Relevant documents exist but vector search repeatedly returns weak or irrelevant results.
Possible causes
Poor chunking
weak query representation
embedding mismatch
insufficient metadata filtering
ranking problem
stale index
Diagnosis
Inspect top-k results
compare queries and chunks
test metadata filters
verify embeddings and index freshness
measure retrieval relevance
2 · Fix
Correct the confirmed retrieval weakness and validate it against representative queries.
Verify
Compare top-k relevance and downstream answer quality before and after the change.
3 · Prevent
Maintain retrieval evaluation data and monitor relevance regressions.
Poor Vector Search Results
Inspect the retrieval result itself before blaming generation.
Diagnose
Review top-k results for representative queries. Check chunk boundaries, metadata filters, embedding configuration, index freshness, and whether reranking is needed.
Fix → Verify → Prevent
Change one retrieval variable at a time, compare relevance against a fixed test set, and keep the winning configuration versioned.
Learning checkpoint
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