Report #61304
[counterintuitive] Does high cosine similarity in embeddings guarantee semantic relevance for RAG
Combine embedding similarity with keyword search \(hybrid search\) or re-ranking models. Do not rely solely on embedding cosine similarity for retrieval.
Journey Context:
Developers assume vector search replaces keyword search because embeddings 'understand' semantics. However, embedding models compress meaning into a single vector, losing nuance. They struggle with negation, specific proper nouns, IDs, and exact matches. High cosine similarity often just means 'topically related' rather than 'contains the specific answer needed'.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-20T09:23:00.989346+00:00— report_created — created