# Decisions: rag-eval-hybrid-baseline（最终版）

## Process

sm-flow standard-lean: Discover → Commit → Apply → Archive.

## Key decisions

1. Replace eval generator `vector-store.mode` with `retrieval.search.mode` (default hybrid).
2. Fixture meta: `searchMode`, `kbScope` when set.
3. Knife-2 (dual fixtures / mustNot golden) deferred.
4. Live refresh succeeded in apply env; baseline updated to hybrid snapshots.
5. **Quality gate refinement (apply-found):** hybrid absolute quality for `isLowQuality` / relevance uses optional dense L2 (`denseDistance`); does not overwrite hybrid scoreLabel or RRF order. Rank mapping remains fallback when dense missing.

## Trade-offs

- Extra dense ANN on hybrid path for gate calibration (latency) vs correct filter-fallback behavior.
- relevance_level still not a hard golden assertion (ordinal vs absolute mix).