PR Review Summary

Status: Approved

🪜 Strategic-Fit Decision

Per §9 Strategic-Fit Step-Back:

• Decision: Approve
• Rationale: The PR keeps the #10129 atomic-bundle backup model intact while replacing the hardcoded bundle-retention constants with an operator-configurable two-axis policy. The important architectural choice is the scope reduction from the ticket's initial KB+MC fallback idea to mcConfig.backupRetention only: backup path and orchestration are MC-owned today, so keeping this as a single MC config surface is cleaner than scattering the same policy across KB config for discoverability. Defaults preserve the pre-#11663 K=3, N_DAYS=30 behavior, and the new direct tests plus existing backup regression tests cover the affected retention primitive.

Peer-Review Opening: Solid Phase 4 slice. The implementation resists per-substrate-retention scope creep and keeps the bundle as the retention unit, which is the right constraint until Phase 2/operational cadence data exists.

🕸️ Context & Graph Linking

• Target Epic / Issue ID: Resolves #11663
• Related Graph Nodes: Phase 4 Epic #11628; Meta-Epic #11624; atomic-bundle origin #10129; sibling nightshift lanes #11631 / PR #11662 and #11661.

🔬 Depth Floor

Challenge OR documented search (per guide §7.1):

• Challenge: backupRetention is trusted operator config and currently has no defensive normalization for malformed values such as negative keepMinimum, non-number strings, or negative maxDays. I do not consider this blocking because the shipped template documents numeric defaults, the defaults preserve prior behavior, and the ticket scope is config-driven retention rather than config validation. It is worth tracking if we later expose retention settings through a generated UI, remote config, or any non-operator-controlled source.

Rhetorical-Drift Audit (per guide §7.4):

• PR description: framing matches the diff; this parameterizes bundle-level retention and explicitly defers per-substrate retention asymmetry.
• Anchor & Echo summaries: JSDoc and comments stay tied to keepMinimum, maxDays, and atomic bundle behavior.
• [RETROSPECTIVE] tag: N/A — no retrospective tag in the PR body.
• Linked anchors: #11628, #11624, #10129, and #11663 are the correct lineage for this Phase 4 retention surface.

Findings: Pass.

🧠 Graph Ingestion Notes

• [KB_GAP]: N/A.
• [TOOLING_GAP]: The first sandboxed gh pr checks 11664 call returned error connecting to api.github.com; the escalated read-only rerun succeeded and all checks passed.
• [RETROSPECTIVE]: Bundle-level retention parameterization is the right intermediate shape for Phase 4: it gives operators control over disk/cadence/recovery tradeoffs without breaking the atomic backup bundle into partial-retention substrates.

🛂 Provenance Audit

• Internal Origin: #11663 from Phase 4 #11628 / meta-epic #11624, grounded in the existing backup bundle architecture from #10129 and the 2026-05-17 Memory Core recovery pressure.

Findings: Pass.

🎯 Close-Target Audit

• Close-targets identified: Resolves #11663
• For #11663: verified labels are enhancement, ai; no epic label.
• Commit body repeats (#11663) but does not introduce a stale epic close-target.

Findings: Pass.

📑 Contract Completeness Audit

• The originating ticket defines the intended config contract through acceptance criteria rather than a formal Contract Ledger matrix.
• Implemented PR diff intentionally narrows the ticket's KB+MC config proposal to MC-only config ownership; the PR body's Deltas from ticket section explicitly documents the change and the technical reason.
• The shipped config surface is backupRetention: {keepMinimum: 3, maxDays: 30} in ai/mcp/server/memory-core/config.template.mjs, consumed by buildScripts/ai/backup.mjs through mcConfig.backupRetention with function-default fallback.

Findings: Pass — the live implementation and PR body define a coherent MC-owned contract. No RA needed for the older KB+MC ticket sketch.

🪜 Evidence Audit

The PR body declares Evidence: L2 (8 new unit tests covering default byte-equivalence anchor + tighter / higher-cadence / missing-config / empty-config / extreme-zero scenarios; existing 7 backup.spec tests pass as regression) → L2 required (retention policy is mechanically verifiable in unit-test scope; no runtime-only surfaces). No residuals.

• Evidence declaration line present.
• Achieved L2 matches the close-target requirement: retention behavior is mechanically testable at unit scope.
• No residuals claimed; post-merge smoke items are operator validation for live config/history, not missing acceptance coverage.
• No evidence-class collapse: review and PR body keep this at L2, not runtime smoke or live deployment proof.

Findings: Pass.

📜 Source-of-Authority Audit

N/A — this review does not cite operator or peer authority as the basis for a demand. The approval is based on diff, ticket, local tests, and CI state.

📡 MCP-Tool-Description Budget Audit

N/A — no ai/mcp/server/*/openapi.yaml tool descriptions changed.

🔌 Wire-Format Compatibility Audit

N/A — no JSON-RPC, A2A, MCP tool, or persisted record wire format changed. This is a local config-template and backup-script behavior change.

🔗 Cross-Skill Integration Audit

• ai/mcp/server/memory-core/config.template.mjs changed; the PR body includes config-template clone-sync guidance.
• Changed key is listed explicitly: backupRetention: {keepMinimum: 3, maxDays: 30}.
• Local config.mjs behavior is documented: zero-config deployments need no action; cloud/tighter-budget deployments can add overrides; restart/read timing is described.
• No skill files, AGENTS_STARTUP.md, or MCP tool surfaces require updates for this implementation.

Findings: Pass.

🧪 Test-Execution & Location Audit

• Branch checked out locally: agent/11663-backup-retention-config at 34fc6287706f3e275d66a7342206082f9267e4cd.
• Canonical Location: new spec is under test/playwright/unit/ai/buildScripts/backup-retention.spec.mjs, matching the existing backup-script unit-test location.
• Ran npm run test-unit -- test/playwright/unit/ai/buildScripts/backup-retention.spec.mjs test/playwright/unit/ai/buildScripts/backup.spec.mjs -> 15 passed (710ms).
• Code changed and has direct coverage: 8 new retention tests plus 7 existing backup regression tests.

Findings: Tests pass; location is canonical.

🛡️ CI / Security Checks Audit

• Ran gh pr checks 11664 after the sandboxed call hit a transient API connection error.
• All checks pass: Analyze (javascript), CodeQL, check, integration-unified, lint-pr-body, unit.
• No checks pending or failing.

Findings: Pass - all checks green.

📏 Measurement Payload

Static surface:
- pr-review-guide.md: 58968 bytes
- pr-review-template.md: 13561 bytes
- ci-security-audit.md: 2348 bytes
- measurement-methodology.md: 3225 bytes
Static total: 78102 bytes
Dynamic surface used in-review: PR body/commits/closingRefs + #11663 issue body + files-only diff + local test output + gh checks output.

📋 Required Actions

No required actions — eligible for human merge.

Optional follow-up, not merge-blocking:

• Add explicit validation/normalization for malformed retention config values if backupRetention is later exposed beyond operator-owned local config.mjs.

📊 Evaluation Metrics

• [ARCH_ALIGNMENT]: 95 — 5 points deducted because the ticket-to-implementation contract needed a documented scope correction from KB+MC fallback to MC-only ownership; the correction is architecturally better, but future readers must notice the PR body's delta note.
• [CONTENT_COMPLETENESS]: 95 — 5 points deducted because the originating ticket uses acceptance criteria rather than a formal Contract Ledger for this new config surface. PR body, JSDoc, config-template docs, and test comments are otherwise complete and precise.
• [EXECUTION_QUALITY]: 95 — 5 points deducted for the non-blocking absence of malformed config normalization. Direct behavior, defaults, edge cases, and regression coverage all pass locally and in CI.
• [PRODUCTIVITY]: 100 — I actively considered ticket AC drift, default behavior preservation, per-substrate retention scope creep, local config clone-sync, and test placement, and confirmed none block this PR.
• [IMPACT]: 80 — Major operational substrate improvement: operators can tune backup retention for cloud disk budgets, high cadence, and recovery windows without forking backup.mjs, while preserving the existing default safety floor.
• [COMPLEXITY]: 45 — Moderate-low: one config-template key, one exported retention function argument, one call-site change, and focused tests. The cognitive load is mostly policy semantics rather than broad code churn.
• [EFFORT_PROFILE]: Quick Win — High operational ROI with small, well-contained implementation and strong unit-test coverage.

Eligible for @tobiu's human merge gate.