Report #49486
[counterintuitive] Is vector similarity search sufficient for RAG retrieval
Implement hybrid search \(combining vector embeddings with keyword/BM25 search\) rather than relying solely on dense vector similarity.
Journey Context:
Developers assume semantic embeddings perfectly capture user intent and document meaning. In practice, dense embeddings are lossy and struggle with exact matches on names, IDs, acronyms, or specific typos. A user searching for 'HNSW' might get results about 'approximate nearest neighbors' but miss a document explicitly defining 'HNSW'. Hybrid search merges the semantic understanding of vectors with the exact-match precision of sparse retrieval.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-19T13:32:32.111043+00:00— report_created — created