SYMLINKS"] = "1"
+        env["TOKENIZERS_PARALLELISM"] = "false"
+
+        result = subprocess.run(cmd, capture_output=True, text=True, timeout=600, env=env)
+
+        # Check return code
+        assert result.returncode == 0, f"Command failed: {result.stderr}"
+
+        # Verify output
+        output = result.stdout + result.stderr
+        assert "Index saved to" in output or "Using existing index" in output
+        assert "This is a simulated answer" in output
+
+        # Should mention AST chunking if code files are present
+        # (might not be relevant for the test data, but command should succeed)
+
+
 @pytest.mark.skipif(not os.environ.get("OPENAI_API_KEY"), reason="OpenAI API key not available")
+@pytest.mark.skipif(
+    os.environ.get("CI") == "true", reason="Skip OpenAI tests in CI to avoid API costs"
+)
 def test_document_rag_openai(test_data_dir):
     """Test document_rag with OpenAI embeddings."""
     with tempfile.TemporaryDirectory() as temp_dir:

tests/test_mcp_integration.py

@@ -0,0 +1,209 @@
+#!/usr/bin/env python3
+"""
+Test script for MCP integration implementations.
+
+This script tests the basic functionality of the MCP readers and RAG applications
+without requiring actual MCP servers to be running.
+"""
+
+import sys
+import asyncio
+from pathlib import Path
+
+# Add the parent directory to the path so we can import from apps
+sys.path.append(str(Path(__file__).parent.parent))
+
+from apps.slack_data.slack_mcp_reader import SlackMCPReader
+from apps.twitter_data.twitter_mcp_reader import TwitterMCPReader
+from apps.slack_rag import SlackMCPRAG
+from apps.twitter_rag import TwitterMCPRAG
+
+
+def test_slack_reader_initialization():
+    """Test that SlackMCPReader can be initialized with various parameters."""
+    print("Testing SlackMCPReader initialization...")
+    
+    # Test basic initialization
+    reader = SlackMCPReader("slack-mcp-server")
+    assert reader.mcp_server_command == "slack-mcp-server"
+    assert reader.concatenate_conversations == True
+    assert reader.max_messages_per_conversation == 100
+    
+    # Test with custom parameters
+    reader = SlackMCPReader(
+        "custom-slack-server",
+        workspace_name="test-workspace",
+        concatenate_conversations=False,
+        max_messages_per_conversation=50
+    )
+    assert reader.workspace_name == "test-workspace"
+    assert reader.concatenate_conversations == False
+    assert reader.max_messages_per_conversation == 50
+    
+    print("✅ SlackMCPReader initialization tests passed")
+
+
+def test_twitter_reader_initialization():
+    """Test that TwitterMCPReader can be initialized with various parameters."""
+    print("Testing TwitterMCPReader initialization...")
+    
+    # Test basic initialization
+    reader = TwitterMCPReader("twitter-mcp-server")
+    assert reader.mcp_server_command == "twitter-mcp-server"
+    assert reader.include_tweet_content == True
+    assert reader.include_metadata == True
+    assert reader.max_bookmarks == 1000
+    
+    # Test with custom parameters
+    reader = TwitterMCPReader(
+        "custom-twitter-server",
+        username="testuser",
+        include_tweet_content=False,
+        include_metadata=False,
+        max_bookmarks=500
+    )
+    assert reader.username == "testuser"
+    assert reader.include_tweet_content == False
+    assert reader.include_metadata == False
+    assert reader.max_bookmarks == 500
+    
+    print("✅ TwitterMCPReader initialization tests passed")
+
+
+def test_slack_message_formatting():
+    """Test Slack message formatting functionality."""
+    print("Testing Slack message formatting...")
+    
+    reader = SlackMCPReader("slack-mcp-server")
+    
+    # Test basic message formatting
+    message = {
+        "text": "Hello, world!",
+        "user": "john_doe",
+        "channel": "general",
+        "ts": "1234567890.123456"
+    }
+    
+    formatted = reader._format_message(message)
+    assert "Channel: #general" in formatted
+    assert "User: john_doe" in formatted
+    assert "Message: Hello, world!" in formatted
+    assert "Time:" in formatted
+    
+    # Test with missing fields
+    message = {"text": "Simple message"}
+    formatted = reader._format_message(message)
+    assert "Message: Simple message" in formatted
+    
+    print("✅ Slack message formatting tests passed")
+
+
+def test_twitter_bookmark_formatting():
+    """Test Twitter bookmark formatting functionality."""
+    print("Testing Twitter bookmark formatting...")
+    
+    reader = TwitterMCPReader("twitter-mcp-server")
+    
+    # Test basic bookmark formatting
+    bookmark = {
+        "text": "This is a great article about AI!",
+        "author": "ai_researcher",
+        "created_at": "2024-01-01T12:00:00Z",
+        "url": "https://twitter.com/ai_researcher/status/123456789",
+        "likes": 42,
+        "retweets": 15
+    }
+    
+    formatted = reader._format_bookmark(bookmark)
+    assert "=== Twitter Bookmark ===" in formatted
+    assert "Author: @ai_researcher" in formatted
+    assert "Content:" in formatted
+    assert "This is a great article about AI!" in formatted
+    assert "URL: https://twitter.com" in formatted
+    assert "Likes: 42" in formatted
+    assert "Retweets: 15" in formatted
+    
+    # Test with minimal data
+    bookmark = {"text": "Simple tweet"}
+    formatted = reader._format_bookmark(bookmark)
+    assert "=== Twitter Bookmark ===" in formatted
+    assert "Simple tweet" in formatted
+    
+    print("✅ Twitter bookmark formatting tests passed")
+
+
+def test_slack_rag_initialization():
+    """Test that SlackMCPRAG can be initialized."""
+    print("Testing SlackMCPRAG initialization...")
+    
+    app = SlackMCPRAG()
+    assert app.default_index_name == "slack_messages"
+    assert hasattr(app, 'parser')
+    
+    print("✅ SlackMCPRAG initialization tests passed")
+
+
+def test_twitter_rag_initialization():
+    """Test that TwitterMCPRAG can be initialized."""
+    print("Testing TwitterMCPRAG initialization...")
+    
+    app = TwitterMCPRAG()
+    assert app.default_index_name == "twitter_bookmarks"
+    assert hasattr(app, 'parser')
+    
+    print("✅ TwitterMCPRAG initialization tests passed")
+
+
+def test_concatenated_content_creation():
+    """Test creation of concatenated content from multiple messages."""
+    print("Testing concatenated content creation...")
+    
+    reader = SlackMCPReader("slack-mcp-server", workspace_name="test-workspace")
+    
+    messages = [
+        {"text": "First message", "user": "alice", "ts": "1000"},
+        {"text": "Second message", "user": "bob", "ts": "2000"},
+        {"text": "Third message", "user": "charlie", "ts": "3000"}
+    ]
+    
+    content = reader._create_concatenated_content(messages, "general")
+    
+    assert "Slack Channel: #general" in content
+    assert "Message Count: 3" in content
+    assert "Workspace: test-workspace" in content
+    assert "First message" in content
+    assert "Second message" in content
+    assert "Third message" in content
+    
+    print("✅ Concatenated content creation tests passed")
+
+
+def main():
+    """Run all tests."""
+    print("🧪 Running MCP Integration Tests")
+    print("=" * 50)
+    
+    try:
+        test_slack_reader_initialization()
+        test_twitter_reader_initialization()
+        test_slack_message_formatting()
+        test_twitter_bookmark_formatting()
+        test_slack_rag_initialization()
+        test_twitter_rag_initialization()
+        test_concatenated_content_creation()
+        
+        print("\n" + "=" * 50)
+        print("🎉 All tests passed! MCP integration is working correctly.")
+        print("\nNext steps:")
+        print("1. Install actual MCP servers for Slack and Twitter")
+        print("2. Configure API credentials")
+        print("3. Test with --test-connection flag")
+        print("4. Start indexing your live data!")
+        
+    except Exception as e:
+        print(f"\n❌ Test failed: {e}")
+        sys.exit(1)
+
+
+if __name__ == "__main__":
+    main()

tests/test_mcp_standalone.py

@@ -0,0 +1,225 @@
+#!/usr/bin/env python3
+"""
+Standalone test script for MCP integration implementations.
+
+This script tests the basic functionality of the MCP readers
+without requiring LEANN core dependencies.
+"""
+
+import sys
+import json
+from pathlib import Path
+
+# Add the parent directory to the path so we can import from apps
+sys.path.append(str(Path(__file__).parent.parent))
+
+
+def test_slack_reader_basic():
+    """Test basic SlackMCPReader functionality without async operations."""
+    print("Testing SlackMCPReader basic functionality...")
+    
+    # Import and test initialization
+    from apps.slack_data.slack_mcp_reader import SlackMCPReader
+    
+    reader = SlackMCPReader("slack-mcp-server")
+    assert reader.mcp_server_command == "slack-mcp-server"
+    assert reader.concatenate_conversations == True
+    
+    # Test message formatting
+    message = {
+        "text": "Hello team! How's the project going?",
+        "user": "john_doe",
+        "channel": "general",
+        "ts": "1234567890.123456"
+    }
+    
+    formatted = reader._format_message(message)
+    assert "Channel: #general" in formatted
+    assert "User: john_doe" in formatted
+    assert "Message: Hello team!" in formatted
+    
+    # Test concatenated content creation
+    messages = [
+        {"text": "First message", "user": "alice", "ts": "1000"},
+        {"text": "Second message", "user": "bob", "ts": "2000"}
+    ]
+    
+    content = reader._create_concatenated_content(messages, "dev-team")
+    assert "Slack Channel: #dev-team" in content
+    assert "Message Count: 2" in content
+    assert "First message" in content
+    assert "Second message" in content
+    
+    print("✅ SlackMCPReader basic tests passed")
+
+
+def test_twitter_reader_basic():
+    """Test basic TwitterMCPReader functionality."""
+    print("Testing TwitterMCPReader basic functionality...")
+    
+    from apps.twitter_data.twitter_mcp_reader import TwitterMCPReader
+    
+    reader = TwitterMCPReader("twitter-mcp-server")
+    assert reader.mcp_server_command == "twitter-mcp-server"
+    assert reader.include_tweet_content == True
+    assert reader.max_bookmarks == 1000
+    
+    # Test bookmark formatting
+    bookmark = {
+        "text": "Amazing article about the future of AI! Must read for everyone interested in tech.",
+        "author": "tech_guru",
+        "created_at": "2024-01-15T14:30:00Z",
+        "url": "https://twitter.com/tech_guru/status/123456789",
+        "likes": 156,
+        "retweets": 42,
+        "replies": 23,
+        "hashtags": ["AI", "tech", "future"],
+        "mentions": ["@openai", "@anthropic"]
+    }
+    
+    formatted = reader._format_bookmark(bookmark)
+    assert "=== Twitter Bookmark ===" in formatted
+    assert "Author: @tech_guru" in formatted
+    assert "Amazing article about the future of AI!" in formatted
+    assert "Likes: 156" in formatted
+    assert "Retweets: 42" in formatted
+    assert "Hashtags: AI, tech, future" in formatted
+    assert "Mentions: @openai, @anthropic" in formatted
+    
+    # Test with minimal data
+    simple_bookmark = {"text": "Short tweet", "author": "user123"}
+    formatted_simple = reader._format_bookmark(simple_bookmark)
+    assert "=== Twitter Bookmark ===" in formatted_simple
+    assert "Short tweet" in formatted_simple
+    assert "Author: @user123" in formatted_simple
+    
+    print("✅ TwitterMCPReader basic tests passed")
+
+
+def test_mcp_request_format():
+    """Test MCP request formatting."""
+    print("Testing MCP request formatting...")
+    
+    # Test initialization request format
+    init_request = {
+        "jsonrpc": "2.0",
+        "id": 1,
+        "method": "initialize",
+        "params": {
+            "protocolVersion": "2024-11-05",
+            "capabilities": {},
+            "clientInfo": {"name": "leann-slack-reader", "version": "1.0.0"}
+        }
+    }
+    
+    # Verify it's valid JSON
+    json_str = json.dumps(init_request)
+    parsed = json.loads(json_str)
+    assert parsed["jsonrpc"] == "2.0"
+    assert parsed["method"] == "initialize"
+    assert parsed["params"]["protocolVersion"] == "2024-11-05"
+    
+    # Test tools/list request
+    list_request = {
+        "jsonrpc": "2.0",
+        "id": 2,
+        "method": "tools/list",
+        "params": {}
+    }
+    
+    json_str = json.dumps(list_request)
+    parsed = json.loads(json_str)
+    assert parsed["method"] == "tools/list"
+    
+    print("✅ MCP request formatting tests passed")
+
+
+def test_data_processing():
+    """Test data processing capabilities."""
+    print("Testing data processing capabilities...")
+    
+    from apps.slack_data.slack_mcp_reader import SlackMCPReader
+    from apps.twitter_data.twitter_mcp_reader import TwitterMCPReader
+    
+    # Test Slack message processing with various formats
+    slack_reader = SlackMCPReader("test-server")
+    
+    messages_with_timestamps = [
+        {"text": "Meeting in 5 minutes", "user": "alice", "ts": "1000.123"},
+        {"text": "On my way!", "user": "bob", "ts": "1001.456"},
+        {"text": "Starting now", "user": "charlie", "ts": "1002.789"}
+    ]
+    
+    content = slack_reader._create_concatenated_content(messages_with_timestamps, "meetings")
+    assert "Meeting in 5 minutes" in content
+    assert "On my way!" in content
+    assert "Starting now" in content
+    
+    # Test Twitter bookmark processing with engagement data
+    twitter_reader = TwitterMCPReader("test-server", include_metadata=True)
+    
+    high_engagement_bookmark = {
+        "text": "Thread about startup lessons learned 🧵",
+        "author": "startup_founder",
+        "likes": 1250,
+        "retweets": 340,
+        "replies": 89
+    }
+    
+    formatted = twitter_reader._format_bookmark(high_engagement_bookmark)
+    assert "Thread about startup lessons learned" in formatted
+    assert "Likes: 1250" in formatted
+    assert "Retweets: 340" in formatted
+    assert "Replies: 89" in formatted
+    
+    # Test with metadata disabled
+    twitter_reader_no_meta = TwitterMCPReader("test-server", include_metadata=False)
+    formatted_no_meta = twitter_reader_no_meta._format_bookmark(high_engagement_bookmark)
+    assert "Thread about startup lessons learned" in formatted_no_meta
+    assert "Likes:" not in formatted_no_meta
+    assert "Retweets:" not in formatted_no_meta
+    
+    print("✅ Data processing tests passed")
+
+
+def main():
+    """Run all standalone tests."""
+    print("🧪 Running MCP Integration Standalone Tests")
+    print("=" * 60)
+    print("Testing core functionality without LEANN dependencies...")
+    print()
+    
+    try:
+        test_slack_reader_basic()
+        test_twitter_reader_basic()
+        test_mcp_request_format()
+        test_data_processing()
+        
+        print("\n" + "=" * 60)
+        print("🎉 All standalone tests passed!")
+        print("\n✨ MCP Integration Summary:")
+        print("- SlackMCPReader: Ready for Slack message processing")
+        print("- TwitterMCPReader: Ready for Twitter bookmark processing") 
+        print("- MCP Protocol: Properly formatted JSON-RPC requests")
+        print("- Data Processing: Handles various message/bookmark formats")
+        
+        print("\n🚀 Next Steps:")
+        print("1. Install MCP servers: npm install -g slack-mcp-server twitter-mcp-server")
+        print("2. Configure API credentials for Slack and Twitter")
+        print("3. Test connections: python -m apps.slack_rag --test-connection")
+        print("4. Start indexing live data from your platforms!")
+        
+        print("\n📖 Documentation:")
+        print("- Check README.md for detailed setup instructions")
+        print("- Run examples/mcp_integration_demo.py for usage examples")
+        print("- Explore apps/slack_rag.py and apps/twitter_rag.py for implementation details")
+        
+    except Exception as e:
+        print(f"\n❌ Test failed: {e}")
+        import traceback
+        traceback.print_exc()
+        sys.exit(1)
+
+
+if __name__ == "__main__":
+    main()

tests/test_metadata_filtering.py

@@ -0,0 +1,365 @@
+"""
+Comprehensive tests for metadata filtering functionality.
+
+This module tests the MetadataFilterEngine class and its integration
+with the LEANN search system.
+"""
+
+import os
+
+# Import the modules we're testing
+import sys
+from unittest.mock import Mock, patch
+
+sys.path.insert(0, os.path.join(os.path.dirname(__file__), "../packages/leann-core/src"))
+
+from leann.api import PassageManager, SearchResult
+from leann.metadata_filter import MetadataFilterEngine
+
+
+class TestMetadataFilterEngine:
+    """Test suite for the MetadataFilterEngine class."""
+
+    def setup_method(self):
+        """Setup test fixtures."""
+        self.engine = MetadataFilterEngine()
+
+        # Sample search results for testing
+        self.sample_results = [
+            {
+                "id": "doc1",
+                "score": 0.95,
+                "text": "This is chapter 1 content",
+                "metadata": {
+                    "chapter": 1,
+                    "character": "Alice",
+                    "tags": ["adventure", "fantasy"],
+                    "word_count": 150,
+                    "is_published": True,
+                    "genre": "fiction",
+                },
+            },
+            {
+                "id": "doc2",
+                "score": 0.87,
+                "text": "This is chapter 3 content",
+                "metadata": {
+                    "chapter": 3,
+                    "character": "Bob",
+                    "tags": ["mystery", "thriller"],
+                    "word_count": 250,
+                    "is_published": True,
+                    "genre": "fiction",
+                },
+            },
+            {
+                "id": "doc3",
+                "score": 0.82,
+                "text": "This is chapter 5 content",
+                "metadata": {
+                    "chapter": 5,
+                    "character": "Alice",
+                    "tags": ["romance", "drama"],
+                    "word_count": 300,
+                    "is_published": False,
+                    "genre": "non-fiction",
+                },
+            },
+            {
+                "id": "doc4",
+                "score": 0.78,
+                "text": "This is chapter 10 content",
+                "metadata": {
+                    "chapter": 10,
+                    "character": "Charlie",
+                    "tags": ["action", "adventure"],
+                    "word_count": 400,
+                    "is_published": True,
+                    "genre": "fiction",
+                },
+            },
+        ]
+
+    def test_engine_initialization(self):
+        """Test that the filter engine initializes correctly."""
+        assert self.engine is not None
+        assert len(self.engine.operators) > 0
+        assert "==" in self.engine.operators
+        assert "contains" in self.engine.operators
+        assert "in" in self.engine.operators
+
+    def test_direct_instantiation(self):
+        """Test direct instantiation of the engine."""
+        engine = MetadataFilterEngine()
+        assert isinstance(engine, MetadataFilterEngine)
+
+    def test_no_filters_returns_all_results(self):
+        """Test that passing None or empty filters returns all results."""
+        # Test with None
+        result = self.engine.apply_filters(self.sample_results, None)
+        assert len(result) == len(self.sample_results)
+
+        # Test with empty dict
+        result = self.engine.apply_filters(self.sample_results, {})
+        assert len(result) == len(self.sample_results)
+
+    # Test comparison operators
+    def test_equals_filter(self):
+        """Test equals (==) filter."""
+        filters = {"chapter": {"==": 1}}
+        result = self.engine.apply_filters(self.sample_results, filters)
+        assert len(result) == 1
+        assert result[0]["id"] == "doc1"
+
+    def test_not_equals_filter(self):
+        """Test not equals (!=) filter."""
+        filters = {"genre": {"!=": "fiction"}}
+        result = self.engine.apply_filters(self.sample_results, filters)
+        assert len(result) == 1
+        assert result[0]["metadata"]["genre"] == "non-fiction"
+
+    def test_less_than_filter(self):
+        """Test less than (<) filter."""
+        filters = {"chapter": {"<": 5}}
+        result = self.engine.apply_filters(self.sample_results, filters)
+        assert len(result) == 2
+        chapters = [r["metadata"]["chapter"] for r in result]
+        assert all(ch < 5 for ch in chapters)
+
+    def test_less_than_or_equal_filter(self):
+        """Test less than or equal (<=) filter."""
+        filters = {"chapter": {"<=": 5}}
+        result = self.engine.apply_filters(self.sample_results, filters)
+        assert len(result) == 3
+        chapters = [r["metadata"]["chapter"] for r in result]
+        assert all(ch <= 5 for ch in chapters)
+
+    def test_greater_than_filter(self):
+        """Test greater than (>) filter."""
+        filters = {"word_count": {">": 200}}
+        result = self.engine.apply_filters(self.sample_results, filters)
+        assert len(result) == 3  # Documents with word_count 250, 300, 400
+        word_counts = [r["metadata"]["word_count"] for r in result]
+        assert all(wc > 200 for wc in word_counts)
+
+    def test_greater_than_or_equal_filter(self):
+        """Test greater than or equal (>=) filter."""
+        filters = {"word_count": {">=": 250}}
+        result = self.engine.apply_filters(self.sample_results, filters)
+        assert len(result) == 3
+        word_counts = [r["metadata"]["word_count"] for r in result]
+        assert all(wc >= 250 for wc in word_counts)
+
+    # Test membership operators
+    def test_in_filter(self):
+        """Test in filter."""
+        filters = {"character": {"in": ["Alice", "Bob"]}}
+        result = self.engine.apply_filters(self.sample_results, filters)
+        assert len(result) == 3
+        characters = [r["metadata"]["character"] for r in result]
+        assert all(ch in ["Alice", "Bob"] for ch in characters)
+
+    def test_not_in_filter(self):
+        """Test not_in filter."""
+        filters = {"character": {"not_in": ["Alice", "Bob"]}}
+        result = self.engine.apply_filters(self.sample_results, filters)
+        assert len(result) == 1
+        assert result[0]["metadata"]["character"] == "Charlie"
+
+    # Test string operators
+    def test_contains_filter(self):
+        """Test contains filter."""
+        filters = {"genre": {"contains": "fiction"}}
+        result = self.engine.apply_filters(self.sample_results, filters)
+        assert len(result) == 4  # Both "fiction" and "non-fiction"
+
+    def test_starts_with_filter(self):
+        """Test starts_with filter."""
+        filters = {"genre": {"starts_with": "non"}}
+        result = self.engine.apply_filters(self.sample_results, filters)
+        assert len(result) == 1
+        assert result[0]["metadata"]["genre"] == "non-fiction"
+
+    def test_ends_with_filter(self):
+        """Test ends_with filter."""
+        filters = {"text": {"ends_with": "content"}}
+        result = self.engine.apply_filters(self.sample_results, filters)
+        assert len(result) == 4  # All sample texts end with "content"
+
+    # Test boolean operators
+    def test_is_true_filter(self):
+        """Test is_true filter."""
+        filters = {"is_published": {"is_true": True}}
+        result = self.engine.apply_filters(self.sample_results, filters)
+        assert len(result) == 3
+        assert all(r["metadata"]["is_published"] for r in result)
+
+    def test_is_false_filter(self):
+        """Test is_false filter."""
+        filters = {"is_published": {"is_false": False}}
+        result = self.engine.apply_filters(self.sample_results, filters)
+        assert len(result) == 1
+        assert not result[0]["metadata"]["is_published"]
+
+    # Test compound filters (AND logic)
+    def test_compound_filters(self):
+        """Test multiple filters applied together (AND logic)."""
+        filters = {"genre": {"==": "fiction"}, "chapter": {"<=": 5}}
+        result = self.engine.apply_filters(self.sample_results, filters)
+        assert len(result) == 2
+        for r in result:
+            assert r["metadata"]["genre"] == "fiction"
+            assert r["metadata"]["chapter"] <= 5
+
+    def test_multiple_operators_same_field(self):
+        """Test multiple operators on the same field."""
+        filters = {"word_count": {">=": 200, "<=": 350}}
+        result = self.engine.apply_filters(self.sample_results, filters)
+        assert len(result) == 2
+        for r in result:
+            wc = r["metadata"]["word_count"]
+            assert 200 <= wc <= 350
+
+    # Test edge cases
+    def test_missing_field_fails_filter(self):
+        """Test that missing metadata fields fail filters."""
+        filters = {"nonexistent_field": {"==": "value"}}
+        result = self.engine.apply_filters(self.sample_results, filters)
+        assert len(result) == 0
+
+    def test_invalid_operator(self):
+        """Test that invalid operators are handled gracefully."""
+        filters = {"chapter": {"invalid_op": 1}}
+        result = self.engine.apply_filters(self.sample_results, filters)
+        assert len(result) == 0  # Should filter out all results
+
+    def test_type_coercion_numeric(self):
+        """Test numeric type coercion in comparisons."""
+        # Add a result with string chapter number
+        test_results = [
+            *self.sample_results,
+            {
+                "id": "doc5",
+                "score": 0.75,
+                "text": "String chapter test",
+                "metadata": {"chapter": "2", "genre": "test"},
+            },
+        ]
+
+        filters = {"chapter": {"<": 3}}
+        result = self.engine.apply_filters(test_results, filters)
+        # Should include doc1 (chapter=1) and doc5 (chapter="2")
+        assert len(result) == 2
+        ids = [r["id"] for r in result]
+        assert "doc1" in ids
+        assert "doc5" in ids
+
+    def test_list_membership_with_nested_tags(self):
+        """Test membership operations with list metadata."""
+        # Note: This tests the metadata structure, not list field filtering
+        # For list field filtering, we'd need to modify the test data
+        filters = {"character": {"in": ["Alice"]}}
+        result = self.engine.apply_filters(self.sample_results, filters)
+        assert len(result) == 2
+        assert all(r["metadata"]["character"] == "Alice" for r in result)
+
+    def test_empty_results_list(self):
+        """Test filtering on empty results list."""
+        filters = {"chapter": {"==": 1}}
+        result = self.engine.apply_filters([], filters)
+        assert len(result) == 0
+
+
+class TestPassageManagerFiltering:
+    """Test suite for PassageManager filtering integration."""
+
+    def setup_method(self):
+        """Setup test fixtures."""
+        # Mock the passage manager without actual file I/O
+        self.passage_manager = Mock(spec=PassageManager)
+        self.passage_manager.filter_engine = MetadataFilterEngine()
+
+        # Sample SearchResult objects
+        self.search_results = [
+            SearchResult(
+                id="doc1",
+                score=0.95,
+                text="Chapter 1 content",
+                metadata={"chapter": 1, "character": "Alice"},
+            ),
+            SearchResult(
+                id="doc2",
+                score=0.87,
+                text="Chapter 5 content",
+                metadata={"chapter": 5, "character": "Bob"},
+            ),
+            SearchResult(
+                id="doc3",
+                score=0.82,
+                text="Chapter 10 content",
+                metadata={"chapter": 10, "character": "Alice"},
+            ),
+        ]
+
+    def test_search_result_filtering(self):
+        """Test filtering SearchResult objects."""
+        # Create a real PassageManager instance just for the filtering method
+        # We'll mock the file operations
+        with patch("builtins.open"), patch("json.loads"), patch("pickle.load"):
+            pm = PassageManager([{"type": "jsonl", "path": "test.jsonl"}])
+
+            filters = {"chapter": {"<=": 5}}
+            result = pm.filter_search_results(self.search_results, filters)
+
+            assert len(result) == 2
+            chapters = [r.metadata["chapter"] for r in result]
+            assert all(ch <= 5 for ch in chapters)
+
+    def test_filter_search_results_no_filters(self):
+        """Test that None filters return all results."""
+        with patch("builtins.open"), patch("json.loads"), patch("pickle.load"):
+            pm = PassageManager([{"type": "jsonl", "path": "test.jsonl"}])
+
+            result = pm.filter_search_results(self.search_results, None)
+            assert len(result) == len(self.search_results)
+
+    def test_filter_maintains_search_result_type(self):
+        """Test that filtering returns SearchResult objects."""
+        with patch("builtins.open"), patch("json.loads"), patch("pickle.load"):
+            pm = PassageManager([{"type": "jsonl", "path": "test.jsonl"}])
+
+            filters = {"character": {"==": "Alice"}}
+            result = pm.filter_search_results(self.search_results, filters)
+
+            assert len(result) == 2
+            for r in result:
+                assert isinstance(r, SearchResult)
+                assert r.metadata["character"] == "Alice"
+
+
+# Integration tests would go here, but they require actual LEANN backend setup
+# These would test the full pipeline from LeannSearcher.search() with metadata_filters
+
+if __name__ == "__main__":
+    # Run basic smoke tests
+    engine = MetadataFilterEngine()
+
+    sample_data = [
+        {
+            "id": "test1",
+            "score": 0.9,
+            "text": "Test content",
+            "metadata": {"chapter": 1, "published": True},
+        }
+    ]
+
+    # Test basic filtering
+    result = engine.apply_filters(sample_data, {"chapter": {"==": 1}})
+    assert len(result) == 1
+    print("✅ Basic filtering test passed")
+
+    result = engine.apply_filters(sample_data, {"chapter": {"==": 2}})
+    assert len(result) == 0
+    print("✅ No match filtering test passed")
+
+    print("🎉 All smoke tests passed!")

tests/test_readme_examples.py

@@ -10,29 +10,33 @@ from pathlib import Path
 import pytest
 
 
-def test_readme_basic_example():
-    """Test the basic example from README.md."""
+@pytest.mark.parametrize("backend_name", ["hnsw", "diskann"])
+def test_readme_basic_example(backend_name):
+    """Test the basic example from README.md with both backends."""
     # Skip on macOS CI due to MPS environment issues with all-MiniLM-L6-v2
     if os.environ.get("CI") == "true" and platform.system() == "Darwin":
         pytest.skip("Skipping on macOS CI due to MPS environment issues with all-MiniLM-L6-v2")
+    # Skip DiskANN on CI (Linux runners) due to C++ extension memory/hardware constraints
+    if os.environ.get("CI") == "true" and backend_name == "diskann":
+        pytest.skip("Skip DiskANN tests in CI due to resource constraints and instability")
 
     # This is the exact code from README (with smaller model for CI)
     from leann import LeannBuilder, LeannChat, LeannSearcher
     from leann.api import SearchResult
 
     with tempfile.TemporaryDirectory() as temp_dir:
-        INDEX_PATH = str(Path(temp_dir) / "demo.leann")
+        INDEX_PATH = str(Path(temp_dir) / f"demo_{backend_name}.leann")
 
         # Build an index
         # In CI, use a smaller model to avoid memory issues
         if os.environ.get("CI") == "true":
             builder = LeannBuilder(
-                backend_name="hnsw",
+                backend_name=backend_name,
                 embedding_model="sentence-transformers/all-MiniLM-L6-v2",  # Smaller model
                 dimensions=384,  # Smaller dimensions
             )
         else:
-            builder = LeannBuilder(backend_name="hnsw")
+            builder = LeannBuilder(backend_name=backend_name)
         builder.add_text("LEANN saves 97% storage compared to traditional vector databases.")
         builder.add_text("Tung Tung Tung Sahur called—they need their banana-crocodile hybrid back")
         builder.build_index(INDEX_PATH)
@@ -52,9 +56,15 @@ def test_readme_basic_example():
         # Verify search results
         assert len(results) > 0
         assert isinstance(results[0], SearchResult)
+        assert results[0].score != float("-inf"), (
+            f"should return valid scores, got {results[0].score}"
+        )
         # The second text about banana-crocodile should be more relevant
         assert "banana" in results[0].text or "crocodile" in results[0].text
 
+        # Ensure we cleanup background embedding server
+        searcher.cleanup()
+
         # Chat with your data (using simulated LLM to avoid external dependencies)
         chat = LeannChat(INDEX_PATH, llm_config={"type": "simulated"})
         response = chat.ask("How much storage does LEANN save?", top_k=1)
@@ -62,6 +72,8 @@ def test_readme_basic_example():
         # Verify chat works
         assert isinstance(response, str)
         assert len(response) > 0
+        # Cleanup chat resources
+        chat.cleanup()
 
 
 def test_readme_imports():
@@ -110,26 +122,31 @@ def test_backend_options():
         assert len(list(Path(diskann_path).parent.glob(f"{Path(diskann_path).stem}.*"))) > 0
 
 
-def test_llm_config_simulated():
-    """Test simulated LLM configuration option."""
+@pytest.mark.parametrize("backend_name", ["hnsw", "diskann"])
+def test_llm_config_simulated(backend_name):
+    """Test simulated LLM configuration option with both backends."""
     # Skip on macOS CI due to MPS environment issues with all-MiniLM-L6-v2
     if os.environ.get("CI") == "true" and platform.system() == "Darwin":
         pytest.skip("Skipping on macOS CI due to MPS environment issues with all-MiniLM-L6-v2")
 
+    # Skip DiskANN tests in CI due to hardware requirements
+    if os.environ.get("CI") == "true" and backend_name == "diskann":
+        pytest.skip("Skip DiskANN tests in CI - requires specific hardware and large memory")
+
     from leann import LeannBuilder, LeannChat
 
     with tempfile.TemporaryDirectory() as temp_dir:
         # Build a simple index
-        index_path = str(Path(temp_dir) / "test.leann")
+        index_path = str(Path(temp_dir) / f"test_{backend_name}.leann")
         # Use smaller model in CI to avoid memory issues
         if os.environ.get("CI") == "true":
             builder = LeannBuilder(
-                backend_name="hnsw",
+                backend_name=backend_name,
                 embedding_model="sentence-transformers/all-MiniLM-L6-v2",
                 dimensions=384,
             )
         else:
-            builder = LeannBuilder(backend_name="hnsw")
+            builder = LeannBuilder(backend_name=backend_name)
         builder.add_text("Test document for LLM testing")
         builder.build_index(index_path)