Meta-layer over Phase 19 playbook_memory. Phase 19 answers "which
WORKERS worked for this event"; KB answers "which CONFIG worked for
this playbook signature" — model choice, budget hints, pathway notes,
error corrections.
tests/multi-agent/kb.ts:
- computeSignature(): stable sha256 hash of the (kind, role, count,
city, state) tuple sequence. Same scenario shape → same sig.
- indexRun(): extracts sig, embeds spec digest via sidecar, appends
outcome record, upserts signature to data/_kb/signatures.jsonl.
- findNeighbors(): cosine-ranks the k most-similar signatures from
prior runs for a target spec.
- detectErrorCorrections(): scans outcomes for same-sig fail→succeed
pairs, diffs the model set, logs to error_corrections.jsonl.
- recommendFor(): feeds target digest + k-NN neighbors + recent
corrections to the overview model, gets back a structured JSON
recommendation (top_models, budget_hints, pathway_notes), appends
to pathway_recommendations.jsonl. JSON-shape constrained so the
executor can inherit it mechanically.
- loadRecommendation(): at scenario start, pulls newest rec matching
this sig (or nearest).
scenario.ts:
- Reads KB recommendation at startup (alongside prior lessons).
- Injects pathway_notes into guidanceFor() executor context.
- After retrospective, indexes the run + synthesizes next rec.
Cold-start behavior: first run with no history writes a low-confidence
"no prior data" rec so the signal that something was attempted is
captured. Second run gets "low confidence, 0 neighbors" until a third
distinct sig gives the embedder something to compare against — hence
the upcoming scenario generator.
VERIFIED:
- data/_kb/ populated after one scenario run: 1 outcome (sig=4674…,
4/5 ok, 16 turns total), 1 signature, 2 recs (cold + post-run).
- Recommendation JSON-parsed cleanly from gpt-oss:20b overview model.
PRD Phase 22 added with file layout, cycle description, and the
rationale for file-based MVP → Rust port progression that matches
how Phase 21 primitives shipped.
What's NOT here yet (batched follow-ups per J's request, tested
between each):
- Lift the k=10 hybrid_search cap to adaptive k=max(count*5, 20)
- Scenario generator to bulk-populate KB with varied signatures
- Rust re-weighting: push playbook_memory success signal INTO
hybrid_search scoring, not just post-hoc boost
