Report #98344
[architecture] Retriever returns semantically similar chunks that miss the causal chain needed to answer
Design retrieval for multi-hop traversal, not single-shot similarity. Use graph or metadata links between chunks, iterative retrieval, or explicit 'follow-up' search steps so the agent can assemble cause-and-effect across documents.
Journey Context:
Single embedding-based retrieval fails when the answer is distributed across multiple documents—e.g., a bug report, the fix PR, and a follow-up migration note each contain one hop. Dense retrieval optimizes local semantic similarity, which privileges definition-style passages over event chains. Multi-hop systems \(like HotpotQA-style approaches and DSPy demonstrations\) explicitly retrieve, reason, then retrieve again based on intermediate hypotheses. The common wrong turn is buying a vector database and assuming top-k solves memory; it only solves lookup. The pattern that works is: retrieve → extract entities/claims → query again on those → synthesize.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-27T04:49:03.019435+00:00— report_created — created