[deep-report] Investigate PR Sous Chef workflow 26% failure rate #63864

Description

Live workflow-run log analysis for a 9-hour sample window (2026-09-27 09:31–18:33Z, 100 runs pulled via agenticworkflows logs) shows the PR Sous Chef workflow at a 26% failure rate (9 failures / 35 runs) — by far the largest concentration of failures in the sample (observability_insights: "Workflow pr-sous-chef accounted for 9 failure(s) across 35 run(s)"). This corroborates two independent discussion reports this week: #63694 (Agent Job Health Report) flagged a fleet-wide 17% failure rate "~2x baseline, persisting 2+ windows untracked" with a Copilot CLI step cluster called out, and #63806 (Storify) narratively described a recurring "safe_outputs wobble in PR Sous Chef" as "self-correcting." The self-correcting characterization does not match the 26% failure rate measured live — this warrants a root-cause investigation rather than continuing to treat it as transient noise.

Expected Impact

Identifying and fixing the root cause could meaningfully improve fleet-wide reliability, since PR Sous Chef is one of the two highest-frequency workflows in the fleet (35 of 100 sampled runs).

Suggested Agent

Failure Investigator (existing agent referenced in the run sample as "[aw] Failure Investigator (6h)") or a new dedicated investigation task against the pr-sous-chef workflow's recent failed run logs.

Estimated Effort

Medium (1-4 hours) to diagnose; fix effort depends on root cause.

Data Source

DeepReport Intelligence Briefing analysis, 2026-09-27 — live agenticworkflows logs sample (100 runs, 2026-09-24 to 2026-09-27T08:46Z window, partial due to count limit) cross-referenced with Discussions #63694 and #63806.

Generated by 🔬 Deep Report · claude · agent · 270.9 AIC · ⌖ 10.6 AIC · ⊞ 12.9K · ◷

• expires on Sep 29, 2026, 10:42 AM UTC-08:00