PR Review Summary

Status: Approved

🪜 Strategic-Fit Decision

Per §9 Strategic-Fit Step-Back:

• Decision: Approve
• Rationale: Fully implements the #12715 perf-harden I filed — a build-once cached source index replaces the per-query ~1,500-file scan — and addresses every AC I specified (including the no-anchor negative test), plus a bonus type-gate. Empirically verified: 10/10 QueryService specs on my checkout. No blocking defects.

Peer-Review Opening: This closes the loop cleanly — I flagged the I/O cost on #12710, filed #12715, and this implements it exactly (and added the no-anchor negative test I'd asked for). Verified empirically (checkout + 10/10 specs), not from the diff.

🧭 Patch-Blind Premise Snapshot

• Inputs Read Before Patch: #12715 (the perf-harden ACs I filed), the original addCodeTermRescues from #12710, the diff, and the empirical checkout.
• Expected Solution Shape: a build-once cache/index replacing the per-query scan, preserving the #12703 rescue + tenant-stamping, plus a no-anchor negative test and a clear/refresh hook-point.
• Patch Verdict: Matches + exceeds. getCodeTermRescueIndex (build-once, promise-guarded against concurrent double-build) + a type-gate (scope-narrow to {all,src,raw}) + clearCodeTermRescueIndex (the refresh hook-point) + all ACs + 10/10 empirical.

🕸️ Context & Graph Linking

• Target Epic / Issue ID: Resolves #12715
• Related Graph Nodes: #12710 (introduced addCodeTermRescues), #12703 (the regression), #12696 (epic)

🔬 Depth Floor

Challenge (non-blocking): The cache is build-once-per-service-lifetime, with clearCodeTermRescueIndex() whose JSDoc names "future content-refresh hooks" — but that clear isn't yet WIRED to a runtime content-change trigger (only tests call it). So a long-lived KB server's index could drift from on-disk content (a new/edited file wouldn't be rescued until a restart/clear). gpt acknowledges this in-doc, and for fairly-static repo content it's a reasonable trade now — flagging as a forward note (wire the clear into the content-sync/refresh path when that lands), not a gate.

Rhetorical-Drift Audit (per guide §7.4): the JSDoc accurately describes the cache (build-once; the staleness-vs-restart trade is acknowledged, not overstated). Pass.

🧪 Test-Execution & Location Audit

• Branch checked out (gh pr checkout 12718) — §2.2 empirical pass, not a static read.
• Ran the related spec: npm run test-unit -- .../QueryService.queryDocuments.spec.mjs → 10 passed (859ms): the 6 baseline + (#12715) no-anchor-no-build (test 7), non-code-typed-no-build (8), index-reused-across-queries (9), + (#12703) rescue-still-works (10).
• Canonical location: tests in test/playwright/unit/ai/services/knowledge-base/ ✓.
• Findings: 10/10 pass (independently verified). My #12715 ACs all met (cache/no-per-query-scan ✓, #12703-preserved ✓, no-anchor negative test ✓, clear-hook ✓); tenant-stamping unchanged (downstream of the index).

🎯 Close-Target Audit

• Resolves #12715 (the perf-ticket I filed; labels ai, enhancement, performance — NOT epic). Commit body clean (close-keyword in subject only). Valid.
• Findings: Pass.

N/A Audits — 📑 📡 🔗

N/A: the cache is internal to QueryService (no public API/config-consumer contract change), no MCP/wire surface, no new cross-substrate convention.

📋 Required Actions

No required actions — eligible for human merge. The cache-staleness / unwired-clear-hook is an optional forward note (wire the clear into the content-refresh path when it lands), not a gate.

📊 Evaluation Metrics

• [ARCH_ALIGNMENT]: 100 — clean caching shape (build-once + promise-guard against concurrent double-build + a clear method); the type-gate is a sound scope-narrow; preserves the rescue + tenant-stamping. Confirmed no concurrent-build race, no #12703 regression, no tenant change.
• [CONTENT_COMPLETENESS]: 100 — JSDoc (@summary/@param/@returns) on all new methods; the staleness/refresh trade acknowledged in-doc; lint-pr-body green; all #12715 ACs addressed.
• [EXECUTION_QUALITY]: 95 — 10/10 specs on my checkout, no defects; 5 deducted for the cache-staleness (the clear-hook isn't wired to a content-change trigger yet — a long-lived server could drift until restart).
• [PRODUCTIVITY]: 100 — fully resolves #12715 (every AC + the bonus type-gate).
• [IMPACT]: 70 — perf-harden of the default KB tool's retrieval (kills the per-query ~1,500-file scan); meaningful hardening.
• [COMPLEXITY]: 45 — moderate: the cache lifecycle (build-once, promise-guard, clear) + the type-gate + 3 new tests; clean but introduces caching-staleness reasoning.
• [EFFORT_PROFILE]: Quick Win — focused change, high ROI (eliminates the scan).

Clean close to the loop — flagged → filed → implemented → verified. The no-anchor negative test landing exactly as specced is the chef's-kiss. Approving.