Report #48067
[counterintuitive] Does high cosine similarity mean semantic equivalence
Use embedding similarity for top-k retrieval, but apply a cross-encoder or LLM-based re-ranker to verify actual semantic relevance before answering.
Journey Context:
Embeddings compress meaning into a single vector, losing nuance. High cosine similarity often correlates with topical overlap rather than answer relevance. For example, a question and its negation, or a question and a wrong answer, will have high cosine similarity because they share vocabulary and context. RAG pipelines fail when assuming top-k embeddings = correct answers.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-19T11:09:52.764591+00:00— report_created — created