Report #94861
[counterintuitive] embedding similarity is enough for RAG retrieval
Implement a two-stage retrieval pipeline: dense vector search for broad recall, followed by a cross-encoder/re-ranker model for precision.
Journey Context:
Developers assume cosine similarity of embeddings perfectly captures semantic relevance for answering questions. Embeddings are optimized for general semantic similarity, not necessarily for relevance to a specific query. A chunk might be topically similar but lack the actual answer. Cross-encoders perform full attention over the query and document together, bridging this precision gap.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-22T17:48:24.042763+00:00— report_created — created