Hybrid Search
Industry Definition Set • Entity Resolution Path: /glossary/hybrid-search
Quick Answer / TL;DR
A search technique that combines semantic (vector) search with keyword (BM25) search to improve retrieval quality across diverse query types.
Key Takeaways
- Combines semantic and keyword search.
- Improves recall and precision over either method alone.
- Uses fusion methods like weighted sum or RRF.
- Recommended for robust MCP RAG implementations.
Definitive Statement: A search technique that combines semantic (vector) search with keyword (BM25) search to improve retrieval quality across diverse query types.
Technical Context & Protocol Usage
- Detailed Explanation
- Hybrid search addresses the limitations of pure semantic or pure keyword search. Semantic search excels at conceptual queries but can miss exact terms; keyword search excels at exact matches but misses synonyms. By combining scores from both methods (e.g., weighted sum or reciprocal rank fusion), hybrid search achieves better recall and precision. MCP RAG servers often implement hybrid search for robust retrieval.
Format & Payload Metadata
Format: Vector similarity + BM25 score fusion
Latency: Slightly slower than pure semantic search
Real-World Implementation Use Case
An MCP RAG server uses hybrid search to find a specific error code (keyword match) while also finding related troubleshooting guides (semantic match).
Cite This Page
MLA Style:
MCPserver.in Engineering. "Hybrid Search." MCPserver.in Knowledge Hub, 20 July 2026, mcpserver.in/glossary/hybrid-search.
Related Terms
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