These are the real retrieval-quality numbers: the production hybrid pipeline (semantic pgvector leg + BM25 keyword leg -> RRF k=60 -> cross-encoder rerank) run with a learned local
sentence-transformersembedder over a real, heterogeneous corpus (the Forge monorepo). They supersede an earlier deterministic wiring-check baseline — an offline embedder + fixture reranker over small golden sets, whoserecall@5 = 1.000proved only that the pipeline was wired, not its real-world quality.
- Date: 2026-07-04
- Embedder: local (sentence-transformers/all-MiniLM-L6-v2, 384-dim, no key)
- Reranker: fixture (deterministic token-overlap stand-in; learned Jina delta is BYOK/AC9)
- Corpus files: 983
- Corpus commit:
95228d6 - Golden cases: 36
- k (recall/MRR): 5 · nDCG cutoff: 10
The complete pipeline: semantic + keyword -> RRF k=60 -> reranker -> top-k. On the no-creds BETA path the reranker is the deterministic fixture stand-in (a weak token-overlap placeholder for the creds-gated learned Jina cross-encoder — see the reranker delta below).
| metric | value |
|---|---|
| recall@5 | 0.778 |
| recall@10 | 0.861 |
| MRR | 0.631 |
| nDCG@10 | 0.686 |
| hit_rate@5 | 0.778 |
| cases passed | 28/36 |
Honesty check: mean recall@5 = 0.778 is in a realistic band 0 < x < 1 (not perfect by construction). The misses are genuine (a class definition outranked by its tests / consumers / spec docs), exactly the hard cases the eval exists to surface.
hybrid here is the RRF-fused ranking (no reranker), isolating the fusion claim (F05 AC4) from the reranker stage.
| leg | recall@k | MRR | nDCG | hit_rate |
|---|---|---|---|---|
| hybrid (RRF fusion) | 0.847 | 0.695 | 0.750 | 0.861 |
| vector_only | 0.792 | 0.629 | 0.688 | 0.806 |
| keyword_only | 0.806 | 0.529 | 0.611 | 0.806 |
Fused recall - best single leg = +0.042 (hybrid >= each leg: fusion adds recall).
- RRF fusion (no rerank): recall@5 = 0.847
-
- fixture reranker (BETA stand-in): recall@5 = 0.778 → delta -0.069
- The fixture reranker is a deterministic token-overlap placeholder; on short/identifier queries it can demote good fused results (a negative delta is expected). The learned Jina/Cohere cross-encoder delta is the creds-gated measurement (AC9): set
FORGE_EVAL_RERANKER=jinawith a BYOK key in.env.integration— PARKED until creds exist.
FORGE_EVAL_RECALL_FLOOR= 0.700 (recall@5 floor)FORGE_EVAL_NDCG_FLOOR= 0.600 (nDCG@10 floor)- Current run vs floors: PASS
An earlier concern held that the deterministic eval's 1.000 scores did not prove real retrieval quality — a realism gap, not a code defect in forge_knowledge.sync or forge_eval.retrieval_eval. This real-corpus run with a learned embedder closes that gap. The sync ingestion path is unchanged and remains green; no code defect was surfaced. See the note in forge_eval/retrieval_eval.py.
Golden retrieval eval — 36 case(s), k=5
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case recall@5 MRR nDCG@10 hit
real-001 1.000 0.500 0.631 Y ok
real-002 1.000 1.000 1.000 Y ok
real-003 1.000 1.000 1.000 Y ok
real-004 1.000 0.333 0.500 Y ok
real-005 0.000 0.000 0.000 N X
real-006 1.000 1.000 1.000 Y ok
real-007 1.000 1.000 1.000 Y ok
real-008 1.000 1.000 1.000 Y ok
real-009 1.000 0.500 0.631 Y ok
real-010 1.000 1.000 1.000 Y ok
real-011 0.000 0.000 0.000 N X
real-012 1.000 1.000 1.000 Y ok
real-013 1.000 1.000 1.000 Y ok
real-014 1.000 0.500 0.631 Y ok
real-015 1.000 1.000 1.000 Y ok
real-016 1.000 1.000 1.000 Y ok
real-017 0.000 0.000 0.000 N X
real-018 1.000 1.000 0.950 Y ok
real-019 1.000 1.000 1.000 Y ok
real-020 1.000 1.000 1.000 Y ok
real-021 0.000 0.000 0.000 N X
real-022 1.000 0.250 0.431 Y ok
real-023 1.000 1.000 1.000 Y ok
real-024 0.000 0.111 0.301 N X
real-025 0.000 0.143 0.333 N X
real-026 1.000 1.000 1.000 Y ok
real-027 1.000 1.000 1.000 Y ok
real-028 1.000 0.500 0.631 Y ok
real-029 0.000 0.143 0.333 N X
real-030 1.000 0.500 0.631 Y ok
real-031 1.000 1.000 1.000 Y ok
real-032 1.000 0.250 0.431 Y ok
real-033 1.000 0.500 0.631 Y ok
real-034 1.000 1.000 1.000 Y ok
real-035 1.000 0.500 0.631 Y ok
real-036 0.000 0.000 0.000 N X
------------------------------------------------------------------------
mean recall@5=0.778 MRR=0.631 nDCG@10=0.686 hit_rate=0.778 passed=28/36
gate (recall@5 >= 0.700, nDCG@10 >= 0.600): PASS
Ablation — hybrid vs single-leg (same corpus + golden set)
------------------------------------------------------------------------
leg recall@k MRR nDCG hit_rate
hybrid 0.847 0.695 0.750 0.861
vector_only 0.792 0.629 0.688 0.806
keyword_only 0.806 0.529 0.611 0.806
------------------------------------------------------------------------
hybrid recall - best single leg = +0.042 (fusion adds recall: PASS)