Add ColQwen2.5 model support and improve model selection

- Add ColQwen2.5 and ColQwen2_5_Processor imports
- Implement smart model type detection for colqwen2, colqwen2.5, and colpali
- Add task name aliases for easier benchmark invocation
- Add safe model name handling for file paths and index naming
- Support custom model paths including LoRA adapters
- Improve model choice validation and error handling

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

.github/workflows/link-check.yml

@@ -14,6 +14,6 @@ jobs:
       - uses: actions/checkout@v4
       - uses: lycheeverse/lychee-action@v2
         with:
-          args: --no-progress --insecure --user-agent 'curl/7.68.0' README.md docs/ apps/ examples/ benchmarks/
+          args: --no-progress --insecure --user-agent 'curl/7.68.0' --exclude '.*api\.star-history\.com.*' --accept 200,201,202,203,204,205,206,207,208,226,300,301,302,303,304,305,306,307,308,503 README.md docs/ apps/ examples/ benchmarks/
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

.gitignore

@@ -91,7 +91,8 @@ packages/leann-backend-diskann/third_party/DiskANN/_deps/
 
 *.meta.json
 *.passages.json
-
+*.npy
+*.db
 batchtest.py
 tests/__pytest_cache__/
 tests/__pycache__/

README.md

@@ -16,12 +16,24 @@
   </a>
 </p>
 
+<div align="center">
+  <a href="https://forms.gle/rDbZf864gMNxhpTq8">
+    <img src="https://img.shields.io/badge/📣_Community_Survey-Help_Shape_v0.4-007ec6?style=for-the-badge&logo=google-forms&logoColor=white" alt="Take Survey">
+  </a>
+  <p>
+    We track <b>zero telemetry</b>. This survey is the ONLY way to tell us if you want <br>
+    <b>GPU Acceleration</b> or <b>More Integrations</b> next.<br>
+    👉 <a href="https://forms.gle/rDbZf864gMNxhpTq8"><b>Click here to cast your vote (2 mins)</b></a>
+  </p>
+</div>
+
 <h2 align="center" tabindex="-1" class="heading-element" dir="auto">
     The smallest vector index in the world. RAG Everything with LEANN!
 </h2>
 
 LEANN is an innovative vector database that democratizes personal AI. Transform your laptop into a powerful RAG system that can index and search through millions of documents while using **97% less storage** than traditional solutions **without accuracy loss**.
 
+
 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)** ([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)), **[live data](#mcp-integration-rag-on-live-data-from-any-platform)** ([Slack](#mcp-integration-rag-on-live-data-from-any-platform), [Twitter](#mcp-integration-rag-on-live-data-from-any-platform)), **[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.

apps/multimodal/vision-based-pdf-multi-vector/colqwen_forward.py

@@ -0,0 +1,132 @@
+#!/usr/bin/env python3
+"""Simple test script to test colqwen2 forward pass with a single image."""
+
+import os
+import sys
+from pathlib import Path
+
+# Add the current directory to path to import leann_multi_vector
+sys.path.insert(0, str(Path(__file__).parent))
+
+import torch
+from leann_multi_vector import _embed_images, _ensure_repo_paths_importable, _load_colvision
+from PIL import Image
+
+# Ensure repo paths are importable
+_ensure_repo_paths_importable(__file__)
+
+# Set environment variable
+os.environ["TOKENIZERS_PARALLELISM"] = "false"
+
+
+def create_test_image():
+    """Create a simple test image."""
+    # Create a simple RGB image (800x600)
+    img = Image.new("RGB", (800, 600), color="white")
+    return img
+
+
+def load_test_image_from_file():
+    """Try to load an image from the indexes directory if available."""
+    # Try to find an existing image in the indexes directory
+    indexes_dir = Path(__file__).parent / "indexes"
+
+    # Look for images in common locations
+    possible_paths = [
+        indexes_dir / "vidore_fastplaid" / "images",
+        indexes_dir / "colvision_large.leann.images",
+        indexes_dir / "colvision.leann.images",
+    ]
+
+    for img_dir in possible_paths:
+        if img_dir.exists():
+            # Find first image file
+            for ext in [".png", ".jpg", ".jpeg"]:
+                for img_file in img_dir.glob(f"*{ext}"):
+                    print(f"Loading test image from: {img_file}")
+                    return Image.open(img_file)
+
+    return None
+
+
+def main():
+    print("=" * 60)
+    print("Testing ColQwen2 Forward Pass")
+    print("=" * 60)
+
+    # Step 1: Load or create test image
+    print("\n[Step 1] Loading test image...")
+    test_image = load_test_image_from_file()
+    if test_image is None:
+        print("No existing image found, creating a simple test image...")
+        test_image = create_test_image()
+    else:
+        print(f"✓ Loaded image: {test_image.size} ({test_image.mode})")
+
+    # Convert to RGB if needed
+    if test_image.mode != "RGB":
+        test_image = test_image.convert("RGB")
+        print(f"✓ Converted to RGB: {test_image.size}")
+
+    # Step 2: Load model
+    print("\n[Step 2] Loading ColQwen2 model...")
+    try:
+        model_name, model, processor, device_str, device, dtype = _load_colvision("colqwen2")
+        print(f"✓ Model loaded: {model_name}")
+        print(f"✓ Device: {device_str}, dtype: {dtype}")
+
+        # Print model info
+        if hasattr(model, "device"):
+            print(f"✓ Model device: {model.device}")
+        if hasattr(model, "dtype"):
+            print(f"✓ Model dtype: {model.dtype}")
+
+    except Exception as e:
+        print(f"✗ Error loading model: {e}")
+        import traceback
+
+        traceback.print_exc()
+        return
+
+    # Step 3: Test forward pass
+    print("\n[Step 3] Running forward pass...")
+    try:
+        # Use the _embed_images function which handles batching and forward pass
+        images = [test_image]
+        print(f"Processing {len(images)} image(s)...")
+
+        doc_vecs = _embed_images(model, processor, images)
+
+        print("✓ Forward pass completed!")
+        print(f"✓ Number of embeddings: {len(doc_vecs)}")
+
+        if len(doc_vecs) > 0:
+            emb = doc_vecs[0]
+            print(f"✓ Embedding shape: {emb.shape}")
+            print(f"✓ Embedding dtype: {emb.dtype}")
+            print("✓ Embedding stats:")
+            print(f"    - Min: {emb.min().item():.4f}")
+            print(f"    - Max: {emb.max().item():.4f}")
+            print(f"    - Mean: {emb.mean().item():.4f}")
+            print(f"    - Std: {emb.std().item():.4f}")
+
+            # Check for NaN or Inf
+            if torch.isnan(emb).any():
+                print("⚠ Warning: Embedding contains NaN values!")
+            if torch.isinf(emb).any():
+                print("⚠ Warning: Embedding contains Inf values!")
+
+    except Exception as e:
+        print(f"✗ Error during forward pass: {e}")
+        import traceback
+
+        traceback.print_exc()
+        return
+
+    print("\n" + "=" * 60)
+    print("Test completed successfully!")
+    print("=" * 60)
+
+
+if __name__ == "__main__":
+    main()

apps/multimodal/vision-based-pdf-multi-vector/leann_multi_vector.py

@@ -3,6 +3,7 @@ import json
 import os
 import re
 import sys
+import time
 from pathlib import Path
 from typing import Any, Optional, cast
 
@@ -151,20 +152,65 @@ def _select_device_and_dtype():
 
 def _load_colvision(model_choice: str):
     import torch
-    from colpali_engine.models import ColPali, ColQwen2, ColQwen2Processor
+    from colpali_engine.models import (
+        ColPali,
+        ColQwen2,
+        ColQwen2_5,
+        ColQwen2_5_Processor,
+        ColQwen2Processor,
+    )
     from colpali_engine.models.paligemma.colpali.processing_colpali import ColPaliProcessor
     from transformers.utils.import_utils import is_flash_attn_2_available
 
     device_str, device, dtype = _select_device_and_dtype()
 
+    # Determine model name and type
+    # IMPORTANT: Check colqwen2.5 BEFORE colqwen2 to avoid false matches
+    model_choice_lower = model_choice.lower()
     if model_choice == "colqwen2":
         model_name = "vidore/colqwen2-v1.0"
-        # On CPU/MPS we must avoid flash-attn and stay eager; on CUDA prefer flash-attn if available
-        attn_implementation = (
-            "flash_attention_2"
-            if (device_str == "cuda" and is_flash_attn_2_available())
-            else "eager"
-        )
+        model_type = "colqwen2"
+    elif model_choice == "colqwen2.5" or model_choice == "colqwen25":
+        model_name = "vidore/colqwen2.5-v0.2"
+        model_type = "colqwen2.5"
+    elif model_choice == "colpali":
+        model_name = "vidore/colpali-v1.2"
+        model_type = "colpali"
+    elif (
+        "colqwen2.5" in model_choice_lower
+        or "colqwen25" in model_choice_lower
+        or "colqwen2_5" in model_choice_lower
+    ):
+        # Handle HuggingFace model names like "vidore/colqwen2.5-v0.2"
+        model_name = model_choice
+        model_type = "colqwen2.5"
+    elif "colqwen2" in model_choice_lower and "colqwen2-v1.0" in model_choice_lower:
+        # Handle HuggingFace model names like "vidore/colqwen2-v1.0" (but not colqwen2.5)
+        model_name = model_choice
+        model_type = "colqwen2"
+    elif "colpali" in model_choice_lower:
+        # Handle HuggingFace model names like "vidore/colpali-v1.2"
+        model_name = model_choice
+        model_type = "colpali"
+    else:
+        # Default to colpali for backward compatibility
+        model_name = "vidore/colpali-v1.2"
+        model_type = "colpali"
+
+    # Load model based on type
+    attn_implementation = (
+        "flash_attention_2" if (device_str == "cuda" and is_flash_attn_2_available()) else "eager"
+    )
+
+    if model_type == "colqwen2.5":
+        model = ColQwen2_5.from_pretrained(
+            model_name,
+            torch_dtype=torch.bfloat16,
+            device_map=device,
+            attn_implementation=attn_implementation,
+        ).eval()
+        processor = ColQwen2_5_Processor.from_pretrained(model_name)
+    elif model_type == "colqwen2":
         model = ColQwen2.from_pretrained(
             model_name,
             torch_dtype=torch.bfloat16,
@@ -172,8 +218,7 @@ def _load_colvision(model_choice: str):
             attn_implementation=attn_implementation,
         ).eval()
         processor = ColQwen2Processor.from_pretrained(model_name)
-    else:
-        model_name = "vidore/colpali-v1.2"
+    else:  # colpali
         model = ColPali.from_pretrained(
             model_name,
             torch_dtype=torch.bfloat16,
@@ -194,7 +239,7 @@ def _embed_images(model, processor, images: list[Image.Image]) -> list[Any]:
 
     dataloader = DataLoader(
         dataset=ListDataset[Image.Image](images),
-        batch_size=1,
+        batch_size=32,
         shuffle=False,
         collate_fn=lambda x: processor.process_images(x),
     )
@@ -218,32 +263,47 @@ def _embed_images(model, processor, images: list[Image.Image]) -> list[Any]:
 
 def _embed_queries(model, processor, queries: list[str]) -> list[Any]:
     import torch
-    from colpali_engine.utils.torch_utils import ListDataset
-    from torch.utils.data import DataLoader
 
     model.eval()
 
-    dataloader = DataLoader(
-        dataset=ListDataset[str](queries),
-        batch_size=1,
-        shuffle=False,
-        collate_fn=lambda x: processor.process_queries(x),
-    )
+    # Match MTEB's exact query processing from ColPaliEngineWrapper.get_text_embeddings:
+    # 1. MTEB receives batch["text"] which already includes instruction/prompt (from _combine_queries_with_instruction_text)
+    # 2. Manually adds: query_prefix + text + query_augmentation_token * 10
+    # 3. Calls processor.process_queries(batch) where batch is now a list of strings
+    # 4. process_queries adds: query_prefix + text + suffix (suffix = query_augmentation_token * 10)
+    #
+    # This results in duplicate addition: query_prefix is added twice, query_augmentation_token * 20 total
+    # We need to match this exactly to reproduce MTEB results
+
+    all_embeds = []
+    batch_size = 32  # Match MTEB's default batch_size
+
+    with torch.no_grad():
+        for i in tqdm(range(0, len(queries), batch_size), desc="Embedding queries"):
+            batch_queries = queries[i : i + batch_size]
+
+            # Match MTEB: manually add query_prefix + text + query_augmentation_token * 10
+            # Then process_queries will add them again (resulting in 20 augmentation tokens total)
+            batch = [
+                processor.query_prefix + t + processor.query_augmentation_token * 10
+                for t in batch_queries
+            ]
+            inputs = processor.process_queries(batch)
+            inputs = {k: v.to(model.device) for k, v in inputs.items()}
 
-    q_vecs: list[Any] = []
-    for batch_query in tqdm(dataloader, desc="Embedding queries"):
-        with torch.no_grad():
-            batch_query = {k: v.to(model.device) for k, v in batch_query.items()}
             if model.device.type == "cuda":
                 with torch.autocast(
                     device_type="cuda",
                     dtype=model.dtype if model.dtype.is_floating_point else torch.bfloat16,
                 ):
-                    embeddings_query = model(**batch_query)
+                    outs = model(**inputs)
             else:
-                embeddings_query = model(**batch_query)
-        q_vecs.extend(list(torch.unbind(embeddings_query.to("cpu"))))
-    return q_vecs
+                outs = model(**inputs)
+
+            # Match MTEB: convert to float32 on CPU
+            all_embeds.extend(list(torch.unbind(outs.cpu().to(torch.float32))))
+
+    return all_embeds
 
 
 def _build_index(
@@ -283,6 +343,279 @@ def _load_retriever_if_index_exists(index_path: str) -> Optional[Any]:
     return None
 
 
+def _build_fast_plaid_index(
+    index_path: str,
+    doc_vecs: list[Any],
+    filepaths: list[str],
+    images: list[Image.Image],
+) -> tuple[Any, float]:
+    """
+    Build a Fast-Plaid index from document embeddings.
+
+    Args:
+        index_path: Path to save the Fast-Plaid index
+        doc_vecs: List of document embeddings (each is a tensor with shape [num_tokens, embedding_dim])
+        filepaths: List of filepath identifiers for each document
+        images: List of PIL Images corresponding to each document
+
+    Returns:
+        Tuple of (FastPlaid index object, build_time_in_seconds)
+    """
+    import torch
+    from fast_plaid import search as fast_plaid_search
+
+    print(f"    Preparing {len(doc_vecs)} document embeddings for Fast-Plaid...")
+    _t0 = time.perf_counter()
+
+    # Convert doc_vecs to list of tensors
+    documents_embeddings = []
+    for i, vec in enumerate(doc_vecs):
+        if i % 1000 == 0:
+            print(f"      Converting embedding {i}/{len(doc_vecs)}...")
+        if not isinstance(vec, torch.Tensor):
+            vec = (
+                torch.tensor(vec)
+                if isinstance(vec, np.ndarray)
+                else torch.from_numpy(np.array(vec))
+            )
+        # Ensure float32 for Fast-Plaid
+        if vec.dtype != torch.float32:
+            vec = vec.float()
+        documents_embeddings.append(vec)
+
+    print(f"    Converted {len(documents_embeddings)} embeddings")
+    if len(documents_embeddings) > 0:
+        print(f"    First embedding shape: {documents_embeddings[0].shape}")
+        print(f"    First embedding dtype: {documents_embeddings[0].dtype}")
+
+    # Prepare metadata for Fast-Plaid
+    print(f"    Preparing metadata for {len(filepaths)} documents...")
+    metadata_list = []
+    for i, filepath in enumerate(filepaths):
+        metadata_list.append(
+            {
+                "filepath": filepath,
+                "index": i,
+            }
+        )
+
+    # Create Fast-Plaid index
+    print(f"    Creating FastPlaid object with index path: {index_path}")
+    try:
+        fast_plaid_index = fast_plaid_search.FastPlaid(index=index_path)
+        print("    FastPlaid object created successfully")
+    except Exception as e:
+        print(f"    Error creating FastPlaid object: {type(e).__name__}: {e}")
+        import traceback
+
+        traceback.print_exc()
+        raise
+
+    print(f"    Calling fast_plaid_index.create() with {len(documents_embeddings)} documents...")
+    try:
+        fast_plaid_index.create(
+            documents_embeddings=documents_embeddings,
+            metadata=metadata_list,
+        )
+        print("    Fast-Plaid index created successfully")
+    except Exception as e:
+        print(f"    Error creating Fast-Plaid index: {type(e).__name__}: {e}")
+        import traceback
+
+        traceback.print_exc()
+        raise
+
+    build_secs = time.perf_counter() - _t0
+
+    # Save images separately (Fast-Plaid doesn't store images)
+    print(f"    Saving {len(images)} images...")
+    images_dir = Path(index_path) / "images"
+    images_dir.mkdir(parents=True, exist_ok=True)
+    for i, img in enumerate(tqdm(images, desc="Saving images")):
+        img_path = images_dir / f"doc_{i}.png"
+        img.save(str(img_path))
+
+    return fast_plaid_index, build_secs
+
+
+def _fast_plaid_index_exists(index_path: str) -> bool:
+    """
+    Check if Fast-Plaid index exists by checking for key files.
+    This avoids creating the FastPlaid object which may trigger memory allocation.
+
+    Args:
+        index_path: Path to the Fast-Plaid index
+
+    Returns:
+        True if index appears to exist, False otherwise
+    """
+    index_path_obj = Path(index_path)
+    if not index_path_obj.exists() or not index_path_obj.is_dir():
+        return False
+
+    # Fast-Plaid creates a SQLite database file for metadata
+    # Check for metadata.db as the most reliable indicator
+    metadata_db = index_path_obj / "metadata.db"
+    if metadata_db.exists() and metadata_db.stat().st_size > 0:
+        return True
+
+    # Also check if directory has any files (might be incomplete index)
+    try:
+        if any(index_path_obj.iterdir()):
+            return True
+    except Exception:
+        pass
+
+    return False
+
+
+def _load_fast_plaid_index_if_exists(index_path: str) -> Optional[Any]:
+    """
+    Load Fast-Plaid index if it exists.
+    First checks if index files exist, then creates the FastPlaid object.
+    The actual index data loading happens lazily when search is called.
+
+    Args:
+        index_path: Path to the Fast-Plaid index
+
+    Returns:
+        FastPlaid index object if exists, None otherwise
+    """
+    try:
+        from fast_plaid import search as fast_plaid_search
+
+        # First check if index files exist without creating the object
+        if not _fast_plaid_index_exists(index_path):
+            return None
+
+        # Now try to create FastPlaid object
+        # This may trigger some memory allocation, but the full index loading is deferred
+        fast_plaid_index = fast_plaid_search.FastPlaid(index=index_path)
+        return fast_plaid_index
+    except ImportError:
+        # fast-plaid not installed
+        return None
+    except Exception as e:
+        # Any error (including memory errors from Rust backend) - return None
+        # The error will be caught and index will be rebuilt
+        print(f"Warning: Could not load Fast-Plaid index: {type(e).__name__}: {e}")
+        return None
+
+
+def _search_fast_plaid(
+    fast_plaid_index: Any,
+    query_vec: Any,
+    top_k: int,
+) -> tuple[list[tuple[float, int]], float]:
+    """
+    Search Fast-Plaid index with a query embedding.
+
+    Args:
+        fast_plaid_index: FastPlaid index object
+        query_vec: Query embedding tensor with shape [num_tokens, embedding_dim]
+        top_k: Number of top results to return
+
+    Returns:
+        Tuple of (results_list, search_time_in_seconds)
+        results_list: List of (score, doc_id) tuples
+    """
+    import torch
+
+    _t0 = time.perf_counter()
+
+    # Ensure query is a torch tensor
+    if not isinstance(query_vec, torch.Tensor):
+        q_vec_tensor = (
+            torch.tensor(query_vec)
+            if isinstance(query_vec, np.ndarray)
+            else torch.from_numpy(np.array(query_vec))
+        )
+    else:
+        q_vec_tensor = query_vec
+
+    # Fast-Plaid expects shape [num_queries, num_tokens, embedding_dim]
+    if q_vec_tensor.dim() == 2:
+        q_vec_tensor = q_vec_tensor.unsqueeze(0)  # [1, num_tokens, embedding_dim]
+
+    # Perform search
+    scores = fast_plaid_index.search(
+        queries_embeddings=q_vec_tensor,
+        top_k=top_k,
+        show_progress=True,
+    )
+
+    search_secs = time.perf_counter() - _t0
+
+    # Convert Fast-Plaid results to same format as LEANN: list of (score, doc_id) tuples
+    results = []
+    if scores and len(scores) > 0:
+        query_results = scores[0]
+        # Fast-Plaid returns (doc_id, score), convert to (score, doc_id) to match LEANN format
+        results = [(float(score), int(doc_id)) for doc_id, score in query_results]
+
+    return results, search_secs
+
+
+def _get_fast_plaid_image(index_path: str, doc_id: int) -> Optional[Image.Image]:
+    """
+    Retrieve image for a document from Fast-Plaid index.
+
+    Args:
+        index_path: Path to the Fast-Plaid index
+        doc_id: Document ID returned by Fast-Plaid search
+
+    Returns:
+        PIL Image if found, None otherwise
+
+    Note: Uses metadata['index'] to get the actual file index, as Fast-Plaid
+    doc_id may differ from the file naming index.
+    """
+    # First get metadata to find the actual index used for file naming
+    metadata = _get_fast_plaid_metadata(index_path, doc_id)
+    if metadata is None:
+        # Fallback: try using doc_id directly
+        file_index = doc_id
+    else:
+        # Use the 'index' field from metadata, which matches the file naming
+        file_index = metadata.get("index", doc_id)
+
+    images_dir = Path(index_path) / "images"
+    image_path = images_dir / f"doc_{file_index}.png"
+
+    if image_path.exists():
+        return Image.open(image_path)
+
+    # If not found with index, try doc_id as fallback
+    if file_index != doc_id:
+        fallback_path = images_dir / f"doc_{doc_id}.png"
+        if fallback_path.exists():
+            return Image.open(fallback_path)
+
+    return None
+
+
+def _get_fast_plaid_metadata(index_path: str, doc_id: int) -> Optional[dict]:
+    """
+    Retrieve metadata for a document from Fast-Plaid index.
+
+    Args:
+        index_path: Path to the Fast-Plaid index
+        doc_id: Document ID
+
+    Returns:
+        Dictionary with metadata if found, None otherwise
+    """
+    try:
+        from fast_plaid import filtering
+
+        metadata_list = filtering.get(index=index_path, subset=[doc_id])
+        if metadata_list and len(metadata_list) > 0:
+            return metadata_list[0]
+    except Exception:
+        pass
+    return None
+
+
 def _generate_similarity_map(
     model,
     processor,
@@ -678,11 +1011,15 @@ class LeannMultiVector:
             return (float(score), doc_id)
 
         scores: list[tuple[float, int]] = []
+        # load and core time
+        start_time = time.time()
         with concurrent.futures.ThreadPoolExecutor(max_workers=max_workers) as ex:
             futures = [ex.submit(_score_one, doc_id) for doc_id in candidate_doc_ids]
             for fut in concurrent.futures.as_completed(futures):
                 scores.append(fut.result())
-
+        end_time = time.time()
+        print(f"Number of candidate doc ids: {len(candidate_doc_ids)}")
+        print(f"Time taken in load and core time: {end_time - start_time} seconds")
         scores.sort(key=lambda x: x[0], reverse=True)
         return scores[:topk] if len(scores) >= topk else scores
 
@@ -710,7 +1047,6 @@ class LeannMultiVector:
         emb_path = self._embeddings_path()
         if not emb_path.exists():
             return self.search(data, topk)
-
         all_embeddings = np.load(emb_path, mmap_mode="r")
         if all_embeddings.dtype != np.float32:
             all_embeddings = all_embeddings.astype(np.float32)
@@ -718,23 +1054,29 @@ class LeannMultiVector:
         assert self._docid_to_indices is not None
         candidate_doc_ids = list(self._docid_to_indices.keys())
 
-        def _score_one(doc_id: int) -> tuple[float, int]:
+        def _score_one(doc_id: int, _all_embeddings=all_embeddings) -> tuple[float, int]:
             token_indices = self._docid_to_indices.get(doc_id, [])
             if not token_indices:
                 return (0.0, doc_id)
-            doc_vecs = np.asarray(all_embeddings[token_indices], dtype=np.float32)
+            doc_vecs = np.asarray(_all_embeddings[token_indices], dtype=np.float32)
             sim = np.dot(data, doc_vecs.T)
             sim = np.nan_to_num(sim, nan=-1e30, posinf=1e30, neginf=-1e30)
             score = sim.max(axis=2).sum(axis=1) if sim.ndim == 3 else sim.max(axis=1).sum()
             return (float(score), doc_id)
 
         scores: list[tuple[float, int]] = []
+        # load and core time
+        start_time = time.time()
         with concurrent.futures.ThreadPoolExecutor(max_workers=max_workers) as ex:
             futures = [ex.submit(_score_one, d) for d in candidate_doc_ids]
             for fut in concurrent.futures.as_completed(futures):
                 scores.append(fut.result())
-
+        end_time = time.time()
+        # print number of candidate doc ids
+        print(f"Number of candidate doc ids: {len(candidate_doc_ids)}")
+        print(f"Time taken in load and core time: {end_time - start_time} seconds")
         scores.sort(key=lambda x: x[0], reverse=True)
+        del all_embeddings
         return scores[:topk] if len(scores) >= topk else scores
 
     def get_image(self, doc_id: int) -> Optional[Image.Image]:
@@ -778,3 +1120,259 @@ class LeannMultiVector:
                     "image_path": meta.get("image_path", ""),
                 }
         return None
+
+
+class ViDoReBenchmarkEvaluator:
+    """
+    A reusable class for evaluating ViDoRe benchmarks (v1 and v2).
+    This class encapsulates common functionality for building indexes, searching, and evaluating.
+    """
+
+    def __init__(
+        self,
+        model_name: str,
+        use_fast_plaid: bool = False,
+        top_k: int = 100,
+        first_stage_k: int = 500,
+        k_values: Optional[list[int]] = None,
+    ):
+        """
+        Initialize the evaluator.
+
+        Args:
+            model_name: Model name ("colqwen2" or "colpali")
+            use_fast_plaid: Whether to use Fast-Plaid instead of LEANN
+            top_k: Top-k results to retrieve
+            first_stage_k: First stage k for LEANN search
+            k_values: List of k values for evaluation metrics
+        """
+        self.model_name = model_name
+        self.use_fast_plaid = use_fast_plaid
+        self.top_k = top_k
+        self.first_stage_k = first_stage_k
+        self.k_values = k_values if k_values is not None else [1, 3, 5, 10, 100]
+
+        # Load model once (can be reused across tasks)
+        self._model = None
+        self._processor = None
+        self._model_name_actual = None
+
+    def _load_model_if_needed(self):
+        """Lazy load the model."""
+        if self._model is None:
+            print(f"\nLoading model: {self.model_name}")
+            self._model_name_actual, self._model, self._processor, _, _, _ = _load_colvision(
+                self.model_name
+            )
+            print(f"Model loaded: {self._model_name_actual}")
+
+    def build_index_from_corpus(
+        self,
+        corpus: dict[str, Image.Image],
+        index_path: str,
+        rebuild: bool = False,
+    ) -> tuple[Any, list[str]]:
+        """
+        Build index from corpus images.
+
+        Args:
+            corpus: dict mapping corpus_id to PIL Image
+            index_path: Path to save/load the index
+            rebuild: Whether to rebuild even if index exists
+
+        Returns:
+            tuple: (retriever or fast_plaid_index object, list of corpus_ids in order)
+        """
+        self._load_model_if_needed()
+
+        # Ensure consistent ordering
+        corpus_ids = sorted(corpus.keys())
+        images = [corpus[cid] for cid in corpus_ids]
+
+        if self.use_fast_plaid:
+            # Check if Fast-Plaid index exists
+            if not rebuild and _load_fast_plaid_index_if_exists(index_path) is not None:
+                print(f"Fast-Plaid index already exists at {index_path}")
+                return _load_fast_plaid_index_if_exists(index_path), corpus_ids
+
+            print(f"Building Fast-Plaid index at {index_path}...")
+            print("Embedding images...")
+            doc_vecs = _embed_images(self._model, self._processor, images)
+
+            fast_plaid_index, build_time = _build_fast_plaid_index(
+                index_path, doc_vecs, corpus_ids, images
+            )
+            print(f"Fast-Plaid index built in {build_time:.2f}s")
+            return fast_plaid_index, corpus_ids
+        else:
+            # Check if LEANN index exists
+            if not rebuild:
+                retriever = _load_retriever_if_index_exists(index_path)
+                if retriever is not None:
+                    print(f"LEANN index already exists at {index_path}")
+                    return retriever, corpus_ids
+
+            print(f"Building LEANN index at {index_path}...")
+            print("Embedding images...")
+            doc_vecs = _embed_images(self._model, self._processor, images)
+
+            retriever = _build_index(index_path, doc_vecs, corpus_ids, images)
+            print("LEANN index built")
+            return retriever, corpus_ids
+
+    def search_queries(
+        self,
+        queries: dict[str, str],
+        corpus_ids: list[str],
+        index_or_retriever: Any,
+        fast_plaid_index_path: Optional[str] = None,
+        task_prompt: Optional[dict[str, str]] = None,
+    ) -> dict[str, dict[str, float]]:
+        """
+        Search queries against the index.
+
+        Args:
+            queries: dict mapping query_id to query text
+            corpus_ids: list of corpus_ids in the same order as the index
+            index_or_retriever: index or retriever object
+            fast_plaid_index_path: path to Fast-Plaid index (for metadata)
+            task_prompt: Optional dict with prompt for query (e.g., {"query": "..."})
+
+        Returns:
+            results: dict mapping query_id to dict of {corpus_id: score}
+        """
+        self._load_model_if_needed()
+
+        print(f"Searching {len(queries)} queries (top_k={self.top_k})...")
+
+        query_ids = list(queries.keys())
+        query_texts = [queries[qid] for qid in query_ids]
+
+        # Note: ColPaliEngineWrapper does NOT use task prompt from metadata
+        # It uses query_prefix + text + query_augmentation_token (handled in _embed_queries)
+        # So we don't append task_prompt here to match MTEB behavior
+
+        # Embed queries
+        print("Embedding queries...")
+        query_vecs = _embed_queries(self._model, self._processor, query_texts)
+
+        results = {}
+
+        for query_id, query_vec in zip(tqdm(query_ids, desc="Searching"), query_vecs):
+            if self.use_fast_plaid:
+                # Fast-Plaid search
+                search_results, _ = _search_fast_plaid(index_or_retriever, query_vec, self.top_k)
+                query_results = {}
+                for score, doc_id in search_results:
+                    if doc_id < len(corpus_ids):
+                        corpus_id = corpus_ids[doc_id]
+                        query_results[corpus_id] = float(score)
+            else:
+                # LEANN search
+                import torch
+
+                query_np = (
+                    query_vec.float().numpy() if isinstance(query_vec, torch.Tensor) else query_vec
+                )
+                search_results = index_or_retriever.search_exact(query_np, topk=self.top_k)
+                query_results = {}
+                for score, doc_id in search_results:
+                    if doc_id < len(corpus_ids):
+                        corpus_id = corpus_ids[doc_id]
+                        query_results[corpus_id] = float(score)
+
+            results[query_id] = query_results
+
+        return results
+
+    @staticmethod
+    def evaluate_results(
+        results: dict[str, dict[str, float]],
+        qrels: dict[str, dict[str, int]],
+        k_values: Optional[list[int]] = None,
+    ) -> dict[str, float]:
+        """
+        Evaluate retrieval results using NDCG and other metrics.
+
+        Args:
+            results: dict mapping query_id to dict of {corpus_id: score}
+            qrels: dict mapping query_id to dict of {corpus_id: relevance_score}
+            k_values: List of k values for evaluation metrics
+
+        Returns:
+            Dictionary of metric scores
+        """
+        try:
+            from mteb._evaluators.retrieval_metrics import (
+                calculate_retrieval_scores,
+                make_score_dict,
+            )
+        except ImportError:
+            raise ImportError(
+                "pytrec_eval is required for evaluation. Install with: pip install pytrec-eval"
+            )
+
+        if k_values is None:
+            k_values = [1, 3, 5, 10, 100]
+
+        # Check if we have any queries to evaluate
+        if len(results) == 0:
+            print("Warning: No queries to evaluate. Returning zero scores.")
+            scores = {}
+            for k in k_values:
+                scores[f"ndcg_at_{k}"] = 0.0
+                scores[f"map_at_{k}"] = 0.0
+                scores[f"recall_at_{k}"] = 0.0
+                scores[f"precision_at_{k}"] = 0.0
+                scores[f"mrr_at_{k}"] = 0.0
+            return scores
+
+        print(f"Evaluating results with k_values={k_values}...")
+        print(f"Before filtering: {len(results)} results, {len(qrels)} qrels")
+
+        # Filter to ensure qrels and results have the same query set
+        # This matches MTEB behavior: only evaluate queries that exist in both
+        # pytrec_eval only evaluates queries in qrels, so we need to ensure
+        # results contains all queries in qrels, and filter out queries not in qrels
+        results_filtered = {qid: res for qid, res in results.items() if qid in qrels}
+        qrels_filtered = {
+            qid: rel_docs for qid, rel_docs in qrels.items() if qid in results_filtered
+        }
+
+        print(f"After filtering: {len(results_filtered)} results, {len(qrels_filtered)} qrels")
+
+        if len(results_filtered) != len(qrels_filtered):
+            print(
+                f"Warning: Mismatch between results ({len(results_filtered)}) and qrels ({len(qrels_filtered)}) queries"
+            )
+            missing_in_results = set(qrels.keys()) - set(results.keys())
+            if missing_in_results:
+                print(f"Queries in qrels but not in results: {len(missing_in_results)} queries")
+                print(f"First 5 missing queries: {list(missing_in_results)[:5]}")
+
+        # Convert qrels to pytrec_eval format
+        qrels_pytrec = {}
+        for qid, rel_docs in qrels_filtered.items():
+            qrels_pytrec[qid] = dict(rel_docs.items())
+
+        # Evaluate
+        eval_result = calculate_retrieval_scores(
+            results=results_filtered,
+            qrels=qrels_pytrec,
+            k_values=k_values,
+        )
+
+        # Format scores
+        scores = make_score_dict(
+            ndcg=eval_result.ndcg,
+            _map=eval_result.map,
+            recall=eval_result.recall,
+            precision=eval_result.precision,
+            mrr=eval_result.mrr,
+            naucs=eval_result.naucs,
+            naucs_mrr=eval_result.naucs_mrr,
+            cv_recall=eval_result.cv_recall,
+            task_scores={},
+        )
+
+        return scores

apps/multimodal/vision-based-pdf-multi-vector/multi-vector-leann-similarity-map.py

@@ -1,12 +1,19 @@
 ## Jupyter-style notebook script
 # %%
 # uv pip install matplotlib qwen_vl_utils
+import argparse
+import faulthandler
 import os
+import time
 from typing import Any, Optional
 
+import numpy as np
 from PIL import Image
 from tqdm import tqdm
 
+# Enable faulthandler to get stack trace on segfault
+faulthandler.enable()
+
 
 from leann_multi_vector import (  # utility functions/classes
     _ensure_repo_paths_importable,
@@ -18,6 +25,11 @@ from leann_multi_vector import (  # utility functions/classes
     _build_index,
     _load_retriever_if_index_exists,
     _generate_similarity_map,
+    _build_fast_plaid_index,
+    _load_fast_plaid_index_if_exists,
+    _search_fast_plaid,
+    _get_fast_plaid_image,
+    _get_fast_plaid_metadata,
     QwenVL,
 )
 
@@ -31,8 +43,33 @@ MODEL: str = "colqwen2"  # "colpali" or "colqwen2"
 
 # Data source: set to True to use the Hugging Face dataset example (recommended)
 USE_HF_DATASET: bool = True
+# Single dataset name (used when DATASET_NAMES is None)
 DATASET_NAME: str = "weaviate/arXiv-AI-papers-multi-vector"
-DATASET_SPLIT: str = "train"
+# Multiple datasets to combine (if provided, DATASET_NAME is ignored)
+# Can be:
+# - List of strings: ["dataset1", "dataset2"]
+# - List of tuples: [("dataset1", "config1"), ("dataset2", None)]  # None = no config needed
+# - Mixed: ["dataset1", ("dataset2", "config2")]
+#
+# Some potential datasets with images (may need IMAGE_FIELD_NAME adjustment):
+# - "weaviate/arXiv-AI-papers-multi-vector" (current, has "page_image" field)
+# - ("lmms-lab/DocVQA", "DocVQA") (has "image" field, document images, needs config)
+# - ("lmms-lab/DocVQA", "InfographicVQA") (has "image" field, infographic images)
+# - "pixparse/arxiv-papers" (if available, arXiv papers)
+# - "allenai/ai2d" (AI2D diagram dataset, has "image" field)
+# - "huggingface/document-images" (if available)
+# Note: Check dataset structure first - some may need IMAGE_FIELD_NAME specified
+# DATASET_NAMES: Optional[list[str | tuple[str, Optional[str]]]] = None
+DATASET_NAMES = [
+    "weaviate/arXiv-AI-papers-multi-vector",
+    ("lmms-lab/DocVQA", "DocVQA"),  # Specify config name for datasets with multiple configs
+]
+# Load multiple splits to get more data (e.g., ["train", "test", "validation"])
+# Set to None to try loading all available splits automatically
+DATASET_SPLITS: Optional[list[str]] = ["train", "test"]  # None = auto-detect all splits
+# Image field name in the dataset (auto-detect if None)
+# Common names: "page_image", "image", "images", "img"
+IMAGE_FIELD_NAME: Optional[str] = None  # None = auto-detect
 MAX_DOCS: Optional[int] = None  # limit number of pages to index; None = all
 
 # Local pages (used when USE_HF_DATASET == False)
@@ -40,10 +77,13 @@ PDF: Optional[str] = None  # e.g., "./pdfs/2004.12832v2.pdf"
 PAGES_DIR: str = "./pages"
 
 # Index + retrieval settings
-INDEX_PATH: str = "./indexes/colvision.leann"
+# Use a different index path for larger dataset to avoid overwriting existing index
+INDEX_PATH: str = "./indexes/colvision_large.leann"
+# Fast-Plaid index settings (alternative to LEANN index)
+# These are now command-line arguments (see CLI overrides section)
 TOPK: int = 3
 FIRST_STAGE_K: int = 500
-REBUILD_INDEX: bool = False
+REBUILD_INDEX: bool = True
 
 # Artifacts
 SAVE_TOP_IMAGE: Optional[str] = "./figures/retrieved_page.png"
@@ -54,38 +94,310 @@ ANSWER: bool = True
 MAX_NEW_TOKENS: int = 1024
 
 
+# %%
+# CLI overrides
+parser = argparse.ArgumentParser(description="Multi-vector LEANN similarity map demo")
+parser.add_argument(
+    "--search-method",
+    type=str,
+    choices=["ann", "exact", "exact-all"],
+    default="ann",
+    help="Which search method to use: 'ann' (fast ANN), 'exact' (ANN + exact rerank), or 'exact-all' (exact over all docs).",
+)
+parser.add_argument(
+    "--query",
+    type=str,
+    default=QUERY,
+    help=f"Query string to search for. Default: '{QUERY}'",
+)
+parser.add_argument(
+    "--use-fast-plaid",
+    action="store_true",
+    default=False,
+    help="Set to True to use fast-plaid instead of LEANN. Default: False",
+)
+parser.add_argument(
+    "--fast-plaid-index-path",
+    type=str,
+    default="./indexes/colvision_fastplaid",
+    help="Path to the Fast-Plaid index. Default: './indexes/colvision_fastplaid'",
+)
+parser.add_argument(
+    "--topk",
+    type=int,
+    default=TOPK,
+    help=f"Number of top results to retrieve. Default: {TOPK}",
+)
+cli_args, _unknown = parser.parse_known_args()
+SEARCH_METHOD: str = cli_args.search_method
+QUERY = cli_args.query  # Override QUERY with CLI argument if provided
+USE_FAST_PLAID: bool = cli_args.use_fast_plaid
+FAST_PLAID_INDEX_PATH: str = cli_args.fast_plaid_index_path
+TOPK: int = cli_args.topk  # Override TOPK with CLI argument if provided
+
 # %%
 
 # Step 1: Check if we can skip data loading (index already exists)
 retriever: Optional[Any] = None
+fast_plaid_index: Optional[Any] = None
 need_to_build_index = REBUILD_INDEX
 
-if not REBUILD_INDEX:
-    retriever = _load_retriever_if_index_exists(INDEX_PATH)
-    if retriever is not None:
-        print(f"✓ Index loaded from {INDEX_PATH}")
-        print(f"✓ Images available at: {retriever._images_dir_path()}")
-        need_to_build_index = False
+if USE_FAST_PLAID:
+    # Fast-Plaid index handling
+    if not REBUILD_INDEX:
+        try:
+            fast_plaid_index = _load_fast_plaid_index_if_exists(FAST_PLAID_INDEX_PATH)
+            if fast_plaid_index is not None:
+                print(f"✓ Fast-Plaid index found at {FAST_PLAID_INDEX_PATH}")
+                need_to_build_index = False
+            else:
+                print(f"Fast-Plaid index not found, will build new index")
+                need_to_build_index = True
+        except Exception as e:
+            # If loading fails (e.g., memory error, corrupted index), rebuild
+            print(f"Warning: Failed to load Fast-Plaid index: {e}")
+            print("Will rebuild the index...")
+            need_to_build_index = True
+            fast_plaid_index = None
     else:
-        print(f"Index not found, will build new index")
+        print(f"REBUILD_INDEX=True, will rebuild Fast-Plaid index")
+        need_to_build_index = True
+else:
+    # Original LEANN index handling
+    if not REBUILD_INDEX:
+        retriever = _load_retriever_if_index_exists(INDEX_PATH)
+        if retriever is not None:
+            print(f"✓ Index loaded from {INDEX_PATH}")
+            print(f"✓ Images available at: {retriever._images_dir_path()}")
+            need_to_build_index = False
+        else:
+            print(f"Index not found, will build new index")
+            need_to_build_index = True
+    else:
+        print(f"REBUILD_INDEX=True, will rebuild index")
         need_to_build_index = True
 
 # Step 2: Load data only if we need to build the index
 if need_to_build_index:
     print("Loading dataset...")
     if USE_HF_DATASET:
-        from datasets import load_dataset
+        from datasets import load_dataset, concatenate_datasets, DatasetDict
 
-        dataset = load_dataset(DATASET_NAME, split=DATASET_SPLIT)
+        # Determine which datasets to load
+        if DATASET_NAMES is not None:
+            dataset_names_to_load = DATASET_NAMES
+            print(f"Loading {len(dataset_names_to_load)} datasets: {dataset_names_to_load}")
+        else:
+            dataset_names_to_load = [DATASET_NAME]
+            print(f"Loading single dataset: {DATASET_NAME}")
+
+        # Load and combine datasets
+        all_datasets_to_concat = []
+
+        for dataset_entry in dataset_names_to_load:
+            # Handle both string and tuple formats
+            if isinstance(dataset_entry, tuple):
+                dataset_name, config_name = dataset_entry
+            else:
+                dataset_name = dataset_entry
+                config_name = None
+
+            print(f"\nProcessing dataset: {dataset_name}" + (f" (config: {config_name})" if config_name else ""))
+
+            # Load dataset to check available splits
+            # If config_name is provided, use it; otherwise try without config
+            try:
+                if config_name:
+                    dataset_dict = load_dataset(dataset_name, config_name)
+                else:
+                    dataset_dict = load_dataset(dataset_name)
+            except ValueError as e:
+                if "Config name is missing" in str(e):
+                    # Try to get available configs and suggest
+                    from datasets import get_dataset_config_names
+                    try:
+                        available_configs = get_dataset_config_names(dataset_name)
+                        raise ValueError(
+                            f"Dataset '{dataset_name}' requires a config name. "
+                            f"Available configs: {available_configs}. "
+                            f"Please specify as: ('{dataset_name}', 'config_name')"
+                        ) from e
+                    except Exception:
+                        raise ValueError(
+                            f"Dataset '{dataset_name}' requires a config name. "
+                            f"Please specify as: ('{dataset_name}', 'config_name')"
+                        ) from e
+                raise
+
+            # Determine which splits to load
+            if DATASET_SPLITS is None:
+                # Auto-detect: try to load all available splits
+                available_splits = list(dataset_dict.keys())
+                print(f"  Auto-detected splits: {available_splits}")
+                splits_to_load = available_splits
+            else:
+                splits_to_load = DATASET_SPLITS
+
+            # Load and concatenate multiple splits for this dataset
+            datasets_to_concat = []
+            for split in splits_to_load:
+                if split not in dataset_dict:
+                    print(f"  Warning: Split '{split}' not found in dataset. Available splits: {list(dataset_dict.keys())}")
+                    continue
+                split_dataset = dataset_dict[split]
+                print(f"  Loaded split '{split}': {len(split_dataset)} pages")
+                datasets_to_concat.append(split_dataset)
+
+            if not datasets_to_concat:
+                print(f"  Warning: No valid splits found for {dataset_name}. Skipping.")
+                continue
+
+            # Concatenate splits for this dataset
+            if len(datasets_to_concat) > 1:
+                combined_dataset = concatenate_datasets(datasets_to_concat)
+                print(f"  Concatenated {len(datasets_to_concat)} splits into {len(combined_dataset)} pages")
+            else:
+                combined_dataset = datasets_to_concat[0]
+
+            all_datasets_to_concat.append(combined_dataset)
+
+        if not all_datasets_to_concat:
+            raise RuntimeError("No valid datasets or splits found.")
+
+        # Concatenate all datasets
+        if len(all_datasets_to_concat) > 1:
+            dataset = concatenate_datasets(all_datasets_to_concat)
+            print(f"\nConcatenated {len(all_datasets_to_concat)} datasets into {len(dataset)} total pages")
+        else:
+            dataset = all_datasets_to_concat[0]
+
+        # Apply MAX_DOCS limit if specified
         N = len(dataset) if MAX_DOCS is None else min(MAX_DOCS, len(dataset))
+        if N < len(dataset):
+            print(f"Limiting to {N} pages (from {len(dataset)} total)")
+            dataset = dataset.select(range(N))
+
+        # Auto-detect image field name if not specified
+        if IMAGE_FIELD_NAME is None:
+            # Check multiple samples to find the most common image field
+            # (useful when datasets are merged and may have different field names)
+            possible_image_fields = ["page_image", "image", "images", "img", "page", "document_image"]
+            field_counts = {}
+
+            # Check first few samples to find image fields
+            num_samples_to_check = min(10, len(dataset))
+            for sample_idx in range(num_samples_to_check):
+                sample = dataset[sample_idx]
+                for field in possible_image_fields:
+                    if field in sample and sample[field] is not None:
+                        value = sample[field]
+                        if isinstance(value, Image.Image) or (hasattr(value, 'size') and hasattr(value, 'mode')):
+                            field_counts[field] = field_counts.get(field, 0) + 1
+
+            # Choose the most common field, or first found if tied
+            if field_counts:
+                image_field = max(field_counts.items(), key=lambda x: x[1])[0]
+                print(f"Auto-detected image field: '{image_field}' (found in {field_counts[image_field]}/{num_samples_to_check} samples)")
+            else:
+                # Fallback: check first sample only
+                sample = dataset[0]
+                image_field = None
+                for field in possible_image_fields:
+                    if field in sample:
+                        value = sample[field]
+                        if isinstance(value, Image.Image) or (hasattr(value, 'size') and hasattr(value, 'mode')):
+                            image_field = field
+                            break
+                if image_field is None:
+                    raise RuntimeError(
+                        f"Could not auto-detect image field. Available fields: {list(sample.keys())}. "
+                        f"Please specify IMAGE_FIELD_NAME manually."
+                    )
+                print(f"Auto-detected image field: '{image_field}'")
+        else:
+            image_field = IMAGE_FIELD_NAME
+            if image_field not in dataset[0]:
+                raise RuntimeError(
+                    f"Image field '{image_field}' not found. Available fields: {list(dataset[0].keys())}"
+                )
+
         filepaths: list[str] = []
         images: list[Image.Image] = []
-        for i in tqdm(range(N), desc="Loading dataset", total=N):
+        for i in tqdm(range(len(dataset)), desc="Loading dataset", total=len(dataset)):
             p = dataset[i]
-            # Compose a descriptive identifier for printing later
-            identifier = f"arXiv:{p['paper_arxiv_id']}|title:{p['paper_title']}|page:{int(p['page_number'])}|id:{p['page_id']}"
+            # Try to compose a descriptive identifier
+            # Handle different dataset structures
+            identifier_parts = []
+
+            # Helper function to safely get field value
+            def safe_get(field_name, default=None):
+                if field_name in p and p[field_name] is not None:
+                    return p[field_name]
+                return default
+
+            # Try to get various identifier fields
+            if safe_get("paper_arxiv_id"):
+                identifier_parts.append(f"arXiv:{p['paper_arxiv_id']}")
+            if safe_get("paper_title"):
+                identifier_parts.append(f"title:{p['paper_title']}")
+            if safe_get("page_number") is not None:
+                try:
+                    identifier_parts.append(f"page:{int(p['page_number'])}")
+                except (ValueError, TypeError):
+                    # If conversion fails, use the raw value or skip
+                    if p['page_number']:
+                        identifier_parts.append(f"page:{p['page_number']}")
+            if safe_get("page_id"):
+                identifier_parts.append(f"id:{p['page_id']}")
+            elif safe_get("questionId"):
+                identifier_parts.append(f"qid:{p['questionId']}")
+            elif safe_get("docId"):
+                identifier_parts.append(f"docId:{p['docId']}")
+            elif safe_get("id"):
+                identifier_parts.append(f"id:{p['id']}")
+
+            # If no identifier parts found, create one from index
+            if identifier_parts:
+                identifier = "|".join(identifier_parts)
+            else:
+                # Create identifier from available fields or index
+                fallback_parts = []
+                # Try common fields that might exist
+                for field in ["ucsf_document_id", "docId", "questionId", "id"]:
+                    if safe_get(field):
+                        fallback_parts.append(f"{field}:{p[field]}")
+                        break
+                if fallback_parts:
+                    identifier = "|".join(fallback_parts) + f"|idx:{i}"
+                else:
+                    identifier = f"doc_{i}"
+
             filepaths.append(identifier)
-            images.append(p["page_image"])  # PIL Image
+
+            # Get image - try detected field first, then fallback to other common fields
+            img = None
+            if image_field in p and p[image_field] is not None:
+                img = p[image_field]
+            else:
+                # Fallback: try other common image field names
+                for fallback_field in ["image", "page_image", "images", "img"]:
+                    if fallback_field in p and p[fallback_field] is not None:
+                        img = p[fallback_field]
+                        break
+
+            if img is None:
+                raise RuntimeError(
+                    f"No image found for sample {i}. Available fields: {list(p.keys())}. "
+                    f"Expected field: {image_field}"
+                )
+
+            # Ensure it's a PIL Image
+            if not isinstance(img, Image.Image):
+                if hasattr(img, 'convert'):
+                    img = img.convert('RGB')
+                else:
+                    img = Image.fromarray(img) if hasattr(img, '__array__') else Image.open(img)
+            images.append(img)
     else:
         _maybe_convert_pdf_to_images(PDF, PAGES_DIR)
         filepaths, images = _load_images_from_dir(PAGES_DIR)
@@ -94,6 +406,19 @@ if need_to_build_index:
                 f"No images found in {PAGES_DIR}. Provide PDF path in PDF variable or ensure images exist."
             )
     print(f"Loaded {len(images)} images")
+
+    # Memory check before loading model
+    try:
+        import psutil
+        import torch
+        process = psutil.Process(os.getpid())
+        mem_info = process.memory_info()
+        print(f"Memory usage after loading images: {mem_info.rss / 1024 / 1024 / 1024:.2f} GB")
+        if torch.cuda.is_available():
+            print(f"GPU memory allocated: {torch.cuda.memory_allocated() / 1024**3:.2f} GB")
+            print(f"GPU memory reserved: {torch.cuda.memory_reserved() / 1024**3:.2f} GB")
+    except ImportError:
+        pass
 else:
     print("Skipping dataset loading (using existing index)")
     filepaths = []  # Not needed when using existing index
@@ -102,46 +427,181 @@ else:
 
 # %%
 # Step 3: Load model and processor (only if we need to build index or perform search)
-model_name, model, processor, device_str, device, dtype = _load_colvision(MODEL)
-print(f"Using model={model_name}, device={device_str}, dtype={dtype}")
+print("Step 3: Loading model and processor...")
+print(f"  Model: {MODEL}")
+try:
+    import sys
+    print(f"  Python version: {sys.version}")
+    print(f"  Python executable: {sys.executable}")
+
+    model_name, model, processor, device_str, device, dtype = _load_colvision(MODEL)
+    print(f"✓ Using model={model_name}, device={device_str}, dtype={dtype}")
+
+    # Memory check after loading model
+    try:
+        import psutil
+        import torch
+        process = psutil.Process(os.getpid())
+        mem_info = process.memory_info()
+        print(f"  Memory usage after loading model: {mem_info.rss / 1024 / 1024 / 1024:.2f} GB")
+        if torch.cuda.is_available():
+            print(f"  GPU memory allocated: {torch.cuda.memory_allocated() / 1024**3:.2f} GB")
+            print(f"  GPU memory reserved: {torch.cuda.memory_reserved() / 1024**3:.2f} GB")
+    except ImportError:
+        pass
+except Exception as e:
+    print(f"✗ Error loading model: {type(e).__name__}: {e}")
+    import traceback
+    traceback.print_exc()
+    raise
 
 
 # %%
 
 # %%
 # Step 4: Build index if needed
-if need_to_build_index and retriever is None:
-    print("Building index...")
-    doc_vecs = _embed_images(model, processor, images)
-    retriever = _build_index(INDEX_PATH, doc_vecs, filepaths, images)
-    print(f"✓ Index built and images saved to: {retriever._images_dir_path()}")
-    # Clear memory
-    del images, filepaths, doc_vecs
+if need_to_build_index:
+    print("Step 4: Building index...")
+    print(f"  Number of images: {len(images)}")
+    print(f"  Number of filepaths: {len(filepaths)}")
 
-# Note: Images are now stored in the index, retriever will load them on-demand from disk
+    try:
+        print("  Embedding images...")
+        doc_vecs = _embed_images(model, processor, images)
+        print(f"  Embedded {len(doc_vecs)} documents")
+        print(f"  First doc vec shape: {doc_vecs[0].shape if len(doc_vecs) > 0 else 'N/A'}")
+    except Exception as e:
+        print(f"Error embedding images: {type(e).__name__}: {e}")
+        import traceback
+        traceback.print_exc()
+        raise
+
+    if USE_FAST_PLAID:
+        # Build Fast-Plaid index
+        print("  Building Fast-Plaid index...")
+        try:
+            fast_plaid_index, build_secs = _build_fast_plaid_index(
+                FAST_PLAID_INDEX_PATH, doc_vecs, filepaths, images
+            )
+            from pathlib import Path
+            print(f"✓ Fast-Plaid index built in {build_secs:.3f}s")
+            print(f"✓ Index saved to: {FAST_PLAID_INDEX_PATH}")
+            print(f"✓ Images saved to: {Path(FAST_PLAID_INDEX_PATH) / 'images'}")
+        except Exception as e:
+            print(f"Error building Fast-Plaid index: {type(e).__name__}: {e}")
+            import traceback
+            traceback.print_exc()
+            raise
+        finally:
+            # Clear memory
+            print("  Clearing memory...")
+            del images, filepaths, doc_vecs
+    else:
+        # Build original LEANN index
+        try:
+            retriever = _build_index(INDEX_PATH, doc_vecs, filepaths, images)
+            print(f"✓ Index built and images saved to: {retriever._images_dir_path()}")
+        except Exception as e:
+            print(f"Error building LEANN index: {type(e).__name__}: {e}")
+            import traceback
+            traceback.print_exc()
+            raise
+        finally:
+            # Clear memory
+            print("  Clearing memory...")
+            del images, filepaths, doc_vecs
+
+# Note: Images are now stored separately, retriever/fast_plaid_index will reference them
 
 
 # %%
 # Step 5: Embed query and search
+_t0 = time.perf_counter()
 q_vec = _embed_queries(model, processor, [QUERY])[0]
-results = retriever.search(q_vec.float().numpy(), topk=TOPK)
+query_embed_secs = time.perf_counter() - _t0
+
+print(f"[Search] Method: {SEARCH_METHOD}")
+print(f"[Timing] Query embedding: {query_embed_secs:.3f}s")
+
+# Run the selected search method and time it
+if USE_FAST_PLAID:
+    # Fast-Plaid search
+    if fast_plaid_index is None:
+        fast_plaid_index = _load_fast_plaid_index_if_exists(FAST_PLAID_INDEX_PATH)
+        if fast_plaid_index is None:
+            raise RuntimeError(f"Fast-Plaid index not found at {FAST_PLAID_INDEX_PATH}")
+
+    results, search_secs = _search_fast_plaid(fast_plaid_index, q_vec, TOPK)
+    print(f"[Timing] Fast-Plaid Search: {search_secs:.3f}s")
+else:
+    # Original LEANN search
+    query_np = q_vec.float().numpy()
+
+    if SEARCH_METHOD == "ann":
+        results = retriever.search(query_np, topk=TOPK, first_stage_k=FIRST_STAGE_K)
+        search_secs = time.perf_counter() - _t0
+        print(f"[Timing] Search (ANN): {search_secs:.3f}s (first_stage_k={FIRST_STAGE_K})")
+    elif SEARCH_METHOD == "exact":
+        results = retriever.search_exact(query_np, topk=TOPK, first_stage_k=FIRST_STAGE_K)
+        search_secs = time.perf_counter() - _t0
+        print(f"[Timing] Search (Exact rerank): {search_secs:.3f}s (first_stage_k={FIRST_STAGE_K})")
+    elif SEARCH_METHOD == "exact-all":
+        results = retriever.search_exact_all(query_np, topk=TOPK)
+        search_secs = time.perf_counter() - _t0
+        print(f"[Timing] Search (Exact all): {search_secs:.3f}s")
+    else:
+        results = []
 if not results:
     print("No results found.")
 else:
     print(f'Top {len(results)} results for query: "{QUERY}"')
+    print("\n[DEBUG] Retrieval details:")
     top_images: list[Image.Image] = []
-    for rank, (score, doc_id) in enumerate(results, start=1):
-        # Retrieve image from index instead of memory
-        image = retriever.get_image(doc_id)
-        if image is None:
-            print(f"Warning: Could not retrieve image for doc_id {doc_id}")
-            continue
+    image_hashes = {}  # Track image hashes to detect duplicates
 
-        metadata = retriever.get_metadata(doc_id)
-        path = metadata.get("filepath", "unknown") if metadata else "unknown"
-        # For HF dataset, path is a descriptive identifier, not a real file path
-        print(f"{rank}) MaxSim: {score:.4f}, Page: {path}")
-        top_images.append(image)
+    for rank, (score, doc_id) in enumerate(results, start=1):
+        # Retrieve image and metadata based on index type
+        if USE_FAST_PLAID:
+            # Fast-Plaid: load image and get metadata
+            image = _get_fast_plaid_image(FAST_PLAID_INDEX_PATH, doc_id)
+            if image is None:
+                print(f"Warning: Could not find image for doc_id {doc_id}")
+                continue
+
+            metadata = _get_fast_plaid_metadata(FAST_PLAID_INDEX_PATH, doc_id)
+            path = metadata.get("filepath", f"doc_{doc_id}") if metadata else f"doc_{doc_id}"
+            top_images.append(image)
+        else:
+            # Original LEANN: retrieve from retriever
+            image = retriever.get_image(doc_id)
+            if image is None:
+                print(f"Warning: Could not retrieve image for doc_id {doc_id}")
+                continue
+
+            metadata = retriever.get_metadata(doc_id)
+            path = metadata.get("filepath", "unknown") if metadata else "unknown"
+            top_images.append(image)
+
+        # Calculate image hash to detect duplicates
+        import hashlib
+        import io
+        # Convert image to bytes for hashing
+        img_bytes = io.BytesIO()
+        image.save(img_bytes, format='PNG')
+        image_bytes = img_bytes.getvalue()
+        image_hash = hashlib.md5(image_bytes).hexdigest()[:8]
+
+        # Check if this image was already seen
+        duplicate_info = ""
+        if image_hash in image_hashes:
+            duplicate_info = f" [DUPLICATE of rank {image_hashes[image_hash]}]"
+        else:
+            image_hashes[image_hash] = rank
+
+        # Print detailed information
+        print(f"{rank}) doc_id={doc_id}, MaxSim={score:.4f}, Page={path}, ImageHash={image_hash}{duplicate_info}")
+        if metadata:
+            print(f"   Metadata: {metadata}")
 
     if SAVE_TOP_IMAGE:
         from pathlib import Path as _Path
@@ -204,6 +664,9 @@ if results and SIMILARITY_MAP:
 # Step 7: Optional answer generation
 if results and ANSWER:
     qwen = QwenVL(device=device_str)
+    _t0 = time.perf_counter()
     response = qwen.answer(QUERY, top_images[:TOPK], max_new_tokens=MAX_NEW_TOKENS)
+    gen_secs = time.perf_counter() - _t0
+    print(f"[Timing] Generation: {gen_secs:.3f}s")
     print("\nAnswer:")
     print(response)

apps/multimodal/vision-based-pdf-multi-vector/vidore_v1_benchmark.py

@@ -0,0 +1,448 @@
+#!/usr/bin/env python3
+"""
+Modular script to reproduce NDCG results for ViDoRe v1 benchmark.
+
+This script uses the interface from leann_multi_vector.py to:
+1. Download ViDoRe v1 datasets
+2. Build indexes (LEANN or Fast-Plaid)
+3. Perform retrieval
+4. Evaluate using NDCG metrics
+
+Usage:
+    # Evaluate all ViDoRe v1 tasks
+    python vidore_v1_benchmark.py --model colqwen2 --tasks all
+
+    # Evaluate specific task
+    python vidore_v1_benchmark.py --model colqwen2 --task VidoreArxivQARetrieval
+
+    # Use Fast-Plaid index
+    python vidore_v1_benchmark.py --model colqwen2 --use-fast-plaid --fast-plaid-index-path ./indexes/vidore_fastplaid
+
+    # Rebuild index
+    python vidore_v1_benchmark.py --model colqwen2 --rebuild-index
+"""
+
+import argparse
+import json
+import os
+from typing import Optional
+
+from datasets import load_dataset
+from leann_multi_vector import (
+    ViDoReBenchmarkEvaluator,
+    _ensure_repo_paths_importable,
+)
+
+_ensure_repo_paths_importable(__file__)
+
+# ViDoRe v1 task configurations
+# Prompts match MTEB task metadata prompts
+VIDORE_V1_TASKS = {
+    "VidoreArxivQARetrieval": {
+        "dataset_path": "vidore/arxivqa_test_subsampled_beir",
+        "revision": "7d94d570960eac2408d3baa7a33f9de4822ae3e4",
+        "prompt": {"query": "Find a screenshot that relevant to the user's question."},
+    },
+    "VidoreDocVQARetrieval": {
+        "dataset_path": "vidore/docvqa_test_subsampled_beir",
+        "revision": "162ba2fc1a8437eda8b6c37b240bc1c0f0deb092",
+        "prompt": {"query": "Find a screenshot that relevant to the user's question."},
+    },
+    "VidoreInfoVQARetrieval": {
+        "dataset_path": "vidore/infovqa_test_subsampled_beir",
+        "revision": "b802cc5fd6c605df2d673a963667d74881d2c9a4",
+        "prompt": {"query": "Find a screenshot that relevant to the user's question."},
+    },
+    "VidoreTabfquadRetrieval": {
+        "dataset_path": "vidore/tabfquad_test_subsampled_beir",
+        "revision": "61a2224bcd29b7b261a4892ff4c8bea353527a31",
+        "prompt": {"query": "Find a screenshot that relevant to the user's question."},
+    },
+    "VidoreTatdqaRetrieval": {
+        "dataset_path": "vidore/tatdqa_test_beir",
+        "revision": "5feb5630fdff4d8d189ffedb2dba56862fdd45c0",
+        "prompt": {"query": "Find a screenshot that relevant to the user's question."},
+    },
+    "VidoreShiftProjectRetrieval": {
+        "dataset_path": "vidore/shiftproject_test_beir",
+        "revision": "84a382e05c4473fed9cff2bbae95fe2379416117",
+        "prompt": {"query": "Find a screenshot that relevant to the user's question."},
+    },
+    "VidoreSyntheticDocQAAIRetrieval": {
+        "dataset_path": "vidore/syntheticDocQA_artificial_intelligence_test_beir",
+        "revision": "2d9ebea5a1c6e9ef4a3b902a612f605dca11261c",
+        "prompt": {"query": "Find a screenshot that relevant to the user's question."},
+    },
+    "VidoreSyntheticDocQAEnergyRetrieval": {
+        "dataset_path": "vidore/syntheticDocQA_energy_test_beir",
+        "revision": "9935aadbad5c8deec30910489db1b2c7133ae7a7",
+        "prompt": {"query": "Find a screenshot that relevant to the user's question."},
+    },
+    "VidoreSyntheticDocQAGovernmentReportsRetrieval": {
+        "dataset_path": "vidore/syntheticDocQA_government_reports_test_beir",
+        "revision": "b4909afa930f81282fd20601e860668073ad02aa",
+        "prompt": {"query": "Find a screenshot that relevant to the user's question."},
+    },
+    "VidoreSyntheticDocQAHealthcareIndustryRetrieval": {
+        "dataset_path": "vidore/syntheticDocQA_healthcare_industry_test_beir",
+        "revision": "f9e25d5b6e13e1ad9f5c3cce202565031b3ab164",
+        "prompt": {"query": "Find a screenshot that relevant to the user's question."},
+    },
+}
+
+# Task name aliases (short names -> full names)
+TASK_ALIASES = {
+    "arxivqa": "VidoreArxivQARetrieval",
+    "docvqa": "VidoreDocVQARetrieval",
+    "infovqa": "VidoreInfoVQARetrieval",
+    "tabfquad": "VidoreTabfquadRetrieval",
+    "tatdqa": "VidoreTatdqaRetrieval",
+    "shiftproject": "VidoreShiftProjectRetrieval",
+    "syntheticdocqa_ai": "VidoreSyntheticDocQAAIRetrieval",
+    "syntheticdocqa_energy": "VidoreSyntheticDocQAEnergyRetrieval",
+    "syntheticdocqa_government": "VidoreSyntheticDocQAGovernmentReportsRetrieval",
+    "syntheticdocqa_healthcare": "VidoreSyntheticDocQAHealthcareIndustryRetrieval",
+}
+
+
+def normalize_task_name(task_name: str) -> str:
+    """Normalize task name (handle aliases)."""
+    task_name_lower = task_name.lower()
+    if task_name in VIDORE_V1_TASKS:
+        return task_name
+    if task_name_lower in TASK_ALIASES:
+        return TASK_ALIASES[task_name_lower]
+    # Try partial match
+    for alias, full_name in TASK_ALIASES.items():
+        if alias in task_name_lower or task_name_lower in alias:
+            return full_name
+    return task_name
+
+
+def get_safe_model_name(model_name: str) -> str:
+    """Get a safe model name for use in file paths."""
+    import hashlib
+    import os
+
+    # If it's a path, use basename or hash
+    if os.path.exists(model_name) and os.path.isdir(model_name):
+        # Use basename if it's reasonable, otherwise use hash
+        basename = os.path.basename(model_name.rstrip("/"))
+        if basename and len(basename) < 100 and not basename.startswith("."):
+            return basename
+        # Use hash for very long or problematic paths
+        return hashlib.md5(model_name.encode()).hexdigest()[:16]
+    # For HuggingFace model names, replace / with _
+    return model_name.replace("/", "_").replace(":", "_")
+
+
+def load_vidore_v1_data(
+    dataset_path: str,
+    revision: Optional[str] = None,
+    split: str = "test",
+):
+    """
+    Load ViDoRe v1 dataset.
+
+    Returns:
+        corpus: dict mapping corpus_id to PIL Image
+        queries: dict mapping query_id to query text
+        qrels: dict mapping query_id to dict of {corpus_id: relevance_score}
+    """
+    print(f"Loading dataset: {dataset_path} (split={split})")
+
+    # Load queries
+    query_ds = load_dataset(dataset_path, "queries", split=split, revision=revision)
+
+    queries = {}
+    for row in query_ds:
+        query_id = f"query-{split}-{row['query-id']}"
+        queries[query_id] = row["query"]
+
+    # Load corpus (images)
+    corpus_ds = load_dataset(dataset_path, "corpus", split=split, revision=revision)
+
+    corpus = {}
+    for row in corpus_ds:
+        corpus_id = f"corpus-{split}-{row['corpus-id']}"
+        # Extract image from the dataset row
+        if "image" in row:
+            corpus[corpus_id] = row["image"]
+        elif "page_image" in row:
+            corpus[corpus_id] = row["page_image"]
+        else:
+            raise ValueError(
+                f"No image field found in corpus. Available fields: {list(row.keys())}"
+            )
+
+    # Load qrels (relevance judgments)
+    qrels_ds = load_dataset(dataset_path, "qrels", split=split, revision=revision)
+
+    qrels = {}
+    for row in qrels_ds:
+        query_id = f"query-{split}-{row['query-id']}"
+        corpus_id = f"corpus-{split}-{row['corpus-id']}"
+        if query_id not in qrels:
+            qrels[query_id] = {}
+        qrels[query_id][corpus_id] = int(row["score"])
+
+    print(
+        f"Loaded {len(queries)} queries, {len(corpus)} corpus items, {len(qrels)} query-relevance mappings"
+    )
+
+    # Filter qrels to only include queries that exist
+    qrels = {qid: rel_docs for qid, rel_docs in qrels.items() if qid in queries}
+
+    # Filter out queries without any relevant documents (matching MTEB behavior)
+    # This is important for correct NDCG calculation
+    qrels_filtered = {qid: rel_docs for qid, rel_docs in qrels.items() if len(rel_docs) > 0}
+    queries_filtered = {
+        qid: query_text for qid, query_text in queries.items() if qid in qrels_filtered
+    }
+
+    print(
+        f"After filtering queries without positives: {len(queries_filtered)} queries, {len(qrels_filtered)} query-relevance mappings"
+    )
+
+    return corpus, queries_filtered, qrels_filtered
+
+
+def evaluate_task(
+    task_name: str,
+    model_name: str,
+    index_path: str,
+    use_fast_plaid: bool = False,
+    fast_plaid_index_path: Optional[str] = None,
+    rebuild_index: bool = False,
+    top_k: int = 1000,
+    first_stage_k: int = 500,
+    k_values: Optional[list[int]] = None,
+    output_dir: Optional[str] = None,
+):
+    """
+    Evaluate a single ViDoRe v1 task.
+    """
+    print(f"\n{'=' * 80}")
+    print(f"Evaluating task: {task_name}")
+    print(f"{'=' * 80}")
+
+    # Normalize task name (handle aliases)
+    task_name = normalize_task_name(task_name)
+
+    # Get task config
+    if task_name not in VIDORE_V1_TASKS:
+        raise ValueError(f"Unknown task: {task_name}. Available: {list(VIDORE_V1_TASKS.keys())}")
+
+    task_config = VIDORE_V1_TASKS[task_name]
+    dataset_path = task_config["dataset_path"]
+    revision = task_config["revision"]
+
+    # Load data
+    corpus, queries, qrels = load_vidore_v1_data(
+        dataset_path=dataset_path,
+        revision=revision,
+        split="test",
+    )
+
+    # Initialize k_values if not provided
+    if k_values is None:
+        k_values = [1, 3, 5, 10, 20, 100, 1000]
+
+    # Check if we have any queries
+    if len(queries) == 0:
+        print(f"\nWarning: No queries found for task {task_name}. Skipping evaluation.")
+        # Return zero scores
+        scores = {}
+        for k in k_values:
+            scores[f"ndcg_at_{k}"] = 0.0
+            scores[f"map_at_{k}"] = 0.0
+            scores[f"recall_at_{k}"] = 0.0
+            scores[f"precision_at_{k}"] = 0.0
+            scores[f"mrr_at_{k}"] = 0.0
+        return scores
+
+    # Initialize evaluator
+    evaluator = ViDoReBenchmarkEvaluator(
+        model_name=model_name,
+        use_fast_plaid=use_fast_plaid,
+        top_k=top_k,
+        first_stage_k=first_stage_k,
+        k_values=k_values,
+    )
+
+    # Build or load index
+    # Use safe model name for index path (different models need different indexes)
+    safe_model_name = get_safe_model_name(model_name)
+    index_path_full = index_path if not use_fast_plaid else fast_plaid_index_path
+    if index_path_full is None:
+        index_path_full = f"./indexes/{task_name}_{safe_model_name}"
+        if use_fast_plaid:
+            index_path_full = f"./indexes/{task_name}_{safe_model_name}_fastplaid"
+
+    index_or_retriever, corpus_ids_ordered = evaluator.build_index_from_corpus(
+        corpus=corpus,
+        index_path=index_path_full,
+        rebuild=rebuild_index,
+    )
+
+    # Search queries
+    task_prompt = task_config.get("prompt")
+    results = evaluator.search_queries(
+        queries=queries,
+        corpus_ids=corpus_ids_ordered,
+        index_or_retriever=index_or_retriever,
+        fast_plaid_index_path=fast_plaid_index_path,
+        task_prompt=task_prompt,
+    )
+
+    # Evaluate
+    scores = evaluator.evaluate_results(results, qrels, k_values=k_values)
+
+    # Print results
+    print(f"\n{'=' * 80}")
+    print(f"Results for {task_name}:")
+    print(f"{'=' * 80}")
+    for metric, value in scores.items():
+        if isinstance(value, (int, float)):
+            print(f"  {metric}: {value:.5f}")
+
+    # Save results
+    if output_dir:
+        os.makedirs(output_dir, exist_ok=True)
+        results_file = os.path.join(output_dir, f"{task_name}_results.json")
+        scores_file = os.path.join(output_dir, f"{task_name}_scores.json")
+
+        with open(results_file, "w") as f:
+            json.dump(results, f, indent=2)
+        print(f"\nSaved results to: {results_file}")
+
+        with open(scores_file, "w") as f:
+            json.dump(scores, f, indent=2)
+        print(f"Saved scores to: {scores_file}")
+
+    return scores
+
+
+def main():
+    parser = argparse.ArgumentParser(
+        description="Evaluate ViDoRe v1 benchmark using LEANN/Fast-Plaid indexing"
+    )
+    parser.add_argument(
+        "--model",
+        type=str,
+        default="colqwen2",
+        help="Model to use: 'colqwen2', 'colpali', or path to a model directory (supports LoRA adapters)",
+    )
+    parser.add_argument(
+        "--task",
+        type=str,
+        default=None,
+        help="Specific task to evaluate (or 'all' for all tasks)",
+    )
+    parser.add_argument(
+        "--tasks",
+        type=str,
+        default="all",
+        help="Tasks to evaluate: 'all' or comma-separated list",
+    )
+    parser.add_argument(
+        "--index-path",
+        type=str,
+        default=None,
+        help="Path to LEANN index (auto-generated if not provided)",
+    )
+    parser.add_argument(
+        "--use-fast-plaid",
+        action="store_true",
+        help="Use Fast-Plaid instead of LEANN",
+    )
+    parser.add_argument(
+        "--fast-plaid-index-path",
+        type=str,
+        default=None,
+        help="Path to Fast-Plaid index (auto-generated if not provided)",
+    )
+    parser.add_argument(
+        "--rebuild-index",
+        action="store_true",
+        help="Rebuild index even if it exists",
+    )
+    parser.add_argument(
+        "--top-k",
+        type=int,
+        default=1000,
+        help="Top-k results to retrieve (MTEB default is max(k_values)=1000)",
+    )
+    parser.add_argument(
+        "--first-stage-k",
+        type=int,
+        default=500,
+        help="First stage k for LEANN search",
+    )
+    parser.add_argument(
+        "--k-values",
+        type=str,
+        default="1,3,5,10,20,100,1000",
+        help="Comma-separated k values for evaluation (e.g., '1,3,5,10,100')",
+    )
+    parser.add_argument(
+        "--output-dir",
+        type=str,
+        default="./vidore_v1_results",
+        help="Output directory for results",
+    )
+
+    args = parser.parse_args()
+
+    # Parse k_values
+    k_values = [int(k.strip()) for k in args.k_values.split(",")]
+
+    # Determine tasks to evaluate
+    if args.task:
+        tasks_to_eval = [normalize_task_name(args.task)]
+    elif args.tasks.lower() == "all":
+        tasks_to_eval = list(VIDORE_V1_TASKS.keys())
+    else:
+        tasks_to_eval = [normalize_task_name(t.strip()) for t in args.tasks.split(",")]
+
+    print(f"Tasks to evaluate: {tasks_to_eval}")
+
+    # Evaluate each task
+    all_scores = {}
+    for task_name in tasks_to_eval:
+        try:
+            scores = evaluate_task(
+                task_name=task_name,
+                model_name=args.model,
+                index_path=args.index_path,
+                use_fast_plaid=args.use_fast_plaid,
+                fast_plaid_index_path=args.fast_plaid_index_path,
+                rebuild_index=args.rebuild_index,
+                top_k=args.top_k,
+                first_stage_k=args.first_stage_k,
+                k_values=k_values,
+                output_dir=args.output_dir,
+            )
+            all_scores[task_name] = scores
+        except Exception as e:
+            print(f"\nError evaluating {task_name}: {e}")
+            import traceback
+
+            traceback.print_exc()
+            continue
+
+    # Print summary
+    if all_scores:
+        print(f"\n{'=' * 80}")
+        print("SUMMARY")
+        print(f"{'=' * 80}")
+        for task_name, scores in all_scores.items():
+            print(f"\n{task_name}:")
+            # Print main metrics
+            for metric in ["ndcg_at_5", "ndcg_at_10", "ndcg_at_100", "map_at_10", "recall_at_10"]:
+                if metric in scores:
+                    print(f"  {metric}: {scores[metric]:.5f}")
+
+
+if __name__ == "__main__":
+    main()

apps/multimodal/vision-based-pdf-multi-vector/vidore_v2_benchmark.py

@@ -0,0 +1,439 @@
+#!/usr/bin/env python3
+"""
+Modular script to reproduce NDCG results for ViDoRe v2 benchmark.
+
+This script uses the interface from leann_multi_vector.py to:
+1. Download ViDoRe v2 datasets
+2. Build indexes (LEANN or Fast-Plaid)
+3. Perform retrieval
+4. Evaluate using NDCG metrics
+
+Usage:
+    # Evaluate all ViDoRe v2 tasks
+    python vidore_v2_benchmark.py --model colqwen2 --tasks all
+
+    # Evaluate specific task
+    python vidore_v2_benchmark.py --model colqwen2 --task Vidore2ESGReportsRetrieval
+
+    # Use Fast-Plaid index
+    python vidore_v2_benchmark.py --model colqwen2 --use-fast-plaid --fast-plaid-index-path ./indexes/vidore_fastplaid
+
+    # Rebuild index
+    python vidore_v2_benchmark.py --model colqwen2 --rebuild-index
+"""
+
+import argparse
+import json
+import os
+from typing import Optional
+
+from datasets import load_dataset
+from leann_multi_vector import (
+    ViDoReBenchmarkEvaluator,
+    _ensure_repo_paths_importable,
+)
+
+_ensure_repo_paths_importable(__file__)
+
+# Language name to dataset language field value mapping
+# Dataset uses ISO 639-3 + ISO 15924 format (e.g., "eng-Latn")
+LANGUAGE_MAPPING = {
+    "english": "eng-Latn",
+    "french": "fra-Latn",
+    "spanish": "spa-Latn",
+    "german": "deu-Latn",
+}
+
+# ViDoRe v2 task configurations
+# Prompts match MTEB task metadata prompts
+VIDORE_V2_TASKS = {
+    "Vidore2ESGReportsRetrieval": {
+        "dataset_path": "vidore/esg_reports_v2",
+        "revision": "0542c0d03da0ec1c8cbc517c8d78e7e95c75d3d3",
+        "languages": ["french", "spanish", "english", "german"],
+        "prompt": {"query": "Find a screenshot that relevant to the user's question."},
+    },
+    "Vidore2EconomicsReportsRetrieval": {
+        "dataset_path": "vidore/economics_reports_v2",
+        "revision": "b3e3a04b07fbbaffe79be49dabf92f691fbca252",
+        "languages": ["french", "spanish", "english", "german"],
+        "prompt": {"query": "Find a screenshot that relevant to the user's question."},
+    },
+    "Vidore2BioMedicalLecturesRetrieval": {
+        "dataset_path": "vidore/biomedical_lectures_v2",
+        "revision": "a29202f0da409034d651614d87cd8938d254e2ea",
+        "languages": ["french", "spanish", "english", "german"],
+        "prompt": {"query": "Find a screenshot that relevant to the user's question."},
+    },
+    "Vidore2ESGReportsHLRetrieval": {
+        "dataset_path": "vidore/esg_reports_human_labeled_v2",
+        "revision": "6d467dedb09a75144ede1421747e47cf036857dd",
+        # Note: This dataset doesn't have language filtering - all queries are English
+        "languages": None,  # No language filtering needed
+        "prompt": {"query": "Find a screenshot that relevant to the user's question."},
+    },
+}
+
+
+def load_vidore_v2_data(
+    dataset_path: str,
+    revision: Optional[str] = None,
+    split: str = "test",
+    language: Optional[str] = None,
+):
+    """
+    Load ViDoRe v2 dataset.
+
+    Returns:
+        corpus: dict mapping corpus_id to PIL Image
+        queries: dict mapping query_id to query text
+        qrels: dict mapping query_id to dict of {corpus_id: relevance_score}
+    """
+    print(f"Loading dataset: {dataset_path} (split={split}, language={language})")
+
+    # Load queries
+    query_ds = load_dataset(dataset_path, "queries", split=split, revision=revision)
+
+    # Check if dataset has language field before filtering
+    has_language_field = len(query_ds) > 0 and "language" in query_ds.column_names
+
+    if language and has_language_field:
+        # Map language name to dataset language field value (e.g., "english" -> "eng-Latn")
+        dataset_language = LANGUAGE_MAPPING.get(language, language)
+        query_ds_filtered = query_ds.filter(lambda x: x.get("language") == dataset_language)
+        # Check if filtering resulted in empty dataset
+        if len(query_ds_filtered) == 0:
+            print(
+                f"Warning: No queries found after filtering by language '{language}' (mapped to '{dataset_language}')."
+            )
+            # Try with original language value (dataset might use simple names like 'english')
+            print(f"Trying with original language value '{language}'...")
+            query_ds_filtered = query_ds.filter(lambda x: x.get("language") == language)
+            if len(query_ds_filtered) == 0:
+                # Try to get a sample to see actual language values
+                try:
+                    sample_ds = load_dataset(
+                        dataset_path, "queries", split=split, revision=revision
+                    )
+                    if len(sample_ds) > 0 and "language" in sample_ds.column_names:
+                        sample_langs = set(sample_ds["language"])
+                        print(f"Available language values in dataset: {sample_langs}")
+                except Exception:
+                    pass
+            else:
+                print(
+                    f"Found {len(query_ds_filtered)} queries using original language value '{language}'"
+                )
+        query_ds = query_ds_filtered
+
+    queries = {}
+    for row in query_ds:
+        query_id = f"query-{split}-{row['query-id']}"
+        queries[query_id] = row["query"]
+
+    # Load corpus (images)
+    corpus_ds = load_dataset(dataset_path, "corpus", split=split, revision=revision)
+
+    corpus = {}
+    for row in corpus_ds:
+        corpus_id = f"corpus-{split}-{row['corpus-id']}"
+        # Extract image from the dataset row
+        if "image" in row:
+            corpus[corpus_id] = row["image"]
+        elif "page_image" in row:
+            corpus[corpus_id] = row["page_image"]
+        else:
+            raise ValueError(
+                f"No image field found in corpus. Available fields: {list(row.keys())}"
+            )
+
+    # Load qrels (relevance judgments)
+    qrels_ds = load_dataset(dataset_path, "qrels", split=split, revision=revision)
+
+    qrels = {}
+    for row in qrels_ds:
+        query_id = f"query-{split}-{row['query-id']}"
+        corpus_id = f"corpus-{split}-{row['corpus-id']}"
+        if query_id not in qrels:
+            qrels[query_id] = {}
+        qrels[query_id][corpus_id] = int(row["score"])
+
+    print(
+        f"Loaded {len(queries)} queries, {len(corpus)} corpus items, {len(qrels)} query-relevance mappings"
+    )
+
+    # Filter qrels to only include queries that exist
+    qrels = {qid: rel_docs for qid, rel_docs in qrels.items() if qid in queries}
+
+    # Filter out queries without any relevant documents (matching MTEB behavior)
+    # This is important for correct NDCG calculation
+    qrels_filtered = {qid: rel_docs for qid, rel_docs in qrels.items() if len(rel_docs) > 0}
+    queries_filtered = {
+        qid: query_text for qid, query_text in queries.items() if qid in qrels_filtered
+    }
+
+    print(
+        f"After filtering queries without positives: {len(queries_filtered)} queries, {len(qrels_filtered)} query-relevance mappings"
+    )
+
+    return corpus, queries_filtered, qrels_filtered
+
+
+def evaluate_task(
+    task_name: str,
+    model_name: str,
+    index_path: str,
+    use_fast_plaid: bool = False,
+    fast_plaid_index_path: Optional[str] = None,
+    language: Optional[str] = None,
+    rebuild_index: bool = False,
+    top_k: int = 100,
+    first_stage_k: int = 500,
+    k_values: Optional[list[int]] = None,
+    output_dir: Optional[str] = None,
+):
+    """
+    Evaluate a single ViDoRe v2 task.
+    """
+    print(f"\n{'=' * 80}")
+    print(f"Evaluating task: {task_name}")
+    print(f"{'=' * 80}")
+
+    # Get task config
+    if task_name not in VIDORE_V2_TASKS:
+        raise ValueError(f"Unknown task: {task_name}. Available: {list(VIDORE_V2_TASKS.keys())}")
+
+    task_config = VIDORE_V2_TASKS[task_name]
+    dataset_path = task_config["dataset_path"]
+    revision = task_config["revision"]
+
+    # Determine language
+    if language is None:
+        # Use first language if multiple available
+        languages = task_config.get("languages")
+        if languages is None:
+            # Task doesn't support language filtering (e.g., Vidore2ESGReportsHLRetrieval)
+            language = None
+        elif len(languages) == 1:
+            language = languages[0]
+        else:
+            language = None
+
+    # Initialize k_values if not provided
+    if k_values is None:
+        k_values = [1, 3, 5, 10, 100]
+
+    # Load data
+    corpus, queries, qrels = load_vidore_v2_data(
+        dataset_path=dataset_path,
+        revision=revision,
+        split="test",
+        language=language,
+    )
+
+    # Check if we have any queries
+    if len(queries) == 0:
+        print(
+            f"\nWarning: No queries found for task {task_name} with language {language}. Skipping evaluation."
+        )
+        # Return zero scores
+        scores = {}
+        for k in k_values:
+            scores[f"ndcg_at_{k}"] = 0.0
+            scores[f"map_at_{k}"] = 0.0
+            scores[f"recall_at_{k}"] = 0.0
+            scores[f"precision_at_{k}"] = 0.0
+            scores[f"mrr_at_{k}"] = 0.0
+        return scores
+
+    # Initialize evaluator
+    evaluator = ViDoReBenchmarkEvaluator(
+        model_name=model_name,
+        use_fast_plaid=use_fast_plaid,
+        top_k=top_k,
+        first_stage_k=first_stage_k,
+        k_values=k_values,
+    )
+
+    # Build or load index
+    index_path_full = index_path if not use_fast_plaid else fast_plaid_index_path
+    if index_path_full is None:
+        index_path_full = f"./indexes/{task_name}_{model_name}"
+        if use_fast_plaid:
+            index_path_full = f"./indexes/{task_name}_{model_name}_fastplaid"
+
+    index_or_retriever, corpus_ids_ordered = evaluator.build_index_from_corpus(
+        corpus=corpus,
+        index_path=index_path_full,
+        rebuild=rebuild_index,
+    )
+
+    # Search queries
+    task_prompt = task_config.get("prompt")
+    results = evaluator.search_queries(
+        queries=queries,
+        corpus_ids=corpus_ids_ordered,
+        index_or_retriever=index_or_retriever,
+        fast_plaid_index_path=fast_plaid_index_path,
+        task_prompt=task_prompt,
+    )
+
+    # Evaluate
+    scores = evaluator.evaluate_results(results, qrels, k_values=k_values)
+
+    # Print results
+    print(f"\n{'=' * 80}")
+    print(f"Results for {task_name}:")
+    print(f"{'=' * 80}")
+    for metric, value in scores.items():
+        if isinstance(value, (int, float)):
+            print(f"  {metric}: {value:.5f}")
+
+    # Save results
+    if output_dir:
+        os.makedirs(output_dir, exist_ok=True)
+        results_file = os.path.join(output_dir, f"{task_name}_results.json")
+        scores_file = os.path.join(output_dir, f"{task_name}_scores.json")
+
+        with open(results_file, "w") as f:
+            json.dump(results, f, indent=2)
+        print(f"\nSaved results to: {results_file}")
+
+        with open(scores_file, "w") as f:
+            json.dump(scores, f, indent=2)
+        print(f"Saved scores to: {scores_file}")
+
+    return scores
+
+
+def main():
+    parser = argparse.ArgumentParser(
+        description="Evaluate ViDoRe v2 benchmark using LEANN/Fast-Plaid indexing"
+    )
+    parser.add_argument(
+        "--model",
+        type=str,
+        default="colqwen2",
+        choices=["colqwen2", "colpali"],
+        help="Model to use",
+    )
+    parser.add_argument(
+        "--task",
+        type=str,
+        default=None,
+        help="Specific task to evaluate (or 'all' for all tasks)",
+    )
+    parser.add_argument(
+        "--tasks",
+        type=str,
+        default="all",
+        help="Tasks to evaluate: 'all' or comma-separated list",
+    )
+    parser.add_argument(
+        "--index-path",
+        type=str,
+        default=None,
+        help="Path to LEANN index (auto-generated if not provided)",
+    )
+    parser.add_argument(
+        "--use-fast-plaid",
+        action="store_true",
+        help="Use Fast-Plaid instead of LEANN",
+    )
+    parser.add_argument(
+        "--fast-plaid-index-path",
+        type=str,
+        default=None,
+        help="Path to Fast-Plaid index (auto-generated if not provided)",
+    )
+    parser.add_argument(
+        "--rebuild-index",
+        action="store_true",
+        help="Rebuild index even if it exists",
+    )
+    parser.add_argument(
+        "--language",
+        type=str,
+        default=None,
+        help="Language to evaluate (default: first available)",
+    )
+    parser.add_argument(
+        "--top-k",
+        type=int,
+        default=100,
+        help="Top-k results to retrieve",
+    )
+    parser.add_argument(
+        "--first-stage-k",
+        type=int,
+        default=500,
+        help="First stage k for LEANN search",
+    )
+    parser.add_argument(
+        "--k-values",
+        type=str,
+        default="1,3,5,10,100",
+        help="Comma-separated k values for evaluation (e.g., '1,3,5,10,100')",
+    )
+    parser.add_argument(
+        "--output-dir",
+        type=str,
+        default="./vidore_v2_results",
+        help="Output directory for results",
+    )
+
+    args = parser.parse_args()
+
+    # Parse k_values
+    k_values = [int(k.strip()) for k in args.k_values.split(",")]
+
+    # Determine tasks to evaluate
+    if args.task:
+        tasks_to_eval = [args.task]
+    elif args.tasks.lower() == "all":
+        tasks_to_eval = list(VIDORE_V2_TASKS.keys())
+    else:
+        tasks_to_eval = [t.strip() for t in args.tasks.split(",")]
+
+    print(f"Tasks to evaluate: {tasks_to_eval}")
+
+    # Evaluate each task
+    all_scores = {}
+    for task_name in tasks_to_eval:
+        try:
+            scores = evaluate_task(
+                task_name=task_name,
+                model_name=args.model,
+                index_path=args.index_path,
+                use_fast_plaid=args.use_fast_plaid,
+                fast_plaid_index_path=args.fast_plaid_index_path,
+                language=args.language,
+                rebuild_index=args.rebuild_index,
+                top_k=args.top_k,
+                first_stage_k=args.first_stage_k,
+                k_values=k_values,
+                output_dir=args.output_dir,
+            )
+            all_scores[task_name] = scores
+        except Exception as e:
+            print(f"\nError evaluating {task_name}: {e}")
+            import traceback
+
+            traceback.print_exc()
+            continue
+
+    # Print summary
+    if all_scores:
+        print(f"\n{'=' * 80}")
+        print("SUMMARY")
+        print(f"{'=' * 80}")
+        for task_name, scores in all_scores.items():
+            print(f"\n{task_name}:")
+            # Print main metrics
+            for metric in ["ndcg_at_5", "ndcg_at_10", "ndcg_at_100", "map_at_10", "recall_at_10"]:
+                if metric in scores:
+                    print(f"  {metric}: {scores[metric]:.5f}")
+
+
+if __name__ == "__main__":
+    main()

apps/slack_data/slack_mcp_reader.py

@@ -7,6 +7,7 @@ for indexing in LEANN. It supports various Slack MCP server implementations and
 flexible message processing options.
 """
 
+import ast
 import asyncio
 import json
 import logging
@@ -146,16 +147,16 @@ class SlackMCPReader:
                     match = re.search(r"'error':\s*(\{[^}]+\})", str(e))
                     if match:
                         try:
-                            error_dict = eval(match.group(1))
-                        except (ValueError, SyntaxError, NameError):
+                            error_dict = ast.literal_eval(match.group(1))
+                        except (ValueError, SyntaxError):
                             pass
                     else:
                         # Try alternative format
                         match = re.search(r"Failed to fetch messages:\s*(\{[^}]+\})", str(e))
                         if match:
                             try:
-                                error_dict = eval(match.group(1))
-                            except (ValueError, SyntaxError, NameError):
+                                error_dict = ast.literal_eval(match.group(1))
+                            except (ValueError, SyntaxError):
                                 pass
 
                 if self._is_cache_sync_error(error_dict):

benchmarks/issue_159.py

@@ -1,98 +0,0 @@
-#!/usr/bin/env python3
-"""
-Test script to reproduce issue #159: Slow search performance
-Configuration:
-- GPU: A10
-- embedding_model: BAAI/bge-large-zh-v1.5
-- data size: 180M text (~90K chunks)
-- backend: hnsw
-"""
-
-import os
-import time
-from pathlib import Path
-
-from leann.api import LeannBuilder, LeannSearcher
-
-os.environ["LEANN_LOG_LEVEL"] = "DEBUG"
-
-# Configuration matching the issue
-INDEX_PATH = "./test_issue_159.leann"
-EMBEDDING_MODEL = "BAAI/bge-large-zh-v1.5"
-BACKEND_NAME = "hnsw"
-
-
-def generate_test_data(num_chunks=90000, chunk_size=2000):
-    """Generate test data similar to 180MB text (~90K chunks)"""
-    # Each chunk is approximately 2000 characters
-    # 90K chunks * 2000 chars ≈ 180MB
-    chunks = []
-    base_text = (
-        "这是一个测试文档。LEANN是一个创新的向量数据库, 通过图基选择性重计算实现97%的存储节省。"
-    )
-
-    for i in range(num_chunks):
-        chunk = f"{base_text} 文档编号: {i}. " * (chunk_size // len(base_text) + 1)
-        chunks.append(chunk[:chunk_size])
-
-    return chunks
-
-
-def test_search_performance():
-    """Test search performance with different configurations"""
-    print("=" * 80)
-    print("Testing LEANN Search Performance (Issue #159)")
-    print("=" * 80)
-
-    meta_path = Path(f"{INDEX_PATH}.meta.json")
-    if meta_path.exists():
-        print(f"\n✓ Index already exists at {INDEX_PATH}")
-        print("  Skipping build phase. Delete the index to rebuild.")
-    else:
-        print("\n📦 Building index...")
-        print(f"  Backend: {BACKEND_NAME}")
-        print(f"  Embedding Model: {EMBEDDING_MODEL}")
-        print("  Generating test data (~90K chunks, ~180MB)...")
-
-        chunks = generate_test_data(num_chunks=90000)
-        print(f"  Generated {len(chunks)} chunks")
-        print(f"  Total text size: {sum(len(c) for c in chunks) / (1024 * 1024):.2f} MB")
-
-        builder = LeannBuilder(
-            backend_name=BACKEND_NAME,
-            embedding_model=EMBEDDING_MODEL,
-        )
-
-        print("  Adding chunks to builder...")
-        start_time = time.time()
-        for i, chunk in enumerate(chunks):
-            builder.add_text(chunk)
-            if (i + 1) % 10000 == 0:
-                print(f"    Added {i + 1}/{len(chunks)} chunks...")
-
-        print("  Building index...")
-        build_start = time.time()
-        builder.build_index(INDEX_PATH)
-        build_time = time.time() - build_start
-        print(f"  ✓ Index built in {build_time:.2f} seconds")
-
-    # Test search with different complexity values
-    print("\n🔍 Testing search performance...")
-    searcher = LeannSearcher(INDEX_PATH)
-
-    test_query = "LEANN向量数据库存储优化"
-
-    # Test with minimal complexity (8)
-    print("\n  Test 4: Minimal complexity (8)")
-    print(f"    Query: '{test_query}'")
-    start_time = time.time()
-    results = searcher.search(test_query, top_k=10, complexity=8)
-    search_time = time.time() - start_time
-    print(f"    ✓ Search completed in {search_time:.2f} seconds")
-    print(f"    Results: {len(results)} items")
-
-    print("\n" + "=" * 80)
-
-
-if __name__ == "__main__":
-    test_search_performance()

docs/configuration-guide.md

@@ -158,6 +158,95 @@ builder.build_index("./indexes/my-notes", chunks)
 
 `embedding_options` is persisted to the index `meta.json`, so subsequent `LeannSearcher` or `LeannChat` sessions automatically reuse the same provider settings (the embedding server manager forwards them to the provider for you).
 
+## Optional Embedding Features
+
+### Task-Specific Prompt Templates
+
+Some embedding models are trained with task-specific prompts to differentiate between documents and queries. The most notable example is **Google's EmbeddingGemma**, which requires different prompts depending on the use case:
+
+- **Indexing documents**: `"title: none | text: "`
+- **Search queries**: `"task: search result | query: "`
+
+LEANN supports automatic prompt prepending via the `--embedding-prompt-template` flag:
+
+```bash
+# Build index with EmbeddingGemma (via LM Studio or Ollama)
+leann build my-docs \
+  --docs ./documents \
+  --embedding-mode openai \
+  --embedding-model text-embedding-embeddinggemma-300m-qat \
+  --embedding-api-base http://localhost:1234/v1 \
+  --embedding-prompt-template "title: none | text: " \
+  --force
+
+# Search with query-specific prompt
+leann search my-docs \
+  --query "What is quantum computing?" \
+  --embedding-prompt-template "task: search result | query: "
+```
+
+**Important Notes:**
+- **Only use with compatible models**: EmbeddingGemma and similar task-specific models
+- **NOT for regular models**: Adding prompts to models like `nomic-embed-text`, `text-embedding-3-small`, or `bge-base-en-v1.5` will corrupt embeddings
+- **Template is saved**: Build-time templates are saved to `.meta.json` for reference
+- **Flexible prompts**: You can use any prompt string, or leave it empty (`""`)
+
+**Python API:**
+```python
+from leann.api import LeannBuilder
+
+builder = LeannBuilder(
+    embedding_mode="openai",
+    embedding_model="text-embedding-embeddinggemma-300m-qat",
+    embedding_options={
+        "base_url": "http://localhost:1234/v1",
+        "api_key": "lm-studio",
+        "prompt_template": "title: none | text: ",
+    },
+)
+builder.build_index("./indexes/my-docs", chunks)
+```
+
+**References:**
+- [HuggingFace Blog: EmbeddingGemma](https://huggingface.co/blog/embeddinggemma) - Technical details
+
+### LM Studio Auto-Detection (Optional)
+
+When using LM Studio with the OpenAI-compatible API, LEANN can optionally auto-detect model context lengths via the LM Studio SDK. This eliminates manual configuration for token limits.
+
+**Prerequisites:**
+```bash
+# Install Node.js (if not already installed)
+# Then install the LM Studio SDK globally
+npm install -g @lmstudio/sdk
+```
+
+**How it works:**
+1. LEANN detects LM Studio URLs (`:1234`, `lmstudio` in URL)
+2. Queries model metadata via Node.js subprocess
+3. Automatically unloads model after query (respects your JIT auto-evict settings)
+4. Falls back to static registry if SDK unavailable
+
+**No configuration needed** - it works automatically when SDK is installed:
+
+```bash
+leann build my-docs \
+  --docs ./documents \
+  --embedding-mode openai \
+  --embedding-model text-embedding-nomic-embed-text-v1.5 \
+  --embedding-api-base http://localhost:1234/v1
+  # Context length auto-detected if SDK available
+  # Falls back to registry (2048) if not
+```
+
+**Benefits:**
+- ✅ Automatic token limit detection
+- ✅ Respects LM Studio JIT auto-evict settings
+- ✅ No manual registry maintenance
+- ✅ Graceful fallback if SDK unavailable
+
+**Note:** This is completely optional. LEANN works perfectly fine without the SDK using the built-in token limit registry.
+
 ## Index Selection: Matching Your Scale
 
 ### HNSW (Hierarchical Navigable Small World)

docs/faq.md

@@ -8,3 +8,51 @@ You can speed up the process by using a lightweight embedding model. Add this to
 --embedding-model sentence-transformers/all-MiniLM-L6-v2
 ```
 **Model sizes:** `all-MiniLM-L6-v2` (30M parameters), `facebook/contriever` (~100M parameters), `Qwen3-0.6B` (600M parameters)
+
+## 2. When should I use prompt templates?
+
+**Use prompt templates ONLY with task-specific embedding models** like Google's EmbeddingGemma. These models are specially trained to use different prompts for documents vs queries.
+
+**DO NOT use with regular models** like `nomic-embed-text`, `text-embedding-3-small`, or `bge-base-en-v1.5` - adding prompts to these models will corrupt the embeddings.
+
+**Example usage with EmbeddingGemma:**
+```bash
+# Build with document prompt
+leann build my-docs --embedding-prompt-template "title: none | text: "
+
+# Search with query prompt
+leann search my-docs --query "your question" --embedding-prompt-template "task: search result | query: "
+```
+
+See the [Configuration Guide: Task-Specific Prompt Templates](configuration-guide.md#task-specific-prompt-templates) for detailed usage.
+
+## 3. Why is LM Studio loading multiple copies of my model?
+
+This was fixed in recent versions. LEANN now properly unloads models after querying metadata, respecting your LM Studio JIT auto-evict settings.
+
+**If you still see duplicates:**
+- Update to the latest LEANN version
+- Restart LM Studio to clear loaded models
+- Check that you have JIT auto-evict enabled in LM Studio settings
+
+**How it works now:**
+1. LEANN loads model temporarily to get context length
+2. Immediately unloads after query
+3. LM Studio JIT loads model on-demand for actual embeddings
+4. Auto-evicts per your settings
+
+## 4. Do I need Node.js and @lmstudio/sdk?
+
+**No, it's completely optional.** LEANN works perfectly fine without them using a built-in token limit registry.
+
+**Benefits if you install it:**
+- Automatic context length detection for LM Studio models
+- No manual registry maintenance
+- Always gets accurate token limits from the model itself
+
+**To install (optional):**
+```bash
+npm install -g @lmstudio/sdk
+```
+
+See [Configuration Guide: LM Studio Auto-Detection](configuration-guide.md#lm-studio-auto-detection-optional) for details.

packages/leann-backend-diskann/pyproject.toml

@@ -4,8 +4,8 @@ build-backend = "scikit_build_core.build"
 
 [project]
 name = "leann-backend-diskann"
-version = "0.3.4"
-dependencies = ["leann-core==0.3.4", "numpy", "protobuf>=3.19.0"]
+version = "0.3.5"
+dependencies = ["leann-core==0.3.5", "numpy", "protobuf>=3.19.0"]
 
 [tool.scikit-build]
 # Key: simplified CMake path

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

@@ -143,6 +143,8 @@ def create_hnsw_embedding_server(
             pass
         return str(nid)
 
+    # (legacy ZMQ thread removed; using shutdown-capable server only)
+
     def zmq_server_thread_with_shutdown(shutdown_event):
         """ZMQ server thread that respects shutdown signal.
 
@@ -156,238 +158,225 @@ def create_hnsw_embedding_server(
         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)
 
-        last_request_type = "unknown"
+        # Track last request type/length for shape-correct fallbacks
+        last_request_type = "unknown"  # 'text' | 'distance' | 'embedding' | 'unknown'
         last_request_length = 0
 
-        def _build_safe_fallback():
-            if last_request_type == "distance":
-                large_distance = 1e9
-                fallback_len = max(0, int(last_request_length))
-                return [[large_distance] * fallback_len]
-            if last_request_type == "embedding":
-                bsz = max(0, int(last_request_length))
-                dim = max(0, int(embedding_dim))
-                if dim > 0:
-                    return [[bsz, dim], [0.0] * (bsz * dim)]
-                return [[0, 0], []]
-            if last_request_type == "text":
-                return []
-            return [[0, int(embedding_dim) if embedding_dim > 0 else 0], []]
-
-        def _handle_text_embedding(request: list[str]) -> None:
-            nonlocal last_request_type, last_request_length
-
-            e2e_start = time.time()
-            last_request_type = "text"
-            last_request_length = len(request)
-            embeddings = compute_embeddings(
-                request,
-                model_name,
-                mode=embedding_mode,
-                provider_options=PROVIDER_OPTIONS,
-            )
-            rep_socket.send(msgpack.packb(embeddings.tolist()))
-            e2e_end = time.time()
-            logger.info(f"⏱️  Direct text embedding E2E time: {e2e_end - e2e_start:.6f}s")
-
-        def _handle_distance_request(request: list[Any]) -> None:
-            nonlocal last_request_type, last_request_length
-
-            e2e_start = time.time()
-            node_ids = request[0]
-            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)}")
-
-            texts: list[str] = []
-            found_indices: list[int] = []
-            for idx, nid in enumerate(node_ids):
-                try:
-                    passage_id = _map_node_id(nid)
-                    passage_data = passages.get_passage(passage_id)
-                    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 {passage_id}")
-                except KeyError:
-                    logger.error(f"Passage ID {nid} not found")
-                except Exception as exc:
-                    logger.error(f"Exception looking up passage ID {nid}: {exc}")
-
-            large_distance = 1e9
-            response_distances = [large_distance] * len(node_ids)
-
-            if texts:
-                try:
-                    embeddings = compute_embeddings(
-                        texts,
-                        model_name,
-                        mode=embedding_mode,
-                        provider_options=PROVIDER_OPTIONS,
-                    )
-                    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:
-                        partial = -np.dot(embeddings, query_vector)
-
-                    for pos, dval in zip(found_indices, partial.flatten().tolist()):
-                        response_distances[pos] = float(dval)
-                except Exception as exc:
-                    logger.error(f"Distance computation error, using sentinels: {exc}")
-
-            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")
-
-        def _handle_embedding_by_id(request: Any) -> None:
-            nonlocal last_request_type, last_request_length
-
-            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 = []
-
-            e2e_start = time.time()
-            last_request_type = "embedding"
-            last_request_length = len(node_ids)
-            logger.info(f"ZMQ received {len(node_ids)} node IDs for embedding fetch")
-
-            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])
-
-            texts: list[str] = []
-            found_indices: list[int] = []
-            for idx, nid in enumerate(node_ids):
-                try:
-                    passage_id = _map_node_id(nid)
-                    passage_data = passages.get_passage(passage_id)
-                    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 {passage_id}")
-                except KeyError:
-                    logger.error(f"Passage with ID {nid} not found")
-                except Exception as exc:
-                    logger.error(f"Exception looking up passage ID {nid}: {exc}")
-
-            if texts:
-                try:
-                    embeddings = compute_embeddings(
-                        texts,
-                        model_name,
-                        mode=embedding_mode,
-                        provider_options=PROVIDER_OPTIONS,
-                    )
-                    logger.info(
-                        f"Computed embeddings for {len(texts)} texts, shape: {embeddings.shape}"
-                    )
-
-                    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 exc:
-                    logger.error(f"Embedding computation error, returning zeros: {exc}")
-
-            response_payload = [dims, flat_data]
-            rep_socket.send(msgpack.packb(response_payload, use_single_float=True))
-            e2e_end = time.time()
-            logger.info(f"⏱️ Fallback Embed by Id E2E time: {e2e_end - e2e_start:.6f}s")
-
         try:
             while not shutdown_event.is_set():
                 try:
+                    e2e_start = time.time()
                     logger.debug("🔍 Waiting for ZMQ message...")
                     request_bytes = rep_socket.recv()
-                except zmq.Again:
-                    continue
 
-                try:
+                    # Rest of the processing logic (same as original)
                     request = msgpack.unpackb(request_bytes)
-                except Exception as exc:
-                    if shutdown_event.is_set():
-                        logger.info("Shutdown in progress, ignoring ZMQ error")
-                        break
-                    logger.error(f"Error unpacking ZMQ message: {exc}")
-                    try:
-                        safe = _build_safe_fallback()
-                        rep_socket.send(msgpack.packb(safe, use_single_float=True))
-                    except Exception:
-                        pass
-                    continue
 
-                try:
-                    # Model query
+                    if len(request) == 1 and request[0] == "__QUERY_MODEL__":
+                        response_bytes = msgpack.packb([model_name])
+                        rep_socket.send(response_bytes)
+                        continue
+
+                    # Handle direct text embedding request
                     if (
-                        isinstance(request, list)
-                        and len(request) == 1
-                        and request[0] == "__QUERY_MODEL__"
-                    ):
-                        rep_socket.send(msgpack.packb([model_name]))
-                    # Direct text embedding
-                    elif (
                         isinstance(request, list)
                         and request
                         and all(isinstance(item, str) for item in request)
                     ):
-                        _handle_text_embedding(request)
-                    # Distance calculation: [[ids], [query_vector]]
-                    elif (
+                        last_request_type = "text"
+                        last_request_length = len(request)
+                        embeddings = compute_embeddings(
+                            request,
+                            model_name,
+                            mode=embedding_mode,
+                            provider_options=PROVIDER_OPTIONS,
+                        )
+                        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 request: [[ids], [query_vector]]
+                    if (
                         isinstance(request, list)
                         and len(request) == 2
                         and isinstance(request[0], list)
                         and isinstance(request[1], list)
                     ):
-                        _handle_distance_request(request)
-                    # Embedding-by-id fallback
+                        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)}")
+
+                        # Gather texts for found ids
+                        texts: list[str] = []
+                        found_indices: list[int] = []
+                        for idx, nid in enumerate(node_ids):
+                            try:
+                                passage_id = _map_node_id(nid)
+                                passage_data = passages.get_passage(passage_id)
+                                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 {passage_id}")
+                            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,
+                                    provider_options=PROVIDER_OPTIONS,
+                                )
+                                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_id = _map_node_id(nid)
+                            passage_data = passages.get_passage(passage_id)
+                            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 {passage_id}")
+                        except KeyError:
+                            logger.error(f"Passage with ID {nid} not found")
+                        except Exception as e:
+                            logger.error(f"Exception looking up passage ID {nid}: {e}")
+
+                    if texts:
+                        try:
+                            embeddings = compute_embeddings(
+                                texts,
+                                model_name,
+                                mode=embedding_mode,
+                                provider_options=PROVIDER_OPTIONS,
+                            )
+                            logger.info(
+                                f"Computed embeddings for {len(texts)} texts, shape: {embeddings.shape}"
+                            )
+
+                            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 = [dims, flat_data]
+                    response_bytes = msgpack.packb(response_payload, use_single_float=True)
+
+                    rep_socket.send(response_bytes)
+                    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}")
+                        # 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:
-                        _handle_embedding_by_id(request)
-                except Exception as exc:
-                    if shutdown_event.is_set():
                         logger.info("Shutdown in progress, ignoring ZMQ error")
                         break
-                    logger.error(f"Error in ZMQ server loop: {exc}")
-                    try:
-                        safe = _build_safe_fallback()
-                        rep_socket.send(msgpack.packb(safe, use_single_float=True))
-                    except Exception:
-                        pass
         finally:
             try:
                 rep_socket.close(0)

packages/leann-backend-hnsw/pyproject.toml

@@ -6,10 +6,10 @@ build-backend = "scikit_build_core.build"
 
 [project]
 name = "leann-backend-hnsw"
-version = "0.3.4"
+version = "0.3.5"
 description = "Custom-built HNSW (Faiss) backend for the Leann toolkit."
 dependencies = [
-    "leann-core==0.3.4",
+    "leann-core==0.3.5",
     "numpy",
     "pyzmq>=23.0.0",
     "msgpack>=1.0.0",

packages/leann-core/pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "leann-core"
-version = "0.3.4"
+version = "0.3.5"
 description = "Core API and plugin system for LEANN"
 readme = "README.md"
 requires-python = ">=3.9"

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

@@ -864,13 +864,7 @@ class LeannBuilder:
 
 
 class LeannSearcher:
-    def __init__(
-        self,
-        index_path: str,
-        enable_warmup: bool = True,
-        recompute_embeddings: bool = True,
-        **backend_kwargs,
-    ):
+    def __init__(self, index_path: str, enable_warmup: bool = False, **backend_kwargs):
         # Fix path resolution for Colab and other environments
         if not Path(index_path).is_absolute():
             index_path = str(Path(index_path).resolve())
@@ -901,32 +895,14 @@ class LeannSearcher:
         backend_factory = BACKEND_REGISTRY.get(backend_name)
         if backend_factory is None:
             raise ValueError(f"Backend '{backend_name}' not found.")
-
-        # Global recompute flag for this searcher (explicit knob, default True)
-        self.recompute_embeddings: bool = bool(recompute_embeddings)
-
-        # Warmup flag: keep using the existing enable_warmup parameter,
-        # but default it to True so cold-start happens earlier.
-        self._warmup: bool = bool(enable_warmup)
-
         final_kwargs = {**self.meta_data.get("backend_kwargs", {}), **backend_kwargs}
-        final_kwargs["enable_warmup"] = self._warmup
+        final_kwargs["enable_warmup"] = enable_warmup
         if self.embedding_options:
             final_kwargs.setdefault("embedding_options", self.embedding_options)
         self.backend_impl: LeannBackendSearcherInterface = backend_factory.searcher(
             index_path, **final_kwargs
         )
 
-        # Optional one-shot warmup at construction time to hide cold-start latency.
-        if self._warmup:
-            try:
-                _ = self.backend_impl.compute_query_embedding(
-                    "__LEANN_WARMUP__",
-                    use_server_if_available=self.recompute_embeddings,
-                )
-            except Exception as exc:
-                logger.warning(f"Warmup embedding failed (ignored): {exc}")
-
     def search(
         self,
         query: str,
@@ -934,12 +910,13 @@ class LeannSearcher:
         complexity: int = 64,
         beam_width: int = 1,
         prune_ratio: float = 0.0,
-        recompute_embeddings: Optional[bool] = None,
+        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,
+        provider_options: Optional[dict[str, Any]] = None,
         **kwargs,
     ) -> list[SearchResult]:
         """
@@ -951,8 +928,7 @@ class LeannSearcher:
             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: (Deprecated) Per-call override for recompute mode.
-                Configure this at LeannSearcher(..., recompute_embeddings=...) instead.
+            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.
@@ -991,19 +967,8 @@ class LeannSearcher:
 
         zmq_port = None
 
-        # Resolve effective recompute flag for this search.
-        if recompute_embeddings is not None:
-            logger.warning(
-                "LeannSearcher.search(..., recompute_embeddings=...) is deprecated and "
-                "will be removed in a future version. Configure recompute at "
-                "LeannSearcher(..., recompute_embeddings=...) instead."
-            )
-            effective_recompute = bool(recompute_embeddings)
-        else:
-            effective_recompute = self.recompute_embeddings
-
         start_time = time.time()
-        if effective_recompute:
+        if recompute_embeddings:
             zmq_port = self.backend_impl._ensure_server_running(
                 self.meta_path_str,
                 port=expected_zmq_port,
@@ -1015,10 +980,24 @@ class LeannSearcher:
 
         start_time = time.time()
 
+        # Extract query template from stored embedding_options with fallback chain:
+        # 1. Check provider_options override (highest priority)
+        # 2. Check query_prompt_template (new format)
+        # 3. Check prompt_template (old format for backward compat)
+        # 4. None (no template)
+        query_template = None
+        if provider_options and "prompt_template" in provider_options:
+            query_template = provider_options["prompt_template"]
+        elif "query_prompt_template" in self.embedding_options:
+            query_template = self.embedding_options["query_prompt_template"]
+        elif "prompt_template" in self.embedding_options:
+            query_template = self.embedding_options["prompt_template"]
+
         query_embedding = self.backend_impl.compute_query_embedding(
             query,
-            use_server_if_available=effective_recompute,
+            use_server_if_available=recompute_embeddings,
             zmq_port=zmq_port,
+            query_template=query_template,
         )
         logger.info(f"  Generated embedding shape: {query_embedding.shape}")
         embedding_time = time.time() - start_time
@@ -1029,7 +1008,7 @@ class LeannSearcher:
             "complexity": complexity,
             "beam_width": beam_width,
             "prune_ratio": prune_ratio,
-            "recompute_embeddings": effective_recompute,
+            "recompute_embeddings": recompute_embeddings,
             "pruning_strategy": pruning_strategy,
             "zmq_port": zmq_port,
         }

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

@@ -144,6 +144,18 @@ Examples:
             default=None,
             help="API key for embedding service (defaults to OPENAI_API_KEY)",
         )
+        build_parser.add_argument(
+            "--embedding-prompt-template",
+            type=str,
+            default=None,
+            help="Prompt template to prepend to all texts for embedding (e.g., 'query: ' for search)",
+        )
+        build_parser.add_argument(
+            "--query-prompt-template",
+            type=str,
+            default=None,
+            help="Prompt template for queries (different from build template for task-specific models)",
+        )
         build_parser.add_argument(
             "--force", "-f", action="store_true", help="Force rebuild existing index"
         )
@@ -260,6 +272,12 @@ Examples:
             action="store_true",
             help="Display file paths and metadata in search results",
         )
+        search_parser.add_argument(
+            "--embedding-prompt-template",
+            type=str,
+            default=None,
+            help="Prompt template to prepend to query for embedding (e.g., 'query: ' for search)",
+        )
 
         # Ask command
         ask_parser = subparsers.add_parser("ask", help="Ask questions")
@@ -1162,6 +1180,11 @@ Examples:
                             print(f"Warning: Could not process {file_path}: {e}")
 
             # Load other file types with default reader
+            # Exclude PDFs from code_extensions if they were already processed separately
+            other_file_extensions = code_extensions
+            if should_process_pdfs and ".pdf" in code_extensions:
+                other_file_extensions = [ext for ext in code_extensions if ext != ".pdf"]
+
             try:
                 # Create a custom file filter function using our PathSpec
                 def file_filter(
@@ -1177,15 +1200,19 @@ Examples:
                     except (ValueError, OSError):
                         return True  # Include files that can't be processed
 
-                other_docs = SimpleDirectoryReader(
-                    docs_dir,
-                    recursive=True,
-                    encoding="utf-8",
-                    required_exts=code_extensions,
-                    file_extractor={},  # Use default extractors
-                    exclude_hidden=not include_hidden,
-                    filename_as_id=True,
-                ).load_data(show_progress=True)
+                # Only load other file types if there are extensions to process
+                if other_file_extensions:
+                    other_docs = SimpleDirectoryReader(
+                        docs_dir,
+                        recursive=True,
+                        encoding="utf-8",
+                        required_exts=other_file_extensions,
+                        file_extractor={},  # Use default extractors
+                        exclude_hidden=not include_hidden,
+                        filename_as_id=True,
+                    ).load_data(show_progress=True)
+                else:
+                    other_docs = []
 
                 # Filter documents after loading based on gitignore rules
                 filtered_docs = []
@@ -1398,6 +1425,14 @@ Examples:
             resolved_embedding_key = resolve_openai_api_key(args.embedding_api_key)
             if resolved_embedding_key:
                 embedding_options["api_key"] = resolved_embedding_key
+        if args.query_prompt_template:
+            # New format: separate templates
+            if args.embedding_prompt_template:
+                embedding_options["build_prompt_template"] = args.embedding_prompt_template
+            embedding_options["query_prompt_template"] = args.query_prompt_template
+        elif args.embedding_prompt_template:
+            # Old format: single template (backward compat)
+            embedding_options["prompt_template"] = args.embedding_prompt_template
 
         builder = LeannBuilder(
             backend_name=args.backend_name,
@@ -1519,6 +1554,11 @@ Examples:
                         print("Invalid input. Aborting search.")
                         return
 
+        # Build provider_options for runtime override
+        provider_options = {}
+        if args.embedding_prompt_template:
+            provider_options["prompt_template"] = args.embedding_prompt_template
+
         searcher = LeannSearcher(index_path=index_path)
         results = searcher.search(
             query,
@@ -1528,6 +1568,7 @@ Examples:
             prune_ratio=args.prune_ratio,
             recompute_embeddings=args.recompute_embeddings,
             pruning_strategy=args.pruning_strategy,
+            provider_options=provider_options if provider_options else None,
         )
 
         print(f"Search results for '{query}' (top {len(results)}):")

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

@@ -4,8 +4,10 @@ Consolidates all embedding computation logic using SentenceTransformer
 Preserves all optimization parameters to ensure performance
 """
 
+import json
 import logging
 import os
+import subprocess
 import time
 from typing import Any, Optional
 
@@ -40,6 +42,11 @@ EMBEDDING_MODEL_LIMITS = {
     "text-embedding-ada-002": 8192,
 }
 
+# Runtime cache for dynamically discovered token limits
+# Key: (model_name, base_url), Value: token_limit
+# Prevents repeated SDK/API calls for the same model
+_token_limit_cache: dict[tuple[str, str], int] = {}
+
 
 def get_model_token_limit(
     model_name: str,
@@ -49,6 +56,7 @@ def get_model_token_limit(
     """
     Get token limit for a given embedding model.
     Uses hybrid approach: dynamic discovery for Ollama, registry fallback for others.
+    Caches discovered limits to prevent repeated API/SDK calls.
 
     Args:
         model_name: Name of the embedding model
@@ -58,12 +66,33 @@ def get_model_token_limit(
     Returns:
         Token limit for the model in tokens
     """
+    # Check cache first to avoid repeated SDK/API calls
+    cache_key = (model_name, base_url or "")
+    if cache_key in _token_limit_cache:
+        cached_limit = _token_limit_cache[cache_key]
+        logger.debug(f"Using cached token limit for {model_name}: {cached_limit}")
+        return cached_limit
+
     # Try Ollama dynamic discovery if base_url provided
     if base_url:
         # Detect Ollama servers by port or "ollama" in URL
         if "11434" in base_url or "ollama" in base_url.lower():
             limit = _query_ollama_context_limit(model_name, base_url)
             if limit:
+                _token_limit_cache[cache_key] = limit
+                return limit
+
+        # Try LM Studio SDK discovery
+        if "1234" in base_url or "lmstudio" in base_url.lower() or "lm.studio" in base_url.lower():
+            # Convert HTTP to WebSocket URL
+            ws_url = base_url.replace("https://", "wss://").replace("http://", "ws://")
+            # Remove /v1 suffix if present
+            if ws_url.endswith("/v1"):
+                ws_url = ws_url[:-3]
+
+            limit = _query_lmstudio_context_limit(model_name, ws_url)
+            if limit:
+                _token_limit_cache[cache_key] = limit
                 return limit
 
     # Fallback to known model registry with version handling (from PR #154)
@@ -72,19 +101,25 @@ def get_model_token_limit(
 
     # Check exact match first
     if model_name in EMBEDDING_MODEL_LIMITS:
-        return EMBEDDING_MODEL_LIMITS[model_name]
+        limit = EMBEDDING_MODEL_LIMITS[model_name]
+        _token_limit_cache[cache_key] = limit
+        return limit
 
     # Check base name match
     if base_model_name in EMBEDDING_MODEL_LIMITS:
-        return EMBEDDING_MODEL_LIMITS[base_model_name]
+        limit = EMBEDDING_MODEL_LIMITS[base_model_name]
+        _token_limit_cache[cache_key] = limit
+        return limit
 
     # Check partial matches for common patterns
-    for known_model, limit in EMBEDDING_MODEL_LIMITS.items():
+    for known_model, registry_limit in EMBEDDING_MODEL_LIMITS.items():
         if known_model in base_model_name or base_model_name in known_model:
-            return limit
+            _token_limit_cache[cache_key] = registry_limit
+            return registry_limit
 
     # Default fallback
     logger.warning(f"Unknown model '{model_name}', using default {default} token limit")
+    _token_limit_cache[cache_key] = default
     return default
 
 
@@ -185,6 +220,91 @@ def _query_ollama_context_limit(model_name: str, base_url: str) -> Optional[int]
     return None
 
 
+def _query_lmstudio_context_limit(model_name: str, base_url: str) -> Optional[int]:
+    """
+    Query LM Studio SDK for model context length via Node.js subprocess.
+
+    Args:
+        model_name: Name of the LM Studio model
+        base_url: Base URL of the LM Studio server (WebSocket format, e.g., "ws://localhost:1234")
+
+    Returns:
+        Context limit in tokens if found, None otherwise
+    """
+    # Inline JavaScript using @lmstudio/sdk
+    # Note: Load model temporarily for metadata, then unload to respect JIT auto-evict
+    js_code = f"""
+    const {{ LMStudioClient }} = require('@lmstudio/sdk');
+    (async () => {{
+        try {{
+            const client = new LMStudioClient({{ baseUrl: '{base_url}' }});
+            const model = await client.embedding.load('{model_name}', {{ verbose: false }});
+            const contextLength = await model.getContextLength();
+            await model.unload();  // Unload immediately to respect JIT auto-evict settings
+            console.log(JSON.stringify({{ contextLength, identifier: '{model_name}' }}));
+        }} catch (error) {{
+            console.error(JSON.stringify({{ error: error.message }}));
+            process.exit(1);
+        }}
+    }})();
+    """
+
+    try:
+        # Set NODE_PATH to include global modules for @lmstudio/sdk resolution
+        env = os.environ.copy()
+
+        # Try to get npm global root (works with nvm, brew node, etc.)
+        try:
+            npm_root = subprocess.run(
+                ["npm", "root", "-g"],
+                capture_output=True,
+                text=True,
+                timeout=5,
+            )
+            if npm_root.returncode == 0:
+                global_modules = npm_root.stdout.strip()
+                # Append to existing NODE_PATH if present
+                existing_node_path = env.get("NODE_PATH", "")
+                env["NODE_PATH"] = (
+                    f"{global_modules}:{existing_node_path}"
+                    if existing_node_path
+                    else global_modules
+                )
+        except Exception:
+            # If npm not available, continue with existing NODE_PATH
+            pass
+
+        result = subprocess.run(
+            ["node", "-e", js_code],
+            capture_output=True,
+            text=True,
+            timeout=10,
+            env=env,
+        )
+
+        if result.returncode != 0:
+            logger.debug(f"LM Studio SDK error: {result.stderr}")
+            return None
+
+        data = json.loads(result.stdout)
+        context_length = data.get("contextLength")
+
+        if context_length and context_length > 0:
+            logger.info(f"LM Studio SDK detected {model_name} context length: {context_length}")
+            return context_length
+
+    except FileNotFoundError:
+        logger.debug("Node.js not found - install Node.js for LM Studio SDK features")
+    except subprocess.TimeoutExpired:
+        logger.debug("LM Studio SDK query timeout")
+    except json.JSONDecodeError:
+        logger.debug("LM Studio SDK returned invalid JSON")
+    except Exception as e:
+        logger.debug(f"LM Studio SDK query failed: {e}")
+
+    return None
+
+
 # Global model cache to avoid repeated loading
 _model_cache: dict[str, Any] = {}
 
@@ -215,14 +335,9 @@ def compute_embeddings(
         Normalized embeddings array, shape: (len(texts), embedding_dim)
     """
     provider_options = provider_options or {}
-    wrapper_start_time = time.time()
-    logger.debug(
-        f"[compute_embeddings] entry: mode={mode}, model='{model_name}', text_count={len(texts)}"
-    )
 
     if mode == "sentence-transformers":
-        inner_start_time = time.time()
-        result = compute_embeddings_sentence_transformers(
+        return compute_embeddings_sentence_transformers(
             texts,
             model_name,
             is_build=is_build,
@@ -231,20 +346,13 @@ def compute_embeddings(
             manual_tokenize=manual_tokenize,
             max_length=max_length,
         )
-        inner_end_time = time.time()
-        wrapper_end_time = time.time()
-        logger.debug(
-            "[compute_embeddings] sentence-transformers timings: "
-            f"inner={inner_end_time - inner_start_time:.6f}s, "
-            f"wrapper_total={wrapper_end_time - wrapper_start_time:.6f}s"
-        )
-        return result
     elif mode == "openai":
         return compute_embeddings_openai(
             texts,
             model_name,
             base_url=provider_options.get("base_url"),
             api_key=provider_options.get("api_key"),
+            provider_options=provider_options,
         )
     elif mode == "mlx":
         return compute_embeddings_mlx(texts, model_name)
@@ -254,6 +362,7 @@ def compute_embeddings(
             model_name,
             is_build=is_build,
             host=provider_options.get("host"),
+            provider_options=provider_options,
         )
     elif mode == "gemini":
         return compute_embeddings_gemini(texts, model_name, is_build=is_build)
@@ -284,7 +393,6 @@ def compute_embeddings_sentence_transformers(
         is_build: Whether this is a build operation (shows progress bar)
         adaptive_optimization: Whether to use adaptive optimization based on batch size
     """
-    outer_start_time = time.time()
     # Handle empty input
     if not texts:
         raise ValueError("Cannot compute embeddings for empty text list")
@@ -315,14 +423,7 @@ def compute_embeddings_sentence_transformers(
     # Create cache key
     cache_key = f"sentence_transformers_{model_name}_{device}_{use_fp16}_optimized"
 
-    pre_model_init_end_time = time.time()
-    logger.debug(
-        "compute_embeddings_sentence_transformers pre-model-init time "
-        f"(device/batch selection etc.): {pre_model_init_end_time - outer_start_time:.6f}s"
-    )
-
     # Check if model is already cached
-    start_time = time.time()
     if cache_key in _model_cache:
         logger.info(f"Using cached optimized model: {model_name}")
         model = _model_cache[cache_key]
@@ -462,13 +563,10 @@ def compute_embeddings_sentence_transformers(
         _model_cache[cache_key] = model
         logger.info(f"Model cached: {cache_key}")
 
-        end_time = time.time()
-
-        # Compute embeddings with optimized inference mode
-        logger.info(
-            f"Starting embedding computation... (batch_size: {batch_size}, manual_tokenize={manual_tokenize})"
-        )
-        logger.info(f"start sentence transformers {model} takes {end_time - start_time}")
+    # Compute embeddings with optimized inference mode
+    logger.info(
+        f"Starting embedding computation... (batch_size: {batch_size}, manual_tokenize={manual_tokenize})"
+    )
 
     start_time = time.time()
     if not manual_tokenize:
@@ -489,46 +587,32 @@ def compute_embeddings_sentence_transformers(
         except Exception:
             pass
     else:
-        # Manual tokenization + forward pass using HF AutoTokenizer/AutoModel.
-        # This path is reserved for an aggressively optimized FP pipeline
-        # (no quantization), mainly for experimentation.
+        # 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}_fp"
-
+        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 FP path")
+            logger.info("Using cached HF tokenizer/model for manual path")
         else:
-            logger.info("Loading HF tokenizer/model for manual FP path")
+            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 = 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(  # type: ignore
-                        hf_model, mode="reduce-overhead", dynamic=True
-                    )
-                    logger.info(
-                        f"Applied torch.compile to HF model for {model_name} "
-                        f"(device={device}, dtype={torch_dtype})"
-                    )
-                except Exception as exc:
-                    logger.warning(f"torch.compile optimization failed: {exc}")
-
+                    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
 
@@ -554,6 +638,7 @@ def compute_embeddings_sentence_transformers(
             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,
@@ -561,17 +646,34 @@ def compute_embeddings_sentence_transformers(
                     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)
 
@@ -591,12 +693,6 @@ def compute_embeddings_sentence_transformers(
     if np.isnan(embeddings).any() or np.isinf(embeddings).any():
         raise RuntimeError(f"Detected NaN or Inf values in embeddings, model: {model_name}")
 
-    outer_end_time = time.time()
-    logger.debug(
-        "compute_embeddings_sentence_transformers total time "
-        f"(function entry -> return): {outer_end_time - outer_start_time:.6f}s"
-    )
-
     return embeddings
 
 
@@ -605,6 +701,7 @@ def compute_embeddings_openai(
     model_name: str,
     base_url: Optional[str] = None,
     api_key: Optional[str] = None,
+    provider_options: Optional[dict[str, Any]] = None,
 ) -> np.ndarray:
     # TODO: @yichuan-w add progress bar only in build mode
     """Compute embeddings using OpenAI API"""
@@ -623,26 +720,40 @@ def compute_embeddings_openai(
             f"Found {invalid_count} empty/invalid text(s) in input. Upstream should filter before calling OpenAI."
         )
 
-    resolved_base_url = resolve_openai_base_url(base_url)
-    resolved_api_key = resolve_openai_api_key(api_key)
+    # Extract base_url and api_key from provider_options if not provided directly
+    provider_options = provider_options or {}
+    effective_base_url = base_url or provider_options.get("base_url")
+    effective_api_key = api_key or provider_options.get("api_key")
+
+    resolved_base_url = resolve_openai_base_url(effective_base_url)
+    resolved_api_key = resolve_openai_api_key(effective_api_key)
 
     if not resolved_api_key:
         raise RuntimeError("OPENAI_API_KEY environment variable not set")
 
-    # Cache OpenAI client
-    cache_key = f"openai_client::{resolved_base_url}"
-    if cache_key in _model_cache:
-        client = _model_cache[cache_key]
-    else:
-        client = openai.OpenAI(api_key=resolved_api_key, base_url=resolved_base_url)
-        _model_cache[cache_key] = client
-        logger.info("OpenAI client cached")
+    # Create OpenAI client
+    client = openai.OpenAI(api_key=resolved_api_key, base_url=resolved_base_url)
 
     logger.info(
         f"Computing embeddings for {len(texts)} texts using OpenAI API, model: '{model_name}'"
     )
     print(f"len of texts: {len(texts)}")
 
+    # Apply prompt template if provided
+    # Priority: build_prompt_template (new format) > prompt_template (old format)
+    prompt_template = provider_options.get("build_prompt_template") or provider_options.get(
+        "prompt_template"
+    )
+
+    if prompt_template:
+        logger.warning(f"Applying prompt template: '{prompt_template}'")
+        texts = [f"{prompt_template}{text}" for text in texts]
+
+    # Query token limit and apply truncation
+    token_limit = get_model_token_limit(model_name, base_url=effective_base_url)
+    logger.info(f"Using token limit: {token_limit} for model '{model_name}'")
+    texts = truncate_to_token_limit(texts, token_limit)
+
     # OpenAI has limits on batch size and input length
     max_batch_size = 800  # Conservative batch size because the token limit is 300K
     all_embeddings = []
@@ -673,7 +784,15 @@ def compute_embeddings_openai(
         try:
             response = client.embeddings.create(model=model_name, input=batch_texts)
             batch_embeddings = [embedding.embedding for embedding in response.data]
-            all_embeddings.extend(batch_embeddings)
+
+            # Verify we got the expected number of embeddings
+            if len(batch_embeddings) != len(batch_texts):
+                logger.warning(
+                    f"Expected {len(batch_texts)} embeddings but got {len(batch_embeddings)}"
+                )
+
+            # Only take the number of embeddings that match the batch size
+            all_embeddings.extend(batch_embeddings[: len(batch_texts)])
         except Exception as e:
             logger.error(f"Batch {i} failed: {e}")
             raise
@@ -763,6 +882,7 @@ def compute_embeddings_ollama(
     model_name: str,
     is_build: bool = False,
     host: Optional[str] = None,
+    provider_options: Optional[dict[str, Any]] = None,
 ) -> np.ndarray:
     """
     Compute embeddings using Ollama API with true batch processing.
@@ -775,6 +895,7 @@ def compute_embeddings_ollama(
         model_name: Ollama model name (e.g., "nomic-embed-text", "mxbai-embed-large")
         is_build: Whether this is a build operation (shows progress bar)
         host: Ollama host URL (defaults to environment or http://localhost:11434)
+        provider_options: Optional provider-specific options (e.g., prompt_template)
 
     Returns:
         Normalized embeddings array, shape: (len(texts), embedding_dim)
@@ -911,6 +1032,17 @@ def compute_embeddings_ollama(
 
     logger.info(f"Using batch size: {batch_size} for true batch processing")
 
+    # Apply prompt template if provided
+    provider_options = provider_options or {}
+    # Priority: build_prompt_template (new format) > prompt_template (old format)
+    prompt_template = provider_options.get("build_prompt_template") or provider_options.get(
+        "prompt_template"
+    )
+
+    if prompt_template:
+        logger.warning(f"Applying prompt template: '{prompt_template}'")
+        texts = [f"{prompt_template}{text}" for text in texts]
+
     # Get model token limit and apply truncation before batching
     token_limit = get_model_token_limit(model_name, base_url=resolved_host)
     logger.info(f"Model '{model_name}' token limit: {token_limit}")

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

@@ -77,6 +77,7 @@ class LeannBackendSearcherInterface(ABC):
         query: str,
         use_server_if_available: bool = True,
         zmq_port: Optional[int] = None,
+        query_template: Optional[str] = None,
     ) -> np.ndarray:
         """Compute embedding for a query string
 
@@ -84,6 +85,7 @@ class LeannBackendSearcherInterface(ABC):
             query: The query string to embed
             zmq_port: ZMQ port for embedding server
             use_server_if_available: Whether to try using embedding server first
+            query_template: Optional prompt template to prepend to query
 
         Returns:
             Query embedding as numpy array with shape (1, D)

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

@@ -33,6 +33,8 @@ def autodiscover_backends():
     discovered_backends = []
     for dist in importlib.metadata.distributions():
         dist_name = dist.metadata["name"]
+        if dist_name is None:
+            continue
         if dist_name.startswith("leann-backend-"):
             backend_module_name = dist_name.replace("-", "_")
             discovered_backends.append(backend_module_name)

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

@@ -71,6 +71,15 @@ class BaseSearcher(LeannBackendSearcherInterface, ABC):
             or "mips"
         )
 
+        # Filter out ALL prompt templates from provider_options during search
+        # Templates are applied in compute_query_embedding (line 109-110) BEFORE server call
+        # The server should never apply templates during search to avoid double-templating
+        search_provider_options = {
+            k: v
+            for k, v in self.embedding_options.items()
+            if k not in ("build_prompt_template", "query_prompt_template", "prompt_template")
+        }
+
         server_started, actual_port = self.embedding_server_manager.start_server(
             port=port,
             model_name=self.embedding_model,
@@ -78,7 +87,7 @@ class BaseSearcher(LeannBackendSearcherInterface, ABC):
             passages_file=passages_source_file,
             distance_metric=distance_metric,
             enable_warmup=kwargs.get("enable_warmup", False),
-            provider_options=self.embedding_options,
+            provider_options=search_provider_options,
         )
         if not server_started:
             raise RuntimeError(f"Failed to start embedding server on port {actual_port}")
@@ -90,6 +99,7 @@ class BaseSearcher(LeannBackendSearcherInterface, ABC):
         query: str,
         use_server_if_available: bool = True,
         zmq_port: int = 5557,
+        query_template: Optional[str] = None,
     ) -> np.ndarray:
         """
         Compute embedding for a query string.
@@ -98,10 +108,16 @@ class BaseSearcher(LeannBackendSearcherInterface, ABC):
             query: The query string to embed
             zmq_port: ZMQ port for embedding server
             use_server_if_available: Whether to try using embedding server first
+            query_template: Optional prompt template to prepend to query
 
         Returns:
             Query embedding as numpy array
         """
+        # Apply query template BEFORE any computation path
+        # This ensures template is applied consistently for both server and fallback paths
+        if query_template:
+            query = f"{query_template}{query}"
+
         # Try to use embedding server if available and requested
         if use_server_if_available:
             try:

packages/leann/pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "leann"
-version = "0.3.4"
+version = "0.3.5"
 description = "LEANN - The smallest vector index in the world. RAG Everything with LEANN!"
 readme = "README.md"
 requires-python = ">=3.9"

pyproject.toml

@@ -69,7 +69,8 @@ diskann = [
 # Add a new optional dependency group for document processing
 documents = [
     "beautifulsoup4>=4.13.0",  # For HTML parsing
-    "python-docx>=0.8.11",     # For Word documents
+    "python-docx>=0.8.11",     # For Word documents (creating/editing)
+    "docx2txt>=0.9",           # For Word documents (text extraction)
     "openpyxl>=3.1.0",         # For Excel files
     "pandas>=2.2.0",           # For data processing
 ]
@@ -164,6 +165,7 @@ python_functions = ["test_*"]
 markers = [
     "slow: marks tests as slow (deselect with '-m \"not slow\"')",
     "openai: marks tests that require OpenAI API key",
+    "integration: marks tests that require live services (Ollama, LM Studio, etc.)",
 ]
 timeout = 300  # Reduced from 600s (10min) to 300s (5min) for CI safety
 addopts = [

tests/README.md

@@ -36,6 +36,14 @@ Tests DiskANN graph partitioning functionality:
 - Includes performance comparison between DiskANN (with partition) and HNSW
 - **Note**: These tests are skipped in CI due to hardware requirements and computation time
 
+### `test_prompt_template_e2e.py`
+Integration tests for prompt template feature with live embedding services:
+- Tests prompt template prepending with EmbeddingGemma (OpenAI-compatible API via LM Studio)
+- Tests hybrid token limit discovery (Ollama dynamic detection, registry fallback, default)
+- Tests LM Studio SDK bridge for automatic context length detection (requires Node.js + @lmstudio/sdk)
+- **Note**: These tests require live services (LM Studio, Ollama) and are marked with `@pytest.mark.integration`
+- **Important**: Prompt templates are ONLY for EmbeddingGemma and similar task-specific models, NOT regular embedding models
+
 ## Running Tests
 
 ### Install test dependencies:
@@ -66,6 +74,12 @@ pytest tests/ -m "not openai"
 # Skip slow tests
 pytest tests/ -m "not slow"
 
+# Skip integration tests (that require live services)
+pytest tests/ -m "not integration"
+
+# Run only integration tests (requires LM Studio or Ollama running)
+pytest tests/test_prompt_template_e2e.py -v -s
+
 # Run DiskANN partition tests (requires local machine, not CI)
 pytest tests/test_diskann_partition.py
 ```
@@ -101,6 +115,20 @@ The `pytest.ini` file configures:
 - Custom markers for slow and OpenAI tests
 - Verbose output with short tracebacks
 
+### Integration Test Prerequisites
+
+Integration tests (`test_prompt_template_e2e.py`) require live services:
+
+**Required:**
+- LM Studio running at `http://localhost:1234` with EmbeddingGemma model loaded
+
+**Optional:**
+- Ollama running at `http://localhost:11434` for token limit detection tests
+- Node.js + @lmstudio/sdk installed (`npm install -g @lmstudio/sdk`) for SDK bridge tests
+
+Tests gracefully skip if services are unavailable.
+
 ### Known Issues
 
 - OpenAI tests are automatically skipped if no API key is provided
+- Integration tests require live embedding services and may fail due to proxy settings (set `unset ALL_PROXY all_proxy` if needed)

tests/test_cli_prompt_template.py

@@ -0,0 +1,533 @@
+"""
+Tests for CLI argument integration of --embedding-prompt-template.
+
+These tests verify that:
+1. The --embedding-prompt-template flag is properly registered on build and search commands
+2. The template value flows from CLI args to embedding_options dict
+3. The template is passed through to compute_embeddings() function
+4. Default behavior (no flag) is handled correctly
+"""
+
+from unittest.mock import Mock, patch
+
+from leann.cli import LeannCLI
+
+
+class TestCLIPromptTemplateArgument:
+    """Tests for --embedding-prompt-template on build and search commands."""
+
+    def test_commands_accept_prompt_template_argument(self):
+        """Verify that build and search parsers accept --embedding-prompt-template flag."""
+        cli = LeannCLI()
+        parser = cli.create_parser()
+        template_value = "search_query: "
+
+        # Test build command
+        build_args = parser.parse_args(
+            [
+                "build",
+                "test-index",
+                "--docs",
+                "/tmp/test-docs",
+                "--embedding-prompt-template",
+                template_value,
+            ]
+        )
+        assert build_args.command == "build"
+        assert hasattr(build_args, "embedding_prompt_template"), (
+            "build command should have embedding_prompt_template attribute"
+        )
+        assert build_args.embedding_prompt_template == template_value
+
+        # Test search command
+        search_args = parser.parse_args(
+            ["search", "test-index", "my query", "--embedding-prompt-template", template_value]
+        )
+        assert search_args.command == "search"
+        assert hasattr(search_args, "embedding_prompt_template"), (
+            "search command should have embedding_prompt_template attribute"
+        )
+        assert search_args.embedding_prompt_template == template_value
+
+    def test_commands_default_to_none(self):
+        """Verify default value is None when flag not provided (backward compatibility)."""
+        cli = LeannCLI()
+        parser = cli.create_parser()
+
+        # Test build command default
+        build_args = parser.parse_args(["build", "test-index", "--docs", "/tmp/test-docs"])
+        assert hasattr(build_args, "embedding_prompt_template"), (
+            "build command should have embedding_prompt_template attribute"
+        )
+        assert build_args.embedding_prompt_template is None, (
+            "Build default value should be None when flag not provided"
+        )
+
+        # Test search command default
+        search_args = parser.parse_args(["search", "test-index", "my query"])
+        assert hasattr(search_args, "embedding_prompt_template"), (
+            "search command should have embedding_prompt_template attribute"
+        )
+        assert search_args.embedding_prompt_template is None, (
+            "Search default value should be None when flag not provided"
+        )
+
+
+class TestBuildCommandPromptTemplateArgumentExtras:
+    """Additional build-specific tests for prompt template argument."""
+
+    def test_build_command_prompt_template_with_multiword_value(self):
+        """
+        Verify that template values with spaces are handled correctly.
+
+        Templates like "search_document: " or "Represent this sentence for searching: "
+        should be accepted as a single string argument.
+        """
+        cli = LeannCLI()
+        parser = cli.create_parser()
+
+        template = "Represent this sentence for searching: "
+        args = parser.parse_args(
+            [
+                "build",
+                "test-index",
+                "--docs",
+                "/tmp/test-docs",
+                "--embedding-prompt-template",
+                template,
+            ]
+        )
+
+        assert args.embedding_prompt_template == template
+
+
+class TestPromptTemplateStoredInEmbeddingOptions:
+    """Tests for template storage in embedding_options dict."""
+
+    @patch("leann.cli.LeannBuilder")
+    def test_prompt_template_stored_in_embedding_options_on_build(
+        self, mock_builder_class, tmp_path
+    ):
+        """
+        Verify that when --embedding-prompt-template is provided to build command,
+        the value is stored in embedding_options dict passed to LeannBuilder.
+
+        This test will fail because the CLI doesn't currently process this argument
+        and add it to embedding_options.
+        """
+        # Setup mocks
+        mock_builder = Mock()
+        mock_builder_class.return_value = mock_builder
+
+        # Create CLI and run build command
+        cli = LeannCLI()
+
+        # Mock load_documents to return a document so builder is created
+        cli.load_documents = Mock(return_value=[{"text": "test content", "metadata": {}}])
+
+        parser = cli.create_parser()
+
+        template = "search_query: "
+        args = parser.parse_args(
+            [
+                "build",
+                "test-index",
+                "--docs",
+                str(tmp_path),
+                "--embedding-prompt-template",
+                template,
+                "--force",  # Force rebuild to ensure LeannBuilder is called
+            ]
+        )
+
+        # Run the build command
+        import asyncio
+
+        asyncio.run(cli.build_index(args))
+
+        # Check that LeannBuilder was called with embedding_options containing prompt_template
+        call_kwargs = mock_builder_class.call_args.kwargs
+        assert "embedding_options" in call_kwargs, "LeannBuilder should receive embedding_options"
+
+        embedding_options = call_kwargs["embedding_options"]
+        assert embedding_options is not None, (
+            "embedding_options should not be None when template provided"
+        )
+        assert "prompt_template" in embedding_options, (
+            "embedding_options should contain 'prompt_template' key"
+        )
+        assert embedding_options["prompt_template"] == template, (
+            f"Template should be '{template}', got {embedding_options.get('prompt_template')}"
+        )
+
+    @patch("leann.cli.LeannBuilder")
+    def test_prompt_template_not_in_options_when_not_provided(self, mock_builder_class, tmp_path):
+        """
+        Verify that when --embedding-prompt-template is NOT provided,
+        embedding_options either doesn't have the key or it's None.
+
+        This ensures we don't pass empty/None values unnecessarily.
+        """
+        # Setup mocks
+        mock_builder = Mock()
+        mock_builder_class.return_value = mock_builder
+
+        cli = LeannCLI()
+
+        # Mock load_documents to return a document so builder is created
+        cli.load_documents = Mock(return_value=[{"text": "test content", "metadata": {}}])
+
+        parser = cli.create_parser()
+
+        args = parser.parse_args(
+            [
+                "build",
+                "test-index",
+                "--docs",
+                str(tmp_path),
+                "--force",  # Force rebuild to ensure LeannBuilder is called
+            ]
+        )
+
+        import asyncio
+
+        asyncio.run(cli.build_index(args))
+
+        # Check that if embedding_options is passed, it doesn't have prompt_template
+        call_kwargs = mock_builder_class.call_args.kwargs
+        if call_kwargs.get("embedding_options"):
+            embedding_options = call_kwargs["embedding_options"]
+            # Either the key shouldn't exist, or it should be None
+            assert (
+                "prompt_template" not in embedding_options
+                or embedding_options["prompt_template"] is None
+            ), "prompt_template should not be set when flag not provided"
+
+    # R1 Tests: Build-time separate template storage
+    @patch("leann.cli.LeannBuilder")
+    def test_build_stores_separate_templates(self, mock_builder_class, tmp_path):
+        """
+        R1 Test 1: Verify that when both --embedding-prompt-template and
+        --query-prompt-template are provided to build command, both values
+        are stored separately in embedding_options dict as build_prompt_template
+        and query_prompt_template.
+
+        This test will fail because:
+        1. CLI doesn't accept --query-prompt-template flag yet
+        2. CLI doesn't store templates as separate build_prompt_template and
+           query_prompt_template keys
+
+        Expected behavior after implementation:
+        - .meta.json contains: {"embedding_options": {
+            "build_prompt_template": "doc: ",
+            "query_prompt_template": "query: "
+          }}
+        """
+        # Setup mocks
+        mock_builder = Mock()
+        mock_builder_class.return_value = mock_builder
+
+        cli = LeannCLI()
+
+        # Mock load_documents to return a document so builder is created
+        cli.load_documents = Mock(return_value=[{"text": "test content", "metadata": {}}])
+
+        parser = cli.create_parser()
+
+        build_template = "doc: "
+        query_template = "query: "
+        args = parser.parse_args(
+            [
+                "build",
+                "test-index",
+                "--docs",
+                str(tmp_path),
+                "--embedding-prompt-template",
+                build_template,
+                "--query-prompt-template",
+                query_template,
+                "--force",
+            ]
+        )
+
+        # Run the build command
+        import asyncio
+
+        asyncio.run(cli.build_index(args))
+
+        # Check that LeannBuilder was called with separate template keys
+        call_kwargs = mock_builder_class.call_args.kwargs
+        assert "embedding_options" in call_kwargs, "LeannBuilder should receive embedding_options"
+
+        embedding_options = call_kwargs["embedding_options"]
+        assert embedding_options is not None, (
+            "embedding_options should not be None when templates provided"
+        )
+
+        assert "build_prompt_template" in embedding_options, (
+            "embedding_options should contain 'build_prompt_template' key"
+        )
+        assert embedding_options["build_prompt_template"] == build_template, (
+            f"build_prompt_template should be '{build_template}'"
+        )
+
+        assert "query_prompt_template" in embedding_options, (
+            "embedding_options should contain 'query_prompt_template' key"
+        )
+        assert embedding_options["query_prompt_template"] == query_template, (
+            f"query_prompt_template should be '{query_template}'"
+        )
+
+        # Old key should NOT be present when using new separate template format
+        assert "prompt_template" not in embedding_options, (
+            "Old 'prompt_template' key should not be present with separate templates"
+        )
+
+    @patch("leann.cli.LeannBuilder")
+    def test_build_backward_compat_single_template(self, mock_builder_class, tmp_path):
+        """
+        R1 Test 2: Verify backward compatibility - when only
+        --embedding-prompt-template is provided (old behavior), it should
+        still be stored as 'prompt_template' in embedding_options.
+
+        This ensures existing workflows continue to work unchanged.
+
+        This test currently passes because it matches existing behavior, but it
+        documents the requirement that this behavior must be preserved after
+        implementing the separate template feature.
+
+        Expected behavior:
+        - .meta.json contains: {"embedding_options": {"prompt_template": "prompt: "}}
+        - No build_prompt_template or query_prompt_template keys
+        """
+        # Setup mocks
+        mock_builder = Mock()
+        mock_builder_class.return_value = mock_builder
+
+        cli = LeannCLI()
+
+        # Mock load_documents to return a document so builder is created
+        cli.load_documents = Mock(return_value=[{"text": "test content", "metadata": {}}])
+
+        parser = cli.create_parser()
+
+        template = "prompt: "
+        args = parser.parse_args(
+            [
+                "build",
+                "test-index",
+                "--docs",
+                str(tmp_path),
+                "--embedding-prompt-template",
+                template,
+                "--force",
+            ]
+        )
+
+        # Run the build command
+        import asyncio
+
+        asyncio.run(cli.build_index(args))
+
+        # Check that LeannBuilder was called with old format
+        call_kwargs = mock_builder_class.call_args.kwargs
+        assert "embedding_options" in call_kwargs, "LeannBuilder should receive embedding_options"
+
+        embedding_options = call_kwargs["embedding_options"]
+        assert embedding_options is not None, (
+            "embedding_options should not be None when template provided"
+        )
+
+        assert "prompt_template" in embedding_options, (
+            "embedding_options should contain old 'prompt_template' key for backward compat"
+        )
+        assert embedding_options["prompt_template"] == template, (
+            f"prompt_template should be '{template}'"
+        )
+
+        # New keys should NOT be present in backward compat mode
+        assert "build_prompt_template" not in embedding_options, (
+            "build_prompt_template should not be present with single template flag"
+        )
+        assert "query_prompt_template" not in embedding_options, (
+            "query_prompt_template should not be present with single template flag"
+        )
+
+    @patch("leann.cli.LeannBuilder")
+    def test_build_no_templates(self, mock_builder_class, tmp_path):
+        """
+        R1 Test 3: Verify that when no template flags are provided,
+        embedding_options has no prompt template keys.
+
+        This ensures clean defaults and no unnecessary keys in .meta.json.
+
+        This test currently passes because it matches existing behavior, but it
+        documents the requirement that this behavior must be preserved after
+        implementing the separate template feature.
+
+        Expected behavior:
+        - .meta.json has no prompt_template, build_prompt_template, or
+          query_prompt_template keys (or embedding_options is empty/None)
+        """
+        # Setup mocks
+        mock_builder = Mock()
+        mock_builder_class.return_value = mock_builder
+
+        cli = LeannCLI()
+
+        # Mock load_documents to return a document so builder is created
+        cli.load_documents = Mock(return_value=[{"text": "test content", "metadata": {}}])
+
+        parser = cli.create_parser()
+
+        args = parser.parse_args(["build", "test-index", "--docs", str(tmp_path), "--force"])
+
+        # Run the build command
+        import asyncio
+
+        asyncio.run(cli.build_index(args))
+
+        # Check that no template keys are present
+        call_kwargs = mock_builder_class.call_args.kwargs
+        if call_kwargs.get("embedding_options"):
+            embedding_options = call_kwargs["embedding_options"]
+
+            # None of the template keys should be present
+            assert "prompt_template" not in embedding_options, (
+                "prompt_template should not be present when no flags provided"
+            )
+            assert "build_prompt_template" not in embedding_options, (
+                "build_prompt_template should not be present when no flags provided"
+            )
+            assert "query_prompt_template" not in embedding_options, (
+                "query_prompt_template should not be present when no flags provided"
+            )
+
+
+class TestPromptTemplateFlowsToComputeEmbeddings:
+    """Tests for template flowing through to compute_embeddings function."""
+
+    @patch("leann.api.compute_embeddings")
+    def test_prompt_template_flows_to_compute_embeddings_via_provider_options(
+        self, mock_compute_embeddings, tmp_path
+    ):
+        """
+        Verify that the prompt template flows from CLI args through LeannBuilder
+        to compute_embeddings() function via provider_options parameter.
+
+        This is an integration test that verifies the complete flow:
+        CLI → embedding_options → LeannBuilder → compute_embeddings(provider_options)
+
+        This test will fail because:
+        1. CLI doesn't capture the argument yet
+        2. embedding_options doesn't include prompt_template
+        3. LeannBuilder doesn't pass it through to compute_embeddings
+        """
+        # Mock compute_embeddings to return dummy embeddings as numpy array
+        import numpy as np
+
+        mock_compute_embeddings.return_value = np.array([[0.1, 0.2, 0.3]], dtype=np.float32)
+
+        # Use real LeannBuilder (not mocked) to test the actual flow
+        cli = LeannCLI()
+
+        # Mock load_documents to return a simple document
+        cli.load_documents = Mock(return_value=[{"text": "test content", "metadata": {}}])
+
+        parser = cli.create_parser()
+
+        template = "search_document: "
+        args = parser.parse_args(
+            [
+                "build",
+                "test-index",
+                "--docs",
+                str(tmp_path),
+                "--embedding-prompt-template",
+                template,
+                "--backend-name",
+                "hnsw",  # Use hnsw backend
+                "--force",  # Force rebuild to ensure index is created
+            ]
+        )
+
+        # This should fail because the flow isn't implemented yet
+        import asyncio
+
+        asyncio.run(cli.build_index(args))
+
+        # Verify compute_embeddings was called with provider_options containing prompt_template
+        assert mock_compute_embeddings.called, "compute_embeddings should have been called"
+
+        # Check the call arguments
+        call_kwargs = mock_compute_embeddings.call_args.kwargs
+        assert "provider_options" in call_kwargs, (
+            "compute_embeddings should receive provider_options parameter"
+        )
+
+        provider_options = call_kwargs["provider_options"]
+        assert provider_options is not None, "provider_options should not be None"
+        assert "prompt_template" in provider_options, (
+            "provider_options should contain prompt_template key"
+        )
+        assert provider_options["prompt_template"] == template, (
+            f"Template should be '{template}', got {provider_options.get('prompt_template')}"
+        )
+
+
+class TestPromptTemplateArgumentHelp:
+    """Tests for argument help text and documentation."""
+
+    def test_build_command_prompt_template_has_help_text(self):
+        """
+        Verify that --embedding-prompt-template has descriptive help text.
+
+        Good help text is crucial for CLI usability.
+        """
+        cli = LeannCLI()
+        parser = cli.create_parser()
+
+        # Get the build subparser
+        # This is a bit tricky - we need to parse to get the help
+        # We'll check that the help includes relevant keywords
+        import io
+        from contextlib import redirect_stdout
+
+        f = io.StringIO()
+        try:
+            with redirect_stdout(f):
+                parser.parse_args(["build", "--help"])
+        except SystemExit:
+            pass  # --help causes sys.exit(0)
+
+        help_text = f.getvalue()
+        assert "--embedding-prompt-template" in help_text, (
+            "Help text should mention --embedding-prompt-template"
+        )
+        # Check for keywords that should be in the help
+        help_lower = help_text.lower()
+        assert any(keyword in help_lower for keyword in ["template", "prompt", "prepend"]), (
+            "Help text should explain what the prompt template does"
+        )
+
+    def test_search_command_prompt_template_has_help_text(self):
+        """
+        Verify that search command also has help text for --embedding-prompt-template.
+        """
+        cli = LeannCLI()
+        parser = cli.create_parser()
+
+        import io
+        from contextlib import redirect_stdout
+
+        f = io.StringIO()
+        try:
+            with redirect_stdout(f):
+                parser.parse_args(["search", "--help"])
+        except SystemExit:
+            pass  # --help causes sys.exit(0)
+
+        help_text = f.getvalue()
+        assert "--embedding-prompt-template" in help_text, (
+            "Search help text should mention --embedding-prompt-template"
+        )

tests/test_embedding_prompt_template.py

@@ -0,0 +1,281 @@
+"""Unit tests for prompt template prepending in OpenAI embeddings.
+
+This test suite defines the contract for prompt template functionality that allows
+users to prepend a consistent prompt to all embedding inputs. These tests verify:
+
+1. Template prepending to all input texts before embedding computation
+2. Graceful handling of None/missing provider_options
+3. Empty string template behavior (no-op)
+4. Logging of template application for observability
+5. Template application before token truncation
+
+All tests are written in Red Phase - they should FAIL initially because the
+implementation does not exist yet.
+"""
+
+from unittest.mock import MagicMock, Mock, patch
+
+import numpy as np
+import pytest
+from leann.embedding_compute import compute_embeddings_openai
+
+
+class TestPromptTemplatePrepending:
+    """Tests for prompt template prepending in compute_embeddings_openai."""
+
+    @pytest.fixture
+    def mock_openai_client(self):
+        """Create mock OpenAI client that captures input texts."""
+        mock_client = MagicMock()
+
+        # Mock the embeddings.create response
+        mock_response = Mock()
+        mock_response.data = [
+            Mock(embedding=[0.1, 0.2, 0.3]),
+            Mock(embedding=[0.4, 0.5, 0.6]),
+        ]
+        mock_client.embeddings.create.return_value = mock_response
+
+        return mock_client
+
+    @pytest.fixture
+    def mock_openai_module(self, mock_openai_client, monkeypatch):
+        """Mock the openai module to return our mock client."""
+        # Mock the API key environment variable
+        monkeypatch.setenv("OPENAI_API_KEY", "fake-test-key-for-mocking")
+
+        # openai is imported inside the function, so we need to patch it there
+        with patch("openai.OpenAI", return_value=mock_openai_client) as mock_openai:
+            yield mock_openai
+
+    def test_prompt_template_prepended_to_all_texts(self, mock_openai_module, mock_openai_client):
+        """Verify template is prepended to all input texts.
+
+        When provider_options contains "prompt_template", that template should
+        be prepended to every text in the input list before sending to OpenAI API.
+
+        This is the core functionality: the template acts as a consistent prefix
+        that provides context or instruction for the embedding model.
+        """
+        texts = ["First document", "Second document"]
+        template = "search_document: "
+        provider_options = {"prompt_template": template}
+
+        # Call compute_embeddings_openai with provider_options
+        result = compute_embeddings_openai(
+            texts=texts,
+            model_name="text-embedding-3-small",
+            provider_options=provider_options,
+        )
+
+        # Verify embeddings.create was called with templated texts
+        mock_openai_client.embeddings.create.assert_called_once()
+        call_args = mock_openai_client.embeddings.create.call_args
+
+        # Extract the input texts sent to API
+        sent_texts = call_args.kwargs["input"]
+
+        # Verify template was prepended to all texts
+        assert len(sent_texts) == 2, "Should send same number of texts"
+        assert sent_texts[0] == "search_document: First document", (
+            "Template should be prepended to first text"
+        )
+        assert sent_texts[1] == "search_document: Second document", (
+            "Template should be prepended to second text"
+        )
+
+        # Verify result is valid embeddings array
+        assert isinstance(result, np.ndarray)
+        assert result.shape == (2, 3), "Should return correct shape"
+
+    def test_template_not_applied_when_missing_or_empty(
+        self, mock_openai_module, mock_openai_client
+    ):
+        """Verify template not applied when provider_options is None, missing key, or empty string.
+
+        This consolidated test covers three scenarios where templates should NOT be applied:
+        1. provider_options is None (default behavior)
+        2. provider_options exists but missing 'prompt_template' key
+        3. prompt_template is explicitly set to empty string ""
+
+        In all cases, texts should be sent to the API unchanged.
+        """
+        # Scenario 1: None provider_options
+        texts = ["Original text one", "Original text two"]
+        result = compute_embeddings_openai(
+            texts=texts,
+            model_name="text-embedding-3-small",
+            provider_options=None,
+        )
+        call_args = mock_openai_client.embeddings.create.call_args
+        sent_texts = call_args.kwargs["input"]
+        assert sent_texts[0] == "Original text one", (
+            "Text should be unchanged with None provider_options"
+        )
+        assert sent_texts[1] == "Original text two"
+        assert isinstance(result, np.ndarray)
+        assert result.shape == (2, 3)
+
+        # Reset mock for next scenario
+        mock_openai_client.reset_mock()
+        mock_response = Mock()
+        mock_response.data = [
+            Mock(embedding=[0.1, 0.2, 0.3]),
+            Mock(embedding=[0.4, 0.5, 0.6]),
+        ]
+        mock_openai_client.embeddings.create.return_value = mock_response
+
+        # Scenario 2: Missing 'prompt_template' key
+        texts = ["Text without template", "Another text"]
+        provider_options = {"base_url": "https://api.openai.com/v1"}
+        result = compute_embeddings_openai(
+            texts=texts,
+            model_name="text-embedding-3-small",
+            provider_options=provider_options,
+        )
+        call_args = mock_openai_client.embeddings.create.call_args
+        sent_texts = call_args.kwargs["input"]
+        assert sent_texts[0] == "Text without template", "Text should be unchanged with missing key"
+        assert sent_texts[1] == "Another text"
+        assert isinstance(result, np.ndarray)
+
+        # Reset mock for next scenario
+        mock_openai_client.reset_mock()
+        mock_openai_client.embeddings.create.return_value = mock_response
+
+        # Scenario 3: Empty string template
+        texts = ["Text one", "Text two"]
+        provider_options = {"prompt_template": ""}
+        result = compute_embeddings_openai(
+            texts=texts,
+            model_name="text-embedding-3-small",
+            provider_options=provider_options,
+        )
+        call_args = mock_openai_client.embeddings.create.call_args
+        sent_texts = call_args.kwargs["input"]
+        assert sent_texts[0] == "Text one", "Empty template should not modify text"
+        assert sent_texts[1] == "Text two"
+        assert isinstance(result, np.ndarray)
+
+    def test_prompt_template_with_multiple_batches(self, mock_openai_module, mock_openai_client):
+        """Verify template is prepended in all batches when texts exceed batch size.
+
+        OpenAI API has batch size limits. When input texts are split into
+        multiple batches, the template should be prepended to texts in every batch.
+
+        This ensures consistency across all API calls.
+        """
+        # Create many texts that will be split into multiple batches
+        texts = [f"Document {i}" for i in range(1000)]
+        template = "passage: "
+        provider_options = {"prompt_template": template}
+
+        # Mock multiple batch responses
+        mock_response = Mock()
+        mock_response.data = [Mock(embedding=[0.1, 0.2, 0.3]) for _ in range(1000)]
+        mock_openai_client.embeddings.create.return_value = mock_response
+
+        result = compute_embeddings_openai(
+            texts=texts,
+            model_name="text-embedding-3-small",
+            provider_options=provider_options,
+        )
+
+        # Verify embeddings.create was called multiple times (batching)
+        assert mock_openai_client.embeddings.create.call_count >= 2, (
+            "Should make multiple API calls for large text list"
+        )
+
+        # Verify template was prepended in ALL batches
+        for call in mock_openai_client.embeddings.create.call_args_list:
+            sent_texts = call.kwargs["input"]
+            for text in sent_texts:
+                assert text.startswith(template), (
+                    f"All texts in all batches should start with template. Got: {text}"
+                )
+
+        # Verify result shape
+        assert result.shape[0] == 1000, "Should return embeddings for all texts"
+
+    def test_prompt_template_with_special_characters(self, mock_openai_module, mock_openai_client):
+        """Verify template with special characters is handled correctly.
+
+        Templates may contain special characters, Unicode, newlines, etc.
+        These should all be prepended correctly without encoding issues.
+        """
+        texts = ["Document content"]
+        # Template with various special characters
+        template = "🔍 Search query [EN]: "
+        provider_options = {"prompt_template": template}
+
+        result = compute_embeddings_openai(
+            texts=texts,
+            model_name="text-embedding-3-small",
+            provider_options=provider_options,
+        )
+
+        # Verify special characters in template were preserved
+        call_args = mock_openai_client.embeddings.create.call_args
+        sent_texts = call_args.kwargs["input"]
+
+        assert sent_texts[0] == "🔍 Search query [EN]: Document content", (
+            "Special characters in template should be preserved"
+        )
+
+        assert isinstance(result, np.ndarray)
+
+    def test_prompt_template_integration_with_existing_validation(
+        self, mock_openai_module, mock_openai_client
+    ):
+        """Verify template works with existing input validation.
+
+        compute_embeddings_openai has validation for empty texts and whitespace.
+        Template prepending should happen AFTER validation, so validation errors
+        are thrown based on original texts, not templated texts.
+
+        This ensures users get clear error messages about their input.
+        """
+        # Empty text should still raise ValueError even with template
+        texts = [""]
+        provider_options = {"prompt_template": "prefix: "}
+
+        with pytest.raises(ValueError, match="empty/invalid"):
+            compute_embeddings_openai(
+                texts=texts,
+                model_name="text-embedding-3-small",
+                provider_options=provider_options,
+            )
+
+    def test_prompt_template_with_api_key_and_base_url(
+        self, mock_openai_module, mock_openai_client
+    ):
+        """Verify template works alongside other provider_options.
+
+        provider_options may contain multiple settings: prompt_template,
+        base_url, api_key. All should work together correctly.
+        """
+        texts = ["Test document"]
+        provider_options = {
+            "prompt_template": "embed: ",
+            "base_url": "https://custom.api.com/v1",
+            "api_key": "test-key-123",
+        }
+
+        result = compute_embeddings_openai(
+            texts=texts,
+            model_name="text-embedding-3-small",
+            provider_options=provider_options,
+        )
+
+        # Verify template was applied
+        call_args = mock_openai_client.embeddings.create.call_args
+        sent_texts = call_args.kwargs["input"]
+        assert sent_texts[0] == "embed: Test document"
+
+        # Verify OpenAI client was created with correct base_url
+        mock_openai_module.assert_called()
+        client_init_kwargs = mock_openai_module.call_args.kwargs
+        assert client_init_kwargs["base_url"] == "https://custom.api.com/v1"
+        assert client_init_kwargs["api_key"] == "test-key-123"
+
+        assert isinstance(result, np.ndarray)

tests/test_lmstudio_bridge.py

@@ -0,0 +1,315 @@
+"""Unit tests for LM Studio TypeScript SDK bridge functionality.
+
+This test suite defines the contract for the LM Studio SDK bridge that queries
+model context length via Node.js subprocess. These tests verify:
+
+1. Successful SDK query returns context length
+2. Graceful fallback when Node.js not installed (FileNotFoundError)
+3. Graceful fallback when SDK not installed (npm error)
+4. Timeout handling (subprocess.TimeoutExpired)
+5. Invalid JSON response handling
+
+All tests are written in Red Phase - they should FAIL initially because the
+`_query_lmstudio_context_limit` function does not exist yet.
+
+The function contract:
+- Inputs: model_name (str), base_url (str, WebSocket format "ws://localhost:1234")
+- Outputs: context_length (int) or None on error
+- Requirements:
+  1. Call Node.js with inline JavaScript using @lmstudio/sdk
+  2. 10-second timeout (accounts for Node.js startup)
+  3. Graceful fallback on any error (returns None, doesn't raise)
+  4. Parse JSON response with contextLength field
+  5. Log errors at debug level (not warning/error)
+"""
+
+import subprocess
+from unittest.mock import Mock
+
+import pytest
+
+# Try to import the function - if it doesn't exist, tests will fail as expected
+try:
+    from leann.embedding_compute import _query_lmstudio_context_limit
+except ImportError:
+    # Function doesn't exist yet (Red Phase) - create a placeholder that will fail
+    def _query_lmstudio_context_limit(*args, **kwargs):
+        raise NotImplementedError(
+            "_query_lmstudio_context_limit not implemented yet - this is the Red Phase"
+        )
+
+
+class TestLMStudioBridge:
+    """Tests for LM Studio TypeScript SDK bridge integration."""
+
+    def test_query_lmstudio_success(self, monkeypatch):
+        """Verify successful SDK query returns context length.
+
+        When the Node.js subprocess successfully queries the LM Studio SDK,
+        it should return a JSON response with contextLength field. The function
+        should parse this and return the integer context length.
+        """
+
+        def mock_run(*args, **kwargs):
+            # Verify timeout is set to 10 seconds
+            assert kwargs.get("timeout") == 10, "Should use 10-second timeout for Node.js startup"
+
+            # Verify capture_output and text=True are set
+            assert kwargs.get("capture_output") is True, "Should capture stdout/stderr"
+            assert kwargs.get("text") is True, "Should decode output as text"
+
+            # Return successful JSON response
+            mock_result = Mock()
+            mock_result.returncode = 0
+            mock_result.stdout = '{"contextLength": 8192, "identifier": "custom-model"}'
+            mock_result.stderr = ""
+            return mock_result
+
+        monkeypatch.setattr("subprocess.run", mock_run)
+
+        # Test with typical LM Studio model
+        limit = _query_lmstudio_context_limit(
+            model_name="custom-model", base_url="ws://localhost:1234"
+        )
+
+        assert limit == 8192, "Should return context length from SDK response"
+
+    def test_query_lmstudio_nodejs_not_found(self, monkeypatch):
+        """Verify graceful fallback when Node.js not installed.
+
+        When Node.js is not installed, subprocess.run will raise FileNotFoundError.
+        The function should catch this and return None (graceful fallback to registry).
+        """
+
+        def mock_run(*args, **kwargs):
+            raise FileNotFoundError("node: command not found")
+
+        monkeypatch.setattr("subprocess.run", mock_run)
+
+        limit = _query_lmstudio_context_limit(
+            model_name="custom-model", base_url="ws://localhost:1234"
+        )
+
+        assert limit is None, "Should return None when Node.js not installed"
+
+    def test_query_lmstudio_sdk_not_installed(self, monkeypatch):
+        """Verify graceful fallback when @lmstudio/sdk not installed.
+
+        When the SDK npm package is not installed, Node.js will return non-zero
+        exit code with error message in stderr. The function should detect this
+        and return None.
+        """
+
+        def mock_run(*args, **kwargs):
+            mock_result = Mock()
+            mock_result.returncode = 1
+            mock_result.stdout = ""
+            mock_result.stderr = (
+                "Error: Cannot find module '@lmstudio/sdk'\nRequire stack:\n- /path/to/script.js"
+            )
+            return mock_result
+
+        monkeypatch.setattr("subprocess.run", mock_run)
+
+        limit = _query_lmstudio_context_limit(
+            model_name="custom-model", base_url="ws://localhost:1234"
+        )
+
+        assert limit is None, "Should return None when SDK not installed"
+
+    def test_query_lmstudio_timeout(self, monkeypatch):
+        """Verify graceful fallback when subprocess times out.
+
+        When the Node.js process takes longer than 10 seconds (e.g., LM Studio
+        not responding), subprocess.TimeoutExpired should be raised. The function
+        should catch this and return None.
+        """
+
+        def mock_run(*args, **kwargs):
+            raise subprocess.TimeoutExpired(cmd=["node", "lmstudio_bridge.js"], timeout=10)
+
+        monkeypatch.setattr("subprocess.run", mock_run)
+
+        limit = _query_lmstudio_context_limit(
+            model_name="custom-model", base_url="ws://localhost:1234"
+        )
+
+        assert limit is None, "Should return None on timeout"
+
+    def test_query_lmstudio_invalid_json(self, monkeypatch):
+        """Verify graceful fallback when response is invalid JSON.
+
+        When the subprocess returns malformed JSON (e.g., due to SDK error),
+        json.loads will raise ValueError/JSONDecodeError. The function should
+        catch this and return None.
+        """
+
+        def mock_run(*args, **kwargs):
+            mock_result = Mock()
+            mock_result.returncode = 0
+            mock_result.stdout = "This is not valid JSON"
+            mock_result.stderr = ""
+            return mock_result
+
+        monkeypatch.setattr("subprocess.run", mock_run)
+
+        limit = _query_lmstudio_context_limit(
+            model_name="custom-model", base_url="ws://localhost:1234"
+        )
+
+        assert limit is None, "Should return None when JSON parsing fails"
+
+    def test_query_lmstudio_missing_context_length_field(self, monkeypatch):
+        """Verify graceful fallback when JSON lacks contextLength field.
+
+        When the SDK returns valid JSON but without the expected contextLength
+        field (e.g., error response), the function should return None.
+        """
+
+        def mock_run(*args, **kwargs):
+            mock_result = Mock()
+            mock_result.returncode = 0
+            mock_result.stdout = '{"identifier": "test-model", "error": "Model not found"}'
+            mock_result.stderr = ""
+            return mock_result
+
+        monkeypatch.setattr("subprocess.run", mock_run)
+
+        limit = _query_lmstudio_context_limit(
+            model_name="nonexistent-model", base_url="ws://localhost:1234"
+        )
+
+        assert limit is None, "Should return None when contextLength field missing"
+
+    def test_query_lmstudio_null_context_length(self, monkeypatch):
+        """Verify graceful fallback when contextLength is null.
+
+        When the SDK returns contextLength: null (model couldn't be loaded),
+        the function should return None for registry fallback.
+        """
+
+        def mock_run(*args, **kwargs):
+            mock_result = Mock()
+            mock_result.returncode = 0
+            mock_result.stdout = '{"contextLength": null, "identifier": "test-model"}'
+            mock_result.stderr = ""
+            return mock_result
+
+        monkeypatch.setattr("subprocess.run", mock_run)
+
+        limit = _query_lmstudio_context_limit(
+            model_name="test-model", base_url="ws://localhost:1234"
+        )
+
+        assert limit is None, "Should return None when contextLength is null"
+
+    def test_query_lmstudio_zero_context_length(self, monkeypatch):
+        """Verify graceful fallback when contextLength is zero.
+
+        When the SDK returns contextLength: 0 (invalid value), the function
+        should return None to trigger registry fallback.
+        """
+
+        def mock_run(*args, **kwargs):
+            mock_result = Mock()
+            mock_result.returncode = 0
+            mock_result.stdout = '{"contextLength": 0, "identifier": "test-model"}'
+            mock_result.stderr = ""
+            return mock_result
+
+        monkeypatch.setattr("subprocess.run", mock_run)
+
+        limit = _query_lmstudio_context_limit(
+            model_name="test-model", base_url="ws://localhost:1234"
+        )
+
+        assert limit is None, "Should return None when contextLength is zero"
+
+    def test_query_lmstudio_with_custom_port(self, monkeypatch):
+        """Verify SDK query works with non-default WebSocket port.
+
+        LM Studio can run on custom ports. The function should pass the
+        provided base_url to the Node.js subprocess.
+        """
+
+        def mock_run(*args, **kwargs):
+            # Verify the base_url argument is passed correctly
+            command = args[0] if args else kwargs.get("args", [])
+            assert "ws://localhost:8080" in " ".join(command), (
+                "Should pass custom port to subprocess"
+            )
+
+            mock_result = Mock()
+            mock_result.returncode = 0
+            mock_result.stdout = '{"contextLength": 4096, "identifier": "custom-model"}'
+            mock_result.stderr = ""
+            return mock_result
+
+        monkeypatch.setattr("subprocess.run", mock_run)
+
+        limit = _query_lmstudio_context_limit(
+            model_name="custom-model", base_url="ws://localhost:8080"
+        )
+
+        assert limit == 4096, "Should work with custom WebSocket port"
+
+    @pytest.mark.parametrize(
+        "context_length,expected",
+        [
+            (512, 512),  # Small context
+            (2048, 2048),  # Common context
+            (8192, 8192),  # Large context
+            (32768, 32768),  # Very large context
+        ],
+    )
+    def test_query_lmstudio_various_context_lengths(self, monkeypatch, context_length, expected):
+        """Verify SDK query handles various context length values.
+
+        Different models have different context lengths. The function should
+        correctly parse and return any positive integer value.
+        """
+
+        def mock_run(*args, **kwargs):
+            mock_result = Mock()
+            mock_result.returncode = 0
+            mock_result.stdout = f'{{"contextLength": {context_length}, "identifier": "test"}}'
+            mock_result.stderr = ""
+            return mock_result
+
+        monkeypatch.setattr("subprocess.run", mock_run)
+
+        limit = _query_lmstudio_context_limit(
+            model_name="test-model", base_url="ws://localhost:1234"
+        )
+
+        assert limit == expected, f"Should return {expected} for context length {context_length}"
+
+    def test_query_lmstudio_logs_at_debug_level(self, monkeypatch, caplog):
+        """Verify errors are logged at DEBUG level, not WARNING/ERROR.
+
+        Following the graceful fallback pattern from Ollama implementation,
+        errors should be logged at debug level to avoid alarming users when
+        fallback to registry works fine.
+        """
+        import logging
+
+        caplog.set_level(logging.DEBUG, logger="leann.embedding_compute")
+
+        def mock_run(*args, **kwargs):
+            raise FileNotFoundError("node: command not found")
+
+        monkeypatch.setattr("subprocess.run", mock_run)
+
+        _query_lmstudio_context_limit(model_name="test-model", base_url="ws://localhost:1234")
+
+        # Check that debug logging occurred (not warning/error)
+        debug_logs = [record for record in caplog.records if record.levelname == "DEBUG"]
+        assert len(debug_logs) > 0, "Should log error at DEBUG level"
+
+        # Verify no WARNING or ERROR logs
+        warning_or_error_logs = [
+            record for record in caplog.records if record.levelname in ["WARNING", "ERROR"]
+        ]
+        assert len(warning_or_error_logs) == 0, (
+            "Should not log at WARNING/ERROR level for expected failures"
+        )

tests/test_prompt_template_e2e.py

@@ -0,0 +1,400 @@
+"""End-to-end integration tests for prompt template and token limit features.
+
+These tests verify real-world functionality with live services:
+- OpenAI-compatible APIs (OpenAI, LM Studio) with prompt template support
+- Ollama with dynamic token limit detection
+- Hybrid token limit discovery mechanism
+
+Run with: pytest tests/test_prompt_template_e2e.py -v -s
+Skip if services unavailable: pytest tests/test_prompt_template_e2e.py -m "not integration"
+
+Prerequisites:
+1. LM Studio running with embedding model: http://localhost:1234
+2. [Optional] Ollama running: ollama serve
+3. [Optional] Ollama model: ollama pull nomic-embed-text
+4. [Optional] Node.js + @lmstudio/sdk for context length detection
+"""
+
+import logging
+import socket
+
+import numpy as np
+import pytest
+import requests
+from leann.embedding_compute import (
+    compute_embeddings_ollama,
+    compute_embeddings_openai,
+    get_model_token_limit,
+)
+
+# Test markers for conditional execution
+pytestmark = pytest.mark.integration
+
+logger = logging.getLogger(__name__)
+
+
+def check_service_available(host: str, port: int, timeout: float = 2.0) -> bool:
+    """Check if a service is available on the given host:port."""
+    try:
+        sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+        sock.settimeout(timeout)
+        result = sock.connect_ex((host, port))
+        sock.close()
+        return result == 0
+    except Exception:
+        return False
+
+
+def check_ollama_available() -> bool:
+    """Check if Ollama service is available."""
+    if not check_service_available("localhost", 11434):
+        return False
+    try:
+        response = requests.get("http://localhost:11434/api/tags", timeout=2.0)
+        return response.status_code == 200
+    except Exception:
+        return False
+
+
+def check_lmstudio_available() -> bool:
+    """Check if LM Studio service is available."""
+    if not check_service_available("localhost", 1234):
+        return False
+    try:
+        response = requests.get("http://localhost:1234/v1/models", timeout=2.0)
+        return response.status_code == 200
+    except Exception:
+        return False
+
+
+def get_lmstudio_first_model() -> str:
+    """Get the first available model from LM Studio."""
+    try:
+        response = requests.get("http://localhost:1234/v1/models", timeout=5.0)
+        data = response.json()
+        models = data.get("data", [])
+        if models:
+            return models[0]["id"]
+    except Exception:
+        pass
+    return None
+
+
+class TestPromptTemplateOpenAI:
+    """End-to-end tests for prompt template with OpenAI-compatible APIs (LM Studio)."""
+
+    @pytest.mark.skipif(
+        not check_lmstudio_available(), reason="LM Studio service not available on localhost:1234"
+    )
+    def test_lmstudio_embedding_with_prompt_template(self):
+        """Test prompt templates with LM Studio using OpenAI-compatible API."""
+        model_name = get_lmstudio_first_model()
+        if not model_name:
+            pytest.skip("No models loaded in LM Studio")
+
+        texts = ["artificial intelligence", "machine learning"]
+        prompt_template = "search_query: "
+
+        # Get embeddings with prompt template via provider_options
+        provider_options = {"prompt_template": prompt_template}
+        embeddings = compute_embeddings_openai(
+            texts=texts,
+            model_name=model_name,
+            base_url="http://localhost:1234/v1",
+            api_key="lm-studio",  # LM Studio doesn't require real key
+            provider_options=provider_options,
+        )
+
+        assert embeddings is not None
+        assert len(embeddings) == 2
+        assert all(isinstance(emb, np.ndarray) for emb in embeddings)
+        assert all(len(emb) > 0 for emb in embeddings)
+
+        logger.info(
+            f"✓ LM Studio embeddings with prompt template: {len(embeddings)} vectors, {len(embeddings[0])} dimensions"
+        )
+
+    @pytest.mark.skipif(not check_lmstudio_available(), reason="LM Studio service not available")
+    def test_lmstudio_prompt_template_affects_embeddings(self):
+        """Verify that prompt templates actually change embedding values."""
+        model_name = get_lmstudio_first_model()
+        if not model_name:
+            pytest.skip("No models loaded in LM Studio")
+
+        text = "machine learning"
+        base_url = "http://localhost:1234/v1"
+        api_key = "lm-studio"
+
+        # Get embeddings without template
+        embeddings_no_template = compute_embeddings_openai(
+            texts=[text],
+            model_name=model_name,
+            base_url=base_url,
+            api_key=api_key,
+            provider_options={},
+        )
+
+        # Get embeddings with template
+        embeddings_with_template = compute_embeddings_openai(
+            texts=[text],
+            model_name=model_name,
+            base_url=base_url,
+            api_key=api_key,
+            provider_options={"prompt_template": "search_query: "},
+        )
+
+        # Embeddings should be different when template is applied
+        assert not np.allclose(embeddings_no_template[0], embeddings_with_template[0])
+
+        logger.info("✓ Prompt template changes embedding values as expected")
+
+
+class TestPromptTemplateOllama:
+    """End-to-end tests for prompt template with Ollama."""
+
+    @pytest.mark.skipif(
+        not check_ollama_available(), reason="Ollama service not available on localhost:11434"
+    )
+    def test_ollama_embedding_with_prompt_template(self):
+        """Test prompt templates with Ollama using any available embedding model."""
+        # Get any available embedding model
+        try:
+            response = requests.get("http://localhost:11434/api/tags", timeout=2.0)
+            models = response.json().get("models", [])
+
+            embedding_models = []
+            for model in models:
+                name = model["name"]
+                base_name = name.split(":")[0]
+                if any(emb in base_name for emb in ["embed", "bge", "minilm", "e5", "nomic"]):
+                    embedding_models.append(name)
+
+            if not embedding_models:
+                pytest.skip("No embedding models available in Ollama")
+
+            model_name = embedding_models[0]
+
+            texts = ["artificial intelligence", "machine learning"]
+            prompt_template = "search_query: "
+
+            # Get embeddings with prompt template via provider_options
+            provider_options = {"prompt_template": prompt_template}
+            embeddings = compute_embeddings_ollama(
+                texts=texts,
+                model_name=model_name,
+                is_build=False,
+                host="http://localhost:11434",
+                provider_options=provider_options,
+            )
+
+            assert embeddings is not None
+            assert len(embeddings) == 2
+            assert all(isinstance(emb, np.ndarray) for emb in embeddings)
+            assert all(len(emb) > 0 for emb in embeddings)
+
+            logger.info(
+                f"✓ Ollama embeddings with prompt template: {len(embeddings)} vectors, {len(embeddings[0])} dimensions"
+            )
+
+        except Exception as e:
+            pytest.skip(f"Could not test Ollama prompt template: {e}")
+
+    @pytest.mark.skipif(not check_ollama_available(), reason="Ollama service not available")
+    def test_ollama_prompt_template_affects_embeddings(self):
+        """Verify that prompt templates actually change embedding values with Ollama."""
+        # Get any available embedding model
+        try:
+            response = requests.get("http://localhost:11434/api/tags", timeout=2.0)
+            models = response.json().get("models", [])
+
+            embedding_models = []
+            for model in models:
+                name = model["name"]
+                base_name = name.split(":")[0]
+                if any(emb in base_name for emb in ["embed", "bge", "minilm", "e5", "nomic"]):
+                    embedding_models.append(name)
+
+            if not embedding_models:
+                pytest.skip("No embedding models available in Ollama")
+
+            model_name = embedding_models[0]
+            text = "machine learning"
+            host = "http://localhost:11434"
+
+            # Get embeddings without template
+            embeddings_no_template = compute_embeddings_ollama(
+                texts=[text], model_name=model_name, is_build=False, host=host, provider_options={}
+            )
+
+            # Get embeddings with template
+            embeddings_with_template = compute_embeddings_ollama(
+                texts=[text],
+                model_name=model_name,
+                is_build=False,
+                host=host,
+                provider_options={"prompt_template": "search_query: "},
+            )
+
+            # Embeddings should be different when template is applied
+            assert not np.allclose(embeddings_no_template[0], embeddings_with_template[0])
+
+            logger.info("✓ Ollama prompt template changes embedding values as expected")
+
+        except Exception as e:
+            pytest.skip(f"Could not test Ollama prompt template: {e}")
+
+
+class TestLMStudioSDK:
+    """End-to-end tests for LM Studio SDK integration."""
+
+    @pytest.mark.skipif(not check_lmstudio_available(), reason="LM Studio service not available")
+    def test_lmstudio_model_listing(self):
+        """Test that we can list models from LM Studio."""
+        try:
+            response = requests.get("http://localhost:1234/v1/models", timeout=5.0)
+            assert response.status_code == 200
+
+            data = response.json()
+            assert "data" in data
+
+            models = data["data"]
+            logger.info(f"✓ LM Studio models available: {len(models)}")
+
+            if models:
+                logger.info(f"  First model: {models[0].get('id', 'unknown')}")
+        except Exception as e:
+            pytest.skip(f"LM Studio API error: {e}")
+
+    @pytest.mark.skipif(not check_lmstudio_available(), reason="LM Studio service not available")
+    def test_lmstudio_sdk_context_length_detection(self):
+        """Test context length detection via LM Studio SDK bridge (requires Node.js + SDK)."""
+        model_name = get_lmstudio_first_model()
+        if not model_name:
+            pytest.skip("No models loaded in LM Studio")
+
+        try:
+            from leann.embedding_compute import _query_lmstudio_context_limit
+
+            # SDK requires WebSocket URL (ws://)
+            context_length = _query_lmstudio_context_limit(
+                model_name=model_name, base_url="ws://localhost:1234"
+            )
+
+            if context_length is None:
+                logger.warning(
+                    "⚠ LM Studio SDK bridge returned None (Node.js or SDK may not be available)"
+                )
+                pytest.skip("Node.js or @lmstudio/sdk not available - SDK bridge unavailable")
+            else:
+                assert context_length > 0
+                logger.info(
+                    f"✓ LM Studio context length detected via SDK: {context_length} for {model_name}"
+                )
+
+        except ImportError:
+            pytest.skip("_query_lmstudio_context_limit not implemented yet")
+        except Exception as e:
+            logger.error(f"LM Studio SDK test error: {e}")
+            raise
+
+
+class TestOllamaTokenLimit:
+    """End-to-end tests for Ollama token limit discovery."""
+
+    @pytest.mark.skipif(not check_ollama_available(), reason="Ollama service not available")
+    def test_ollama_token_limit_detection(self):
+        """Test dynamic token limit detection from Ollama /api/show endpoint."""
+        # Get any available embedding model
+        try:
+            response = requests.get("http://localhost:11434/api/tags", timeout=2.0)
+            models = response.json().get("models", [])
+
+            embedding_models = []
+            for model in models:
+                name = model["name"]
+                base_name = name.split(":")[0]
+                if any(emb in base_name for emb in ["embed", "bge", "minilm", "e5", "nomic"]):
+                    embedding_models.append(name)
+
+            if not embedding_models:
+                pytest.skip("No embedding models available in Ollama")
+
+            test_model = embedding_models[0]
+
+            # Test token limit detection
+            limit = get_model_token_limit(model_name=test_model, base_url="http://localhost:11434")
+
+            assert limit > 0
+            logger.info(f"✓ Ollama token limit detected: {limit} for {test_model}")
+
+        except Exception as e:
+            pytest.skip(f"Could not test Ollama token detection: {e}")
+
+
+class TestHybridTokenLimit:
+    """End-to-end tests for hybrid token limit discovery mechanism."""
+
+    def test_hybrid_discovery_registry_fallback(self):
+        """Test fallback to static registry for known OpenAI models."""
+        # Use a known OpenAI model (should be in registry)
+        limit = get_model_token_limit(
+            model_name="text-embedding-3-small",
+            base_url="http://fake-server:9999",  # Fake URL to force registry lookup
+        )
+
+        # text-embedding-3-small should have 8192 in registry
+        assert limit == 8192
+        logger.info(f"✓ Hybrid discovery (registry fallback): {limit} tokens")
+
+    def test_hybrid_discovery_default_fallback(self):
+        """Test fallback to safe default for completely unknown models."""
+        limit = get_model_token_limit(
+            model_name="completely-unknown-model-xyz-12345",
+            base_url="http://fake-server:9999",
+            default=512,
+        )
+
+        # Should get the specified default
+        assert limit == 512
+        logger.info(f"✓ Hybrid discovery (default fallback): {limit} tokens")
+
+    @pytest.mark.skipif(not check_ollama_available(), reason="Ollama service not available")
+    def test_hybrid_discovery_ollama_dynamic_first(self):
+        """Test that Ollama models use dynamic discovery first."""
+        # Get any available embedding model
+        try:
+            response = requests.get("http://localhost:11434/api/tags", timeout=2.0)
+            models = response.json().get("models", [])
+
+            embedding_models = []
+            for model in models:
+                name = model["name"]
+                base_name = name.split(":")[0]
+                if any(emb in base_name for emb in ["embed", "bge", "minilm", "e5", "nomic"]):
+                    embedding_models.append(name)
+
+            if not embedding_models:
+                pytest.skip("No embedding models available in Ollama")
+
+            test_model = embedding_models[0]
+
+            # Should query Ollama /api/show dynamically
+            limit = get_model_token_limit(model_name=test_model, base_url="http://localhost:11434")
+
+            assert limit > 0
+            logger.info(f"✓ Hybrid discovery (Ollama dynamic): {limit} tokens for {test_model}")
+
+        except Exception as e:
+            pytest.skip(f"Could not test hybrid Ollama discovery: {e}")
+
+
+if __name__ == "__main__":
+    print("\n" + "=" * 70)
+    print("INTEGRATION TEST SUITE - Real Service Testing")
+    print("=" * 70)
+    print("\nThese tests require live services:")
+    print("  • LM Studio: http://localhost:1234 (with embedding model loaded)")
+    print("  • [Optional] Ollama: http://localhost:11434")
+    print("  • [Optional] Node.js + @lmstudio/sdk for SDK bridge tests")
+    print("\nRun with: pytest tests/test_prompt_template_e2e.py -v -s")
+    print("=" * 70 + "\n")

tests/test_prompt_template_persistence.py

@@ -0,0 +1,808 @@
+"""
+Integration tests for prompt template metadata persistence and reuse.
+
+These tests verify the complete lifecycle of prompt template persistence:
+1. Template is saved to .meta.json during index build
+2. Template is automatically loaded during search operations
+3. Template can be overridden with explicit flag during search
+4. Template is reused during chat/ask operations
+
+These are integration tests that:
+- Use real file system with temporary directories
+- Run actual build and search operations
+- Inspect .meta.json file contents directly
+- Mock embedding servers to avoid external dependencies
+- Use small test codebases for fast execution
+
+Expected to FAIL in Red Phase because metadata persistence verification is not yet implemented.
+"""
+
+import json
+import tempfile
+from pathlib import Path
+from unittest.mock import Mock, patch
+
+import numpy as np
+import pytest
+from leann.api import LeannBuilder, LeannSearcher
+
+
+class TestPromptTemplateMetadataPersistence:
+    """Tests for prompt template storage in .meta.json during build."""
+
+    @pytest.fixture
+    def temp_index_dir(self):
+        """Create temporary directory for test indexes."""
+        with tempfile.TemporaryDirectory() as tmpdir:
+            yield Path(tmpdir)
+
+    @pytest.fixture
+    def mock_embeddings(self):
+        """Mock compute_embeddings to return dummy embeddings."""
+        with patch("leann.api.compute_embeddings") as mock_compute:
+            # Return dummy embeddings as numpy array
+            mock_compute.return_value = np.array([[0.1, 0.2, 0.3]], dtype=np.float32)
+            yield mock_compute
+
+    def test_prompt_template_saved_to_metadata(self, temp_index_dir, mock_embeddings):
+        """
+        Verify that when build is run with embedding_options containing prompt_template,
+        the template value is saved to .meta.json file.
+
+        This is the core persistence requirement - templates must be saved to allow
+        reuse in subsequent search operations without re-specifying the flag.
+
+        Expected failure: .meta.json exists but doesn't contain embedding_options
+        with prompt_template, or the value is not persisted correctly.
+        """
+        # Setup test data
+        index_path = temp_index_dir / "test_index.leann"
+        template = "search_document: "
+
+        # Build index with prompt template in embedding_options
+        builder = LeannBuilder(
+            backend_name="hnsw",
+            embedding_model="text-embedding-3-small",
+            embedding_mode="openai",
+            embedding_options={"prompt_template": template},
+        )
+
+        # Add a simple document
+        builder.add_text("This is a test document for indexing")
+
+        # Build the index
+        builder.build_index(str(index_path))
+
+        # Verify .meta.json was created and contains the template
+        meta_path = temp_index_dir / "test_index.leann.meta.json"
+        assert meta_path.exists(), ".meta.json file should be created during build"
+
+        # Read and parse metadata
+        with open(meta_path, encoding="utf-8") as f:
+            meta_data = json.load(f)
+
+        # Verify embedding_options exists in metadata
+        assert "embedding_options" in meta_data, (
+            "embedding_options should be saved to .meta.json when provided"
+        )
+
+        # Verify prompt_template is in embedding_options
+        embedding_options = meta_data["embedding_options"]
+        assert "prompt_template" in embedding_options, (
+            "prompt_template should be saved within embedding_options"
+        )
+
+        # Verify the template value matches what we provided
+        assert embedding_options["prompt_template"] == template, (
+            f"Template should be '{template}', got '{embedding_options.get('prompt_template')}'"
+        )
+
+    def test_prompt_template_absent_when_not_provided(self, temp_index_dir, mock_embeddings):
+        """
+        Verify that when no prompt template is provided during build,
+        .meta.json either doesn't have embedding_options or prompt_template key.
+
+        This ensures clean metadata without unnecessary keys when features aren't used.
+
+        Expected behavior: Build succeeds, .meta.json doesn't contain prompt_template.
+        """
+        index_path = temp_index_dir / "test_no_template.leann"
+
+        # Build index WITHOUT prompt template
+        builder = LeannBuilder(
+            backend_name="hnsw",
+            embedding_model="text-embedding-3-small",
+            embedding_mode="openai",
+            # No embedding_options provided
+        )
+
+        builder.add_text("Document without template")
+        builder.build_index(str(index_path))
+
+        # Verify metadata
+        meta_path = temp_index_dir / "test_no_template.leann.meta.json"
+        assert meta_path.exists()
+
+        with open(meta_path, encoding="utf-8") as f:
+            meta_data = json.load(f)
+
+        # If embedding_options exists, it should not contain prompt_template
+        if "embedding_options" in meta_data:
+            embedding_options = meta_data["embedding_options"]
+            assert "prompt_template" not in embedding_options, (
+                "prompt_template should not be in metadata when not provided"
+            )
+
+
+class TestPromptTemplateAutoLoadOnSearch:
+    """Tests for automatic loading of prompt template during search operations.
+
+    NOTE: Over-mocked test removed (test_prompt_template_auto_loaded_on_search).
+    This functionality is now comprehensively tested by TestQueryPromptTemplateAutoLoad
+    which uses simpler mocking and doesn't hang.
+    """
+
+    @pytest.fixture
+    def temp_index_dir(self):
+        """Create temporary directory for test indexes."""
+        with tempfile.TemporaryDirectory() as tmpdir:
+            yield Path(tmpdir)
+
+    @pytest.fixture
+    def mock_embeddings(self):
+        """Mock compute_embeddings to capture calls and return dummy embeddings."""
+        with patch("leann.api.compute_embeddings") as mock_compute:
+            mock_compute.return_value = np.array([[0.1, 0.2, 0.3]], dtype=np.float32)
+            yield mock_compute
+
+    def test_search_without_template_in_metadata(self, temp_index_dir, mock_embeddings):
+        """
+        Verify that searching an index built WITHOUT a prompt template
+        works correctly (backward compatibility).
+
+        The searcher should handle missing prompt_template gracefully.
+
+        Expected behavior: Search succeeds, no template is used.
+        """
+        # Build index without template
+        index_path = temp_index_dir / "no_template.leann"
+
+        builder = LeannBuilder(
+            backend_name="hnsw",
+            embedding_model="text-embedding-3-small",
+            embedding_mode="openai",
+        )
+        builder.add_text("Document without template")
+        builder.build_index(str(index_path))
+
+        # Reset mocks
+        mock_embeddings.reset_mock()
+
+        # Create searcher and search
+        searcher = LeannSearcher(index_path=str(index_path))
+
+        # Verify no template in embedding_options
+        assert "prompt_template" not in searcher.embedding_options, (
+            "Searcher should not have prompt_template when not in metadata"
+        )
+
+
+class TestQueryPromptTemplateAutoLoad:
+    """Tests for automatic loading of separate query_prompt_template during search (R2).
+
+    These tests verify the new two-template system where:
+    - build_prompt_template: Applied during index building
+    - query_prompt_template: Applied during search operations
+
+    Expected to FAIL in Red Phase (R2) because query template extraction
+    and application is not yet implemented in LeannSearcher.search().
+    """
+
+    @pytest.fixture
+    def temp_index_dir(self):
+        """Create temporary directory for test indexes."""
+        with tempfile.TemporaryDirectory() as tmpdir:
+            yield Path(tmpdir)
+
+    @pytest.fixture
+    def mock_compute_embeddings(self):
+        """Mock compute_embeddings to capture calls and return dummy embeddings."""
+        with patch("leann.embedding_compute.compute_embeddings") as mock_compute:
+            mock_compute.return_value = np.array([[0.1, 0.2, 0.3]], dtype=np.float32)
+            yield mock_compute
+
+    def test_search_auto_loads_query_template(self, temp_index_dir, mock_compute_embeddings):
+        """
+        Verify that search() automatically loads and applies query_prompt_template from .meta.json.
+
+        Given: Index built with separate build_prompt_template and query_prompt_template
+        When: LeannSearcher.search("my query") is called
+        Then: Query embedding is computed with "query: my query" (query template applied)
+
+        This is the core R2 requirement - query templates must be auto-loaded and applied
+        during search without user intervention.
+
+        Expected failure: compute_embeddings called with raw "my query" instead of
+        "query: my query" because query template extraction is not implemented.
+        """
+        # Setup: Build index with separate templates in new format
+        index_path = temp_index_dir / "query_template.leann"
+
+        builder = LeannBuilder(
+            backend_name="hnsw",
+            embedding_model="text-embedding-3-small",
+            embedding_mode="openai",
+            embedding_options={
+                "build_prompt_template": "doc: ",
+                "query_prompt_template": "query: ",
+            },
+        )
+        builder.add_text("Test document")
+        builder.build_index(str(index_path))
+
+        # Reset mock to ignore build calls
+        mock_compute_embeddings.reset_mock()
+
+        # Act: Search with query
+        searcher = LeannSearcher(index_path=str(index_path))
+
+        # Mock the backend search to avoid actual search
+        with patch.object(searcher.backend_impl, "search") as mock_backend_search:
+            mock_backend_search.return_value = {
+                "labels": [["test_id_0"]],  # IDs (nested list for batch support)
+                "distances": [[0.9]],  # Distances (nested list for batch support)
+            }
+
+            searcher.search("my query", top_k=1, recompute_embeddings=False)
+
+        # Assert: compute_embeddings was called with query template applied
+        assert mock_compute_embeddings.called, "compute_embeddings should be called during search"
+
+        # Get the actual text passed to compute_embeddings
+        call_args = mock_compute_embeddings.call_args
+        texts_arg = call_args[0][0]  # First positional arg (list of texts)
+
+        assert len(texts_arg) == 1, "Should compute embedding for one query"
+        assert texts_arg[0] == "query: my query", (
+            f"Query template should be applied: expected 'query: my query', got '{texts_arg[0]}'"
+        )
+
+    def test_search_backward_compat_single_template(self, temp_index_dir, mock_compute_embeddings):
+        """
+        Verify backward compatibility with old single prompt_template format.
+
+        Given: Index with old format (single prompt_template, no query_prompt_template)
+        When: LeannSearcher.search("my query") is called
+        Then: Query embedding computed with "doc: my query" (old template applied)
+
+        This ensures indexes built with the old single-template system continue
+        to work correctly with the new search implementation.
+
+        Expected failure: Old template not recognized/applied because backward
+        compatibility logic is not implemented.
+        """
+        # Setup: Build index with old single-template format
+        index_path = temp_index_dir / "old_template.leann"
+
+        builder = LeannBuilder(
+            backend_name="hnsw",
+            embedding_model="text-embedding-3-small",
+            embedding_mode="openai",
+            embedding_options={"prompt_template": "doc: "},  # Old format
+        )
+        builder.add_text("Test document")
+        builder.build_index(str(index_path))
+
+        # Reset mock
+        mock_compute_embeddings.reset_mock()
+
+        # Act: Search
+        searcher = LeannSearcher(index_path=str(index_path))
+
+        with patch.object(searcher.backend_impl, "search") as mock_backend_search:
+            mock_backend_search.return_value = {"labels": [["test_id_0"]], "distances": [[0.9]]}
+
+            searcher.search("my query", top_k=1, recompute_embeddings=False)
+
+        # Assert: Old template was applied
+        call_args = mock_compute_embeddings.call_args
+        texts_arg = call_args[0][0]
+
+        assert texts_arg[0] == "doc: my query", (
+            f"Old prompt_template should be applied for backward compatibility: "
+            f"expected 'doc: my query', got '{texts_arg[0]}'"
+        )
+
+    def test_search_backward_compat_no_template(self, temp_index_dir, mock_compute_embeddings):
+        """
+        Verify backward compatibility when no template is present in .meta.json.
+
+        Given: Index with no template in .meta.json (very old indexes)
+        When: LeannSearcher.search("my query") is called
+        Then: Query embedding computed with "my query" (no template, raw query)
+
+        This ensures the most basic backward compatibility - indexes without
+        any template support continue to work as before.
+
+        Expected failure: May fail if default template is incorrectly applied,
+        or if missing template causes error.
+        """
+        # Setup: Build index without any template
+        index_path = temp_index_dir / "no_template.leann"
+
+        builder = LeannBuilder(
+            backend_name="hnsw",
+            embedding_model="text-embedding-3-small",
+            embedding_mode="openai",
+            # No embedding_options at all
+        )
+        builder.add_text("Test document")
+        builder.build_index(str(index_path))
+
+        # Reset mock
+        mock_compute_embeddings.reset_mock()
+
+        # Act: Search
+        searcher = LeannSearcher(index_path=str(index_path))
+
+        with patch.object(searcher.backend_impl, "search") as mock_backend_search:
+            mock_backend_search.return_value = {"labels": [["test_id_0"]], "distances": [[0.9]]}
+
+            searcher.search("my query", top_k=1, recompute_embeddings=False)
+
+        # Assert: No template applied (raw query)
+        call_args = mock_compute_embeddings.call_args
+        texts_arg = call_args[0][0]
+
+        assert texts_arg[0] == "my query", (
+            f"No template should be applied when missing from metadata: "
+            f"expected 'my query', got '{texts_arg[0]}'"
+        )
+
+    def test_search_override_via_provider_options(self, temp_index_dir, mock_compute_embeddings):
+        """
+        Verify that explicit provider_options can override stored query template.
+
+        Given: Index with query_prompt_template: "query: "
+        When: search() called with provider_options={"prompt_template": "override: "}
+        Then: Query embedding computed with "override: test" (override takes precedence)
+
+        This enables users to experiment with different query templates without
+        rebuilding the index, or to handle special query types differently.
+
+        Expected failure: provider_options parameter is accepted via **kwargs but
+        not used. Query embedding computed with raw "test" instead of "override: test"
+        because override logic is not implemented.
+        """
+        # Setup: Build index with query template
+        index_path = temp_index_dir / "override_template.leann"
+
+        builder = LeannBuilder(
+            backend_name="hnsw",
+            embedding_model="text-embedding-3-small",
+            embedding_mode="openai",
+            embedding_options={
+                "build_prompt_template": "doc: ",
+                "query_prompt_template": "query: ",
+            },
+        )
+        builder.add_text("Test document")
+        builder.build_index(str(index_path))
+
+        # Reset mock
+        mock_compute_embeddings.reset_mock()
+
+        # Act: Search with override
+        searcher = LeannSearcher(index_path=str(index_path))
+
+        with patch.object(searcher.backend_impl, "search") as mock_backend_search:
+            mock_backend_search.return_value = {"labels": [["test_id_0"]], "distances": [[0.9]]}
+
+            # This should accept provider_options parameter
+            searcher.search(
+                "test",
+                top_k=1,
+                recompute_embeddings=False,
+                provider_options={"prompt_template": "override: "},
+            )
+
+        # Assert: Override template was applied
+        call_args = mock_compute_embeddings.call_args
+        texts_arg = call_args[0][0]
+
+        assert texts_arg[0] == "override: test", (
+            f"Override template should take precedence: "
+            f"expected 'override: test', got '{texts_arg[0]}'"
+        )
+
+
+class TestPromptTemplateReuseInChat:
+    """Tests for prompt template reuse in chat/ask operations."""
+
+    @pytest.fixture
+    def temp_index_dir(self):
+        """Create temporary directory for test indexes."""
+        with tempfile.TemporaryDirectory() as tmpdir:
+            yield Path(tmpdir)
+
+    @pytest.fixture
+    def mock_embeddings(self):
+        """Mock compute_embeddings to return dummy embeddings."""
+        with patch("leann.api.compute_embeddings") as mock_compute:
+            mock_compute.return_value = np.array([[0.1, 0.2, 0.3]], dtype=np.float32)
+            yield mock_compute
+
+    @pytest.fixture
+    def mock_embedding_server_manager(self):
+        """Mock EmbeddingServerManager for chat tests."""
+        with patch("leann.searcher_base.EmbeddingServerManager") as mock_manager_class:
+            mock_manager = Mock()
+            mock_manager.start_server.return_value = (True, 5557)
+            mock_manager_class.return_value = mock_manager
+            yield mock_manager
+
+    @pytest.fixture
+    def index_with_template(self, temp_index_dir, mock_embeddings):
+        """Build an index with a prompt template."""
+        index_path = temp_index_dir / "chat_template_index.leann"
+        template = "document_query: "
+
+        builder = LeannBuilder(
+            backend_name="hnsw",
+            embedding_model="text-embedding-3-small",
+            embedding_mode="openai",
+            embedding_options={"prompt_template": template},
+        )
+
+        builder.add_text("Test document for chat")
+        builder.build_index(str(index_path))
+
+        return str(index_path), template
+
+
+class TestPromptTemplateIntegrationWithEmbeddingModes:
+    """Tests for prompt template compatibility with different embedding modes."""
+
+    @pytest.fixture
+    def temp_index_dir(self):
+        """Create temporary directory for test indexes."""
+        with tempfile.TemporaryDirectory() as tmpdir:
+            yield Path(tmpdir)
+
+    @pytest.mark.parametrize(
+        "mode,model,template,filename_prefix",
+        [
+            (
+                "openai",
+                "text-embedding-3-small",
+                "Represent this for searching: ",
+                "openai_template",
+            ),
+            ("ollama", "nomic-embed-text", "search_query: ", "ollama_template"),
+            ("sentence-transformers", "facebook/contriever", "query: ", "st_template"),
+        ],
+    )
+    def test_prompt_template_metadata_with_embedding_modes(
+        self, temp_index_dir, mode, model, template, filename_prefix
+    ):
+        """Verify prompt template is saved correctly across different embedding modes.
+
+        Tests that prompt templates are persisted to .meta.json for:
+        - OpenAI mode (primary use case)
+        - Ollama mode (also supports templates)
+        - Sentence-transformers mode (saved for forward compatibility)
+
+        Expected behavior: Template is saved to .meta.json regardless of mode.
+        """
+        with patch("leann.api.compute_embeddings") as mock_compute:
+            mock_compute.return_value = np.array([[0.1, 0.2, 0.3]], dtype=np.float32)
+
+            index_path = temp_index_dir / f"{filename_prefix}.leann"
+
+            builder = LeannBuilder(
+                backend_name="hnsw",
+                embedding_model=model,
+                embedding_mode=mode,
+                embedding_options={"prompt_template": template},
+            )
+
+            builder.add_text(f"{mode.capitalize()} test document")
+            builder.build_index(str(index_path))
+
+            # Verify metadata
+            meta_path = temp_index_dir / f"{filename_prefix}.leann.meta.json"
+            with open(meta_path, encoding="utf-8") as f:
+                meta_data = json.load(f)
+
+            assert meta_data["embedding_mode"] == mode
+            # Template should be saved for all modes (even if not used by some)
+            if "embedding_options" in meta_data:
+                assert meta_data["embedding_options"]["prompt_template"] == template
+
+
+class TestQueryTemplateApplicationInComputeEmbedding:
+    """Tests for query template application in compute_query_embedding() (Bug Fix).
+
+    These tests verify that query templates are applied consistently in BOTH
+    code paths (server and fallback) when computing query embeddings.
+
+    This addresses the bug where query templates were only applied in the
+    fallback path, not when using the embedding server (the default path).
+
+    Bug Context:
+    - Issue: Query templates were stored in metadata but only applied during
+      fallback (direct) computation, not when using embedding server
+    - Fix: Move template application to BEFORE any computation path in
+      compute_query_embedding() (searcher_base.py:107-110)
+    - Impact: Critical for models like EmbeddingGemma that require task-specific
+      templates for optimal performance
+
+    These tests ensure the fix works correctly and prevent regression.
+    """
+
+    @pytest.fixture
+    def temp_index_with_template(self):
+        """Create a temporary index with query template in metadata"""
+        with tempfile.TemporaryDirectory() as tmpdir:
+            index_dir = Path(tmpdir)
+            index_file = index_dir / "test.leann"
+            meta_file = index_dir / "test.leann.meta.json"
+
+            # Create minimal metadata with query template
+            metadata = {
+                "version": "1.0",
+                "backend_name": "hnsw",
+                "embedding_model": "text-embedding-embeddinggemma-300m-qat",
+                "dimensions": 768,
+                "embedding_mode": "openai",
+                "backend_kwargs": {
+                    "graph_degree": 32,
+                    "complexity": 64,
+                    "distance_metric": "cosine",
+                },
+                "embedding_options": {
+                    "base_url": "http://localhost:1234/v1",
+                    "api_key": "test-key",
+                    "build_prompt_template": "title: none | text: ",
+                    "query_prompt_template": "task: search result | query: ",
+                },
+            }
+
+            meta_file.write_text(json.dumps(metadata, indent=2))
+
+            # Create minimal HNSW index file (empty is okay for this test)
+            index_file.write_bytes(b"")
+
+            yield str(index_file)
+
+    def test_query_template_applied_in_fallback_path(self, temp_index_with_template):
+        """Test that query template is applied when using fallback (direct) path"""
+        from leann.searcher_base import BaseSearcher
+
+        # Create a concrete implementation for testing
+        class TestSearcher(BaseSearcher):
+            def search(self, query_vectors, top_k, complexity, beam_width=1, **kwargs):
+                return {"labels": [], "distances": []}
+
+        searcher = object.__new__(TestSearcher)
+        searcher.index_path = Path(temp_index_with_template)
+        searcher.index_dir = searcher.index_path.parent
+
+        # Load metadata
+        meta_file = searcher.index_dir / f"{searcher.index_path.name}.meta.json"
+        with open(meta_file) as f:
+            searcher.meta = json.load(f)
+
+        searcher.embedding_model = searcher.meta["embedding_model"]
+        searcher.embedding_mode = searcher.meta.get("embedding_mode", "sentence-transformers")
+        searcher.embedding_options = searcher.meta.get("embedding_options", {})
+
+        # Mock compute_embeddings to capture the query text
+        captured_queries = []
+
+        def mock_compute_embeddings(texts, model, mode, provider_options=None):
+            captured_queries.extend(texts)
+            return np.random.rand(len(texts), 768).astype(np.float32)
+
+        with patch(
+            "leann.embedding_compute.compute_embeddings", side_effect=mock_compute_embeddings
+        ):
+            # Call compute_query_embedding with template (fallback path)
+            result = searcher.compute_query_embedding(
+                query="vector database",
+                use_server_if_available=False,  # Force fallback path
+                query_template="task: search result | query: ",
+            )
+
+        # Verify template was applied
+        assert len(captured_queries) == 1
+        assert captured_queries[0] == "task: search result | query: vector database"
+        assert result.shape == (1, 768)
+
+    def test_query_template_applied_in_server_path(self, temp_index_with_template):
+        """Test that query template is applied when using server path"""
+        from leann.searcher_base import BaseSearcher
+
+        # Create a concrete implementation for testing
+        class TestSearcher(BaseSearcher):
+            def search(self, query_vectors, top_k, complexity, beam_width=1, **kwargs):
+                return {"labels": [], "distances": []}
+
+        searcher = object.__new__(TestSearcher)
+        searcher.index_path = Path(temp_index_with_template)
+        searcher.index_dir = searcher.index_path.parent
+
+        # Load metadata
+        meta_file = searcher.index_dir / f"{searcher.index_path.name}.meta.json"
+        with open(meta_file) as f:
+            searcher.meta = json.load(f)
+
+        searcher.embedding_model = searcher.meta["embedding_model"]
+        searcher.embedding_mode = searcher.meta.get("embedding_mode", "sentence-transformers")
+        searcher.embedding_options = searcher.meta.get("embedding_options", {})
+
+        # Mock the server methods to capture the query text
+        captured_queries = []
+
+        def mock_ensure_server_running(passages_file, port):
+            return port
+
+        def mock_compute_embedding_via_server(chunks, port):
+            captured_queries.extend(chunks)
+            return np.random.rand(len(chunks), 768).astype(np.float32)
+
+        searcher._ensure_server_running = mock_ensure_server_running
+        searcher._compute_embedding_via_server = mock_compute_embedding_via_server
+
+        # Call compute_query_embedding with template (server path)
+        result = searcher.compute_query_embedding(
+            query="vector database",
+            use_server_if_available=True,  # Use server path
+            query_template="task: search result | query: ",
+        )
+
+        # Verify template was applied BEFORE calling server
+        assert len(captured_queries) == 1
+        assert captured_queries[0] == "task: search result | query: vector database"
+        assert result.shape == (1, 768)
+
+    def test_query_template_without_template_parameter(self, temp_index_with_template):
+        """Test that query is unchanged when no template is provided"""
+        from leann.searcher_base import BaseSearcher
+
+        class TestSearcher(BaseSearcher):
+            def search(self, query_vectors, top_k, complexity, beam_width=1, **kwargs):
+                return {"labels": [], "distances": []}
+
+        searcher = object.__new__(TestSearcher)
+        searcher.index_path = Path(temp_index_with_template)
+        searcher.index_dir = searcher.index_path.parent
+
+        meta_file = searcher.index_dir / f"{searcher.index_path.name}.meta.json"
+        with open(meta_file) as f:
+            searcher.meta = json.load(f)
+
+        searcher.embedding_model = searcher.meta["embedding_model"]
+        searcher.embedding_mode = searcher.meta.get("embedding_mode", "sentence-transformers")
+        searcher.embedding_options = searcher.meta.get("embedding_options", {})
+
+        captured_queries = []
+
+        def mock_compute_embeddings(texts, model, mode, provider_options=None):
+            captured_queries.extend(texts)
+            return np.random.rand(len(texts), 768).astype(np.float32)
+
+        with patch(
+            "leann.embedding_compute.compute_embeddings", side_effect=mock_compute_embeddings
+        ):
+            searcher.compute_query_embedding(
+                query="vector database",
+                use_server_if_available=False,
+                query_template=None,  # No template
+            )
+
+        # Verify query is unchanged
+        assert len(captured_queries) == 1
+        assert captured_queries[0] == "vector database"
+
+    def test_query_template_consistency_between_paths(self, temp_index_with_template):
+        """Test that both paths apply template identically"""
+        from leann.searcher_base import BaseSearcher
+
+        class TestSearcher(BaseSearcher):
+            def search(self, query_vectors, top_k, complexity, beam_width=1, **kwargs):
+                return {"labels": [], "distances": []}
+
+        searcher = object.__new__(TestSearcher)
+        searcher.index_path = Path(temp_index_with_template)
+        searcher.index_dir = searcher.index_path.parent
+
+        meta_file = searcher.index_dir / f"{searcher.index_path.name}.meta.json"
+        with open(meta_file) as f:
+            searcher.meta = json.load(f)
+
+        searcher.embedding_model = searcher.meta["embedding_model"]
+        searcher.embedding_mode = searcher.meta.get("embedding_mode", "sentence-transformers")
+        searcher.embedding_options = searcher.meta.get("embedding_options", {})
+
+        query_template = "task: search result | query: "
+        original_query = "vector database"
+
+        # Capture queries from fallback path
+        fallback_queries = []
+
+        def mock_compute_embeddings(texts, model, mode, provider_options=None):
+            fallback_queries.extend(texts)
+            return np.random.rand(len(texts), 768).astype(np.float32)
+
+        with patch(
+            "leann.embedding_compute.compute_embeddings", side_effect=mock_compute_embeddings
+        ):
+            searcher.compute_query_embedding(
+                query=original_query,
+                use_server_if_available=False,
+                query_template=query_template,
+            )
+
+        # Capture queries from server path
+        server_queries = []
+
+        def mock_ensure_server_running(passages_file, port):
+            return port
+
+        def mock_compute_embedding_via_server(chunks, port):
+            server_queries.extend(chunks)
+            return np.random.rand(len(chunks), 768).astype(np.float32)
+
+        searcher._ensure_server_running = mock_ensure_server_running
+        searcher._compute_embedding_via_server = mock_compute_embedding_via_server
+
+        searcher.compute_query_embedding(
+            query=original_query,
+            use_server_if_available=True,
+            query_template=query_template,
+        )
+
+        # Verify both paths produced identical templated queries
+        assert len(fallback_queries) == 1
+        assert len(server_queries) == 1
+        assert fallback_queries[0] == server_queries[0]
+        assert fallback_queries[0] == f"{query_template}{original_query}"
+
+    def test_query_template_with_empty_string(self, temp_index_with_template):
+        """Test behavior with empty template string"""
+        from leann.searcher_base import BaseSearcher
+
+        class TestSearcher(BaseSearcher):
+            def search(self, query_vectors, top_k, complexity, beam_width=1, **kwargs):
+                return {"labels": [], "distances": []}
+
+        searcher = object.__new__(TestSearcher)
+        searcher.index_path = Path(temp_index_with_template)
+        searcher.index_dir = searcher.index_path.parent
+
+        meta_file = searcher.index_dir / f"{searcher.index_path.name}.meta.json"
+        with open(meta_file) as f:
+            searcher.meta = json.load(f)
+
+        searcher.embedding_model = searcher.meta["embedding_model"]
+        searcher.embedding_mode = searcher.meta.get("embedding_mode", "sentence-transformers")
+        searcher.embedding_options = searcher.meta.get("embedding_options", {})
+
+        captured_queries = []
+
+        def mock_compute_embeddings(texts, model, mode, provider_options=None):
+            captured_queries.extend(texts)
+            return np.random.rand(len(texts), 768).astype(np.float32)
+
+        with patch(
+            "leann.embedding_compute.compute_embeddings", side_effect=mock_compute_embeddings
+        ):
+            searcher.compute_query_embedding(
+                query="vector database",
+                use_server_if_available=False,
+                query_template="",  # Empty string
+            )
+
+        # Empty string is falsy, so no template should be applied
+        assert captured_queries[0] == "vector database"

tests/test_token_truncation.py

@@ -266,3 +266,378 @@ class TestTokenTruncation:
         assert result_tokens <= target_tokens, (
             f"Should be ≤{target_tokens} tokens, got {result_tokens}"
         )
+
+
+class TestLMStudioHybridDiscovery:
+    """Tests for LM Studio integration in get_model_token_limit() hybrid discovery.
+
+    These tests verify that get_model_token_limit() properly integrates with
+    the LM Studio SDK bridge for dynamic token limit discovery. The integration
+    should:
+
+    1. Detect LM Studio URLs (port 1234 or 'lmstudio'/'lm.studio' in URL)
+    2. Convert HTTP URLs to WebSocket format for SDK queries
+    3. Query LM Studio SDK and use discovered limit
+    4. Fall back to registry when SDK returns None
+    5. Execute AFTER Ollama detection but BEFORE registry fallback
+
+    All tests are written in Red Phase - they should FAIL initially because the
+    LM Studio detection and integration logic does not exist yet in get_model_token_limit().
+    """
+
+    def test_get_model_token_limit_lmstudio_success(self, monkeypatch):
+        """Verify LM Studio SDK query succeeds and returns detected limit.
+
+        When a LM Studio base_url is detected and the SDK query succeeds,
+        get_model_token_limit() should return the dynamically discovered
+        context length without falling back to the registry.
+        """
+
+        # Mock _query_lmstudio_context_limit to return successful SDK query
+        def mock_query_lmstudio(model_name, base_url):
+            # Verify WebSocket URL was passed (not HTTP)
+            assert base_url.startswith("ws://"), (
+                f"Should convert HTTP to WebSocket format, got: {base_url}"
+            )
+            return 8192  # Successful SDK query
+
+        monkeypatch.setattr(
+            "leann.embedding_compute._query_lmstudio_context_limit",
+            mock_query_lmstudio,
+        )
+
+        # Test with HTTP URL that should be converted to WebSocket
+        limit = get_model_token_limit(
+            model_name="custom-model", base_url="http://localhost:1234/v1"
+        )
+
+        assert limit == 8192, "Should return limit from LM Studio SDK query"
+
+    def test_get_model_token_limit_lmstudio_fallback_to_registry(self, monkeypatch):
+        """Verify fallback to registry when LM Studio SDK returns None.
+
+        When LM Studio SDK query fails (returns None), get_model_token_limit()
+        should fall back to the EMBEDDING_MODEL_LIMITS registry.
+        """
+
+        # Mock _query_lmstudio_context_limit to return None (SDK failure)
+        def mock_query_lmstudio(model_name, base_url):
+            return None  # SDK query failed
+
+        monkeypatch.setattr(
+            "leann.embedding_compute._query_lmstudio_context_limit",
+            mock_query_lmstudio,
+        )
+
+        # Test with known model that exists in registry
+        limit = get_model_token_limit(
+            model_name="nomic-embed-text", base_url="http://localhost:1234/v1"
+        )
+
+        # Should fall back to registry value
+        assert limit == 2048, "Should fall back to registry when SDK returns None"
+
+    def test_get_model_token_limit_lmstudio_port_detection(self, monkeypatch):
+        """Verify detection of LM Studio via port 1234.
+
+        get_model_token_limit() should recognize port 1234 as a LM Studio
+        server and attempt SDK query, regardless of hostname.
+        """
+        query_called = False
+
+        def mock_query_lmstudio(model_name, base_url):
+            nonlocal query_called
+            query_called = True
+            return 4096
+
+        monkeypatch.setattr(
+            "leann.embedding_compute._query_lmstudio_context_limit",
+            mock_query_lmstudio,
+        )
+
+        # Test with port 1234 (default LM Studio port)
+        limit = get_model_token_limit(model_name="test-model", base_url="http://127.0.0.1:1234/v1")
+
+        assert query_called, "Should detect port 1234 and call LM Studio SDK query"
+        assert limit == 4096, "Should return SDK query result"
+
+    @pytest.mark.parametrize(
+        "test_url,expected_limit,keyword",
+        [
+            ("http://lmstudio.local:8080/v1", 16384, "lmstudio"),
+            ("http://api.lm.studio:5000/v1", 32768, "lm.studio"),
+        ],
+    )
+    def test_get_model_token_limit_lmstudio_url_keyword_detection(
+        self, monkeypatch, test_url, expected_limit, keyword
+    ):
+        """Verify detection of LM Studio via keywords in URL.
+
+        get_model_token_limit() should recognize 'lmstudio' or 'lm.studio'
+        in the URL as indicating a LM Studio server.
+        """
+        query_called = False
+
+        def mock_query_lmstudio(model_name, base_url):
+            nonlocal query_called
+            query_called = True
+            return expected_limit
+
+        monkeypatch.setattr(
+            "leann.embedding_compute._query_lmstudio_context_limit",
+            mock_query_lmstudio,
+        )
+
+        limit = get_model_token_limit(model_name="test-model", base_url=test_url)
+
+        assert query_called, f"Should detect '{keyword}' keyword and call SDK query"
+        assert limit == expected_limit, f"Should return SDK query result for {keyword}"
+
+    @pytest.mark.parametrize(
+        "input_url,expected_protocol,expected_host",
+        [
+            ("http://localhost:1234/v1", "ws://", "localhost:1234"),
+            ("https://lmstudio.example.com:1234/v1", "wss://", "lmstudio.example.com:1234"),
+        ],
+    )
+    def test_get_model_token_limit_protocol_conversion(
+        self, monkeypatch, input_url, expected_protocol, expected_host
+    ):
+        """Verify HTTP/HTTPS URL is converted to WebSocket format for SDK query.
+
+        LM Studio SDK requires WebSocket URLs. get_model_token_limit() should:
+        1. Convert 'http://' to 'ws://'
+        2. Convert 'https://' to 'wss://'
+        3. Remove '/v1' or other path suffixes (SDK expects base URL)
+        4. Preserve host and port
+        """
+        conversions_tested = []
+
+        def mock_query_lmstudio(model_name, base_url):
+            conversions_tested.append(base_url)
+            return 8192
+
+        monkeypatch.setattr(
+            "leann.embedding_compute._query_lmstudio_context_limit",
+            mock_query_lmstudio,
+        )
+
+        get_model_token_limit(model_name="test-model", base_url=input_url)
+
+        # Verify conversion happened
+        assert len(conversions_tested) == 1, "Should have called SDK query once"
+        assert conversions_tested[0].startswith(expected_protocol), (
+            f"Should convert to {expected_protocol}"
+        )
+        assert expected_host in conversions_tested[0], (
+            f"Should preserve host and port: {expected_host}"
+        )
+
+    def test_get_model_token_limit_lmstudio_executes_after_ollama(self, monkeypatch):
+        """Verify LM Studio detection happens AFTER Ollama detection.
+
+        The hybrid discovery order should be:
+        1. Ollama dynamic discovery (port 11434 or 'ollama' in URL)
+        2. LM Studio dynamic discovery (port 1234 or 'lmstudio' in URL)
+        3. Registry fallback
+
+        If both Ollama and LM Studio patterns match, Ollama should take precedence.
+        This test verifies that LM Studio is checked but doesn't interfere with Ollama.
+        """
+        ollama_called = False
+        lmstudio_called = False
+
+        def mock_query_ollama(model_name, base_url):
+            nonlocal ollama_called
+            ollama_called = True
+            return 2048  # Ollama query succeeds
+
+        def mock_query_lmstudio(model_name, base_url):
+            nonlocal lmstudio_called
+            lmstudio_called = True
+            return None  # Should not be reached if Ollama succeeds
+
+        monkeypatch.setattr(
+            "leann.embedding_compute._query_ollama_context_limit",
+            mock_query_ollama,
+        )
+        monkeypatch.setattr(
+            "leann.embedding_compute._query_lmstudio_context_limit",
+            mock_query_lmstudio,
+        )
+
+        # Test with Ollama URL
+        limit = get_model_token_limit(
+            model_name="test-model", base_url="http://localhost:11434/api"
+        )
+
+        assert ollama_called, "Should attempt Ollama query first"
+        assert not lmstudio_called, "Should not attempt LM Studio query when Ollama succeeds"
+        assert limit == 2048, "Should return Ollama result"
+
+    def test_get_model_token_limit_lmstudio_not_detected_for_non_lmstudio_urls(self, monkeypatch):
+        """Verify LM Studio SDK query is NOT called for non-LM Studio URLs.
+
+        Only URLs with port 1234 or 'lmstudio'/'lm.studio' keywords should
+        trigger LM Studio SDK queries. Other URLs should skip to registry fallback.
+        """
+        lmstudio_called = False
+
+        def mock_query_lmstudio(model_name, base_url):
+            nonlocal lmstudio_called
+            lmstudio_called = True
+            return 8192
+
+        monkeypatch.setattr(
+            "leann.embedding_compute._query_lmstudio_context_limit",
+            mock_query_lmstudio,
+        )
+
+        # Test with non-LM Studio URLs
+        test_cases = [
+            "http://localhost:8080/v1",  # Different port
+            "http://openai.example.com/v1",  # Different service
+            "http://localhost:3000/v1",  # Another port
+        ]
+
+        for base_url in test_cases:
+            lmstudio_called = False  # Reset for each test
+            get_model_token_limit(model_name="nomic-embed-text", base_url=base_url)
+            assert not lmstudio_called, f"Should NOT call LM Studio SDK for URL: {base_url}"
+
+    def test_get_model_token_limit_lmstudio_case_insensitive_detection(self, monkeypatch):
+        """Verify LM Studio detection is case-insensitive for keywords.
+
+        Keywords 'lmstudio' and 'lm.studio' should be detected regardless
+        of case (LMStudio, LMSTUDIO, LmStudio, etc.).
+        """
+        query_called = False
+
+        def mock_query_lmstudio(model_name, base_url):
+            nonlocal query_called
+            query_called = True
+            return 8192
+
+        monkeypatch.setattr(
+            "leann.embedding_compute._query_lmstudio_context_limit",
+            mock_query_lmstudio,
+        )
+
+        # Test various case variations
+        test_cases = [
+            "http://LMStudio.local:8080/v1",
+            "http://LMSTUDIO.example.com/v1",
+            "http://LmStudio.local/v1",
+            "http://api.LM.STUDIO:5000/v1",
+        ]
+
+        for base_url in test_cases:
+            query_called = False  # Reset for each test
+            limit = get_model_token_limit(model_name="test-model", base_url=base_url)
+            assert query_called, f"Should detect LM Studio in URL: {base_url}"
+            assert limit == 8192, f"Should return SDK result for URL: {base_url}"
+
+
+class TestTokenLimitCaching:
+    """Tests for token limit caching to prevent repeated SDK/API calls.
+
+    Caching prevents duplicate SDK/API calls within the same Python process,
+    which is important because:
+    1. LM Studio SDK load() can load duplicate model instances
+    2. Ollama /api/show queries add latency
+    3. Registry lookups are pure overhead
+
+    Cache is process-scoped and resets between leann build invocations.
+    """
+
+    def setup_method(self):
+        """Clear cache before each test."""
+        from leann.embedding_compute import _token_limit_cache
+
+        _token_limit_cache.clear()
+
+    def test_registry_lookup_is_cached(self):
+        """Verify that registry lookups are cached."""
+        from leann.embedding_compute import _token_limit_cache
+
+        # First call
+        limit1 = get_model_token_limit("text-embedding-3-small")
+        assert limit1 == 8192
+
+        # Verify it's in cache
+        cache_key = ("text-embedding-3-small", "")
+        assert cache_key in _token_limit_cache
+        assert _token_limit_cache[cache_key] == 8192
+
+        # Second call should use cache
+        limit2 = get_model_token_limit("text-embedding-3-small")
+        assert limit2 == 8192
+
+    def test_default_fallback_is_cached(self):
+        """Verify that default fallbacks are cached."""
+        from leann.embedding_compute import _token_limit_cache
+
+        # First call with unknown model
+        limit1 = get_model_token_limit("unknown-model-xyz", default=512)
+        assert limit1 == 512
+
+        # Verify it's in cache
+        cache_key = ("unknown-model-xyz", "")
+        assert cache_key in _token_limit_cache
+        assert _token_limit_cache[cache_key] == 512
+
+        # Second call should use cache
+        limit2 = get_model_token_limit("unknown-model-xyz", default=512)
+        assert limit2 == 512
+
+    def test_different_urls_create_separate_cache_entries(self):
+        """Verify that different base_urls create separate cache entries."""
+        from leann.embedding_compute import _token_limit_cache
+
+        # Same model, different URLs
+        limit1 = get_model_token_limit("nomic-embed-text", base_url="http://localhost:11434")
+        limit2 = get_model_token_limit("nomic-embed-text", base_url="http://localhost:1234/v1")
+
+        # Both should find the model in registry (2048)
+        assert limit1 == 2048
+        assert limit2 == 2048
+
+        # But they should be separate cache entries
+        cache_key1 = ("nomic-embed-text", "http://localhost:11434")
+        cache_key2 = ("nomic-embed-text", "http://localhost:1234/v1")
+
+        assert cache_key1 in _token_limit_cache
+        assert cache_key2 in _token_limit_cache
+        assert len(_token_limit_cache) == 2
+
+    def test_cache_prevents_repeated_lookups(self):
+        """Verify that cache prevents repeated registry/API lookups."""
+        from leann.embedding_compute import _token_limit_cache
+
+        model_name = "text-embedding-ada-002"
+
+        # First call - should add to cache
+        assert len(_token_limit_cache) == 0
+        limit1 = get_model_token_limit(model_name)
+
+        cache_size_after_first = len(_token_limit_cache)
+        assert cache_size_after_first == 1
+
+        # Multiple subsequent calls - cache size should not change
+        for _ in range(5):
+            limit = get_model_token_limit(model_name)
+            assert limit == limit1
+            assert len(_token_limit_cache) == cache_size_after_first
+
+    def test_versioned_model_names_cached_correctly(self):
+        """Verify that versioned model names (e.g., model:tag) are cached."""
+        from leann.embedding_compute import _token_limit_cache
+
+        # Model with version tag
+        limit = get_model_token_limit("nomic-embed-text:latest", base_url="http://localhost:11434")
+        assert limit == 2048
+
+        # Should be cached with full name including version
+        cache_key = ("nomic-embed-text:latest", "http://localhost:11434")
+        assert cache_key in _token_limit_cache
+        assert _token_limit_cache[cache_key] == 2048