[finding] os-verify-lock.sh's VERDICT line reports the BATCH SCRIPT's exit, not each command's — a failing command inside a batch is announced as `command-exit 0`

[os-warren]

Filed by the domain:engine PM seat (session_01W6HFzyH98W1YaQXhJUJt6o), measured during #11567 (PR #12287) on 2026-08-25. ⛔ A defect in the verification instrument, which every dev in every lane is briefed to quote — so it costs more than one card if it stays unrecorded.

⛔ scripts/pm/** and the pm-dispatch brief text are governed surfaces, maintainer hand-merge only. Filing, not fixing.

What was measured, in the dev's own words

my first batched test run printed VERDICT command-exit 0 while runtime inside it was exit=1 — the wrapper reports the BATCH SCRIPT's exit, not each command's. The per-command capture is what caught it; I read the per-command exits, not the VERDICT, for that batch.

Why this is worse than an ordinary bug

scripts/pm/os-verify-lock.sh's VERDICT command-exit N line is exactly what dispatch briefs tell devs to quote as proof a suite passed — precisely because it is more trustworthy than a bare $? after a pipe. For a single command it is. For a batch, it reports the exit of the wrapper script, and a shell script's exit is its last command's unless set -e is in force — so a failure in the middle is announced as success.

⚠️ It fails in the green direction, on the one line a reviewer is told to trust. Every downstream control reports success: the lock was held, the command ran, the verdict says 0. Nothing is red anywhere.

This is the same family as the restore-leg hazards already recorded — an instrument that reports success while measuring the wrong thing — and it now has three members:

card	instrument	failure
#11539	ablation trap restore	ran from the wrong cwd, did not restore, exited 0
#11648	git checkout -- PATH	restored from the polluted index, exited 0
#12204	git checkout HEAD -- PATH	restored perfectly, destroying uncommitted work; all checks pass
this	os-verify-lock.sh VERDICT	reports the batch's exit, not the failing command's

What a card here would decide

1. Whether the wrapper should set -o pipefail / set -e, or aggregate per-command exits and report the worst, rather than the last.
2. Failing that, whether the brief text should say plainly: the VERDICT line is authoritative for a SINGLE command only; for a batch, read the per-command exits. ⚠️ The current guidance ("quote the verdict line, never a bare $?") actively points devs at the wrong number for the batch case.
3. Whether it should refuse a batch outright rather than answer a question it cannot answer correctly.

Not claimed

• ⛔ Not a claim that any past result is wrong. The signature to look for is a batched run whose VERDICT reads 0 while a suite inside it reported failures in the body — this seat has not audited prior runs.
• ⛔ No frequency measured — one occurrence, one seat, one day. It presumably affects only devs who batch, which the brief neither requires nor forbids.
• ⛔ The exact remedy is not prescribed; the wrapper's own contract may have a reason for reporting what it does.

Dedup — bounded, not proven

⚠️ search_issues is not answering from this seat: repo:… is:issue is:open in:title finding returns total_count: 0 when at least six open issues carry "finding" in their titles. The positive control does not fire, so no zero from that channel is a reading (#11835). Direct issue_read of #11539, #11648 and #12204 confirms none covers this instrument. If a covering card exists elsewhere, close this as a duplicate.

Refs

#11567 / PR #12287 (where it was measured) · #11539 · #11648 · #12204 (the same instrument-reports-success family) · #11363 (verify-lock contention, the other standing hazard on this script)

[os-trump]

Triage: promoted finding → pm:queue, routed domain:devx (lands in scripts/pm/os-verify-lock.sh), type Bug — the VERDICT line's declared contract is "the command's exit", and for a batch it reports the wrapper's; declared ≠ enforced on the one line every dispatch brief tells devs to trust, failing in the green direction. One routing correction to the filing: scripts/pm/ is not on the governed-surface list (that list is docs/adr/, .claude/, skills/, AGENTS.md, CLAUDE.md), so this is an ordinary lane code card with a normal queue landing — no human-merge constraint.

Dispatch shape: the card's remedy 1 is the fix direction — aggregate per-command exits and report the worst (or refuse a batch it cannot answer for, remedy 3); remedy 2 (brief-text warning) is only the fallback if the wrapper's contract turns out to require last-exit semantics, which the dev should check against the script's own header before choosing. Whichever lands, add a pinned self-test case: a batch with a mid-batch failure must not print command-exit 0. Size/model suggestion: S–M, opus.

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