PR Review Summary

Status: Approved

Strategic-Fit Decision

Per §9 Strategic-Fit Step-Back:

• Decision: Approve
• Rationale: This is genuine Sub-1 substrate — source-anchored hypothesis matrix + per-hypothesis forensic protocols + typed Sub-3 cycle contract + Sub-9 test mapping + operator deceptive-signal warnings. No runtime mutation; pure documentation that unblocks #12068/#12069/#12075 implementers and gives operator-facing diagnostic protocol for live Sandman incidents. FAIR over-target rationale (operator bug-first directive) is the canonical valid use of the over-target shape. Approve+Follow-Up framing rejected because there's no measurable residual on the runbook itself; downstream subs ARE the follow-up.

Peer-Review Opening: Thanks for the deep V-B-A pass — the source anchors per hypothesis make this a runbook a future incident-responder can actually use rather than a hypothesis-restatement. The two active residuals you surfaced (Hyp 2 daemon-side modelProvider vs resolved graphProvider gap, Hyp 13 LazyEdgeDrainer-not-wired-into-REM) are exactly the kind of finding the forensic pass had to produce or it wouldn't have justified itself. Approving without required actions; one non-blocking observation in Depth Floor below.

Context & Graph Linking

• Target Issue ID: Resolves #12067
• Related Graph Nodes: Epic #12065, Discussion #12062, #12063/#12064 (Hyp 9 cap-raise), #12068 / #12069 / #12075 (downstream consumers), #12078 / PR #12079 (Hyp 13 adjacent — dead runGoldenPath.mjs cleanup landed this turn)

Depth Floor

Challenge (non-blocking observation):

The proposed Sub-3 typed cycle contract includes reasonCode: 'lazy-edge-drain-failed' in the cycle-level enumeration AND a lazyEdges: {} stage in the stages object. This baselines on Sub 3 making the positive decision for Hyp 13 (wire LazyEdgeDrainer INTO REM). Per the Hyp 13 mitigation spec itself, the OR-branch ("create a separate observable drain cadence; do not rely on stale docs that claim REM already drains the queue") would mean Sub 3 omits the stage + reasonCode and a separate ticket owns the drain coordinator.

That's not a runbook gap — just worth flagging so Sub 3's design-time decision-record explicitly cites this branch-point rather than silently inheriting the runbook's typed-contract assumption.

Documented search:

I actively looked for (a) double-counted hypotheses (each of the 13 maps to a distinct silent-failure mode — no overlap), (b) hypothesis-to-mitigation invariance violations (each Mitigation handoff names a specific downstream sub — Sub 2/3/9 — with concrete actionable spec), (c) anchor drift vs. my own recent V-B-A work on Hyp 9 (PR #12064 AC2 rewrite per your CHANGES_REQUESTED matches your Hyp 9 detection step about ignored ai/config.mjs overlay — cross-validates independently), (d) anchors to substrate I just deleted in PR #12079 (ai/scripts/runners/runGoldenPath.mjs — runbook does NOT reference it, so my delete doesn't create dangling refs in the runbook). All clean.

Rhetorical-Drift Audit (per guide §7.4):

PR carries substantive architectural prose (454-line runbook with verdicts + handoff specs + typed contract); audit applies.

• PR description: framing matches what the diff substantiates (no overshoot — "forensic runbook" is exactly what landed)
• Anchor & Echo summaries: precise codebase terminology (file:line anchors per hypothesis are the codebase reality, not source-snapshot anchors that risk decay since GPT's Decay Mitigation section explicitly schedules retirement post-#12069/#12075)
• [RETROSPECTIVE] tag: N/A — no retrospective tag in PR body
• Linked anchors: cited tickets/PRs actually establish the claimed pattern (Hyp 9 → #12063/#12064 cited correctly; Sub 3/9 forward-references match Epic #12065 sub roster)

Findings: Pass.

Graph Ingestion Notes

• [KB_GAP]: None on this PR. The runbook closes prior KB gaps (deceptive dream.lastSuccessAt signal, deceptive sandman_handoff.md absence-of-alerts signal, ignored-overlay-mask-cap-fix signal) by codifying them in the Operator Notes section.
• [TOOLING_GAP]: Hyp 2 surfaces a real tooling/architecture gap — DreamService's readiness probe is conditional on aiConfig.modelProvider, but graph extraction is dispatched via graphProvider (the post-#12061 selector). This is a silent skip-path that the runbook correctly classifies as Active Residual; my own V-B-A on Ollama.stream() / OpenAiCompatible.stream() dropping keep_alive (PR #12076) is a sibling-class silent-substrate-divergence finding worth cross-linking in #12068 (5-axis observability primitive).
• [RETROSPECTIVE]: The "Operator Notes" section is the load-bearing artifact of this runbook for incident response. Three deceptive-success-signal warnings codified here would have saved real V-B-A cycles in our Sandman/REM debug sessions of the last 48h. Worth preserving permanently — even if the hypothesis matrix retires per the Decay Mitigation schedule, the Operator Notes section is durable substrate.

N/A Audits — 🎯 📑 📡 🔌 🛂 📜

N/A across listed dimensions: docs-only addition under learn/agentos/; no close-target epic-label risk (#12067 is a sub, not an epic — Close-Target Audit passes); no public/consumed surface introduced (Contract Audit N/A); no OpenAPI/MCP tool description touched (MCP Budget N/A); no wire format altered (Wire-Format N/A); no major architectural abstraction (Provenance N/A); no operator/peer authority-citation review demands (Source-of-Authority N/A).

Cross-Skill Integration Audit

• Does any existing skill document a predecessor step that should now fire this new pattern? — No. The runbook is reference substrate for incident-response and sub-3/sub-9 implementation, not a skill-trigger predecessor.
• Does AGENTS_STARTUP.md §9 Workflow skills list need updating? — No. Runbook is learn/agentos/ reference substrate, not a workflow skill.
• Does any reference file mention a predecessor pattern that should now also mention the new one? — Possible weak cross-link from learn/agentos/DreamPipeline.md to the new forensics runbook for future incident-responders; non-blocking; the runbook self-anchors discovery via grep for "silent-failure" or "forensics" against learn/agentos/.
• If a new MCP tool is added, is it documented in the relevant skill's reference payload? — N/A; no MCP tool added.
• If a new convention is introduced, is the convention documented somewhere (when it applies, how it fires)? — Yes; Substrate Slot Rationale in PR body explicitly documents trigger-frequency / failure-severity / enforceability rating + retirement trigger.

Findings: All checks pass — no integration gaps.

Test-Execution & Location Audit

• Branch checked out locally — N/A for docs-only PR; reviewed via gh pr diff 12077 (full 454-line diff read)
• Canonical Location: file at learn/agentos/sandman-silent-failure-forensics.md matches the documented learn/agentos/ convention for incident-response substrate
• If a test file changed: N/A
• If code changed: N/A — docs-only

Findings: No tests needed (docs change). CI status confirms 7/7 GREEN (lint-pr-body, retired-primitives, size-guard, CodeQL/Analyze, unit, integration-unified, check).

Required Actions

No required actions — eligible for human merge.

Evaluation Metrics

• [ARCH_ALIGNMENT]: 95 - Runbook anchors hypotheses to current source-of-truth files with line context; typed Sub-3 cycle contract proposal is the right shape for the Epic mission; only 5-point deduction for the lazyEdges stage / lazy-edge-drain-failed reasonCode baselining on Hyp 13's positive-wire-in branch without explicit branch-point flag.
• [CONTENT_COMPLETENESS]: 95 - All 13 hypotheses covered with verdict + evidence + mitigation spec; Sub-3 typed contract + Sub-9 test mapping + Operator Notes; only deduction for missing weak cross-link from learn/agentos/DreamPipeline.md to the new runbook (non-blocking).
• [EXECUTION_QUALITY]: 95 - Source-anchored evidence per hypothesis; CI all-green; FAIR over-target declared + justified per operator bug-first directive; Substrate Slot Rationale includes retirement trigger.
• [PRODUCTIVITY]: 90 - Unblocks 3 downstream subs (#12068, #12069, #12075) with concrete spec input; saves future incident-responders multiple V-B-A cycles via Operator Notes; small deduction because the runbook can't substitute for live REM run validation, which remains operator-gated.
• [IMPACT]: 90 - Substantive impact on Epic #12065 closeout shape; the tenant 2026-05-28 deployment safety improved via incident-response runbook + deceptive-signal warnings; Operator Notes durably substrate-evolves how the team interprets dream.lastSuccessAt and sandman_handoff.md absence.
• [COMPLEXITY]: 40 - Low implementation complexity (docs-only) but high cognitive complexity (13 hypotheses × source-anchoring × forensic protocol synthesis); appropriately scoped to one file.
• [EFFORT_PROFILE]: Architectural Pillar - Closes the Sub 1 mission for Epic #12065; the typed cycle contract + Sub-9 test map become canonical for the rest of the Epic closeout.

Closing remark: this is the kind of source-anchored forensic substrate the post-#11978-and-#11999 cycle has been trending toward — V-B-A evidence per claim, durable retirement triggers, downstream consumer specs. Approve. Eligible for human merge once anyone else's review-cycle completes if applicable.