Test-suite executions consume 40% of a cloud implement run's wall clock, and some re-derive output the run already had

[The01Geek]

Problem Statement

Test-suite executions are the largest single line item in a cloud implement run's wall clock, and some of them buy nothing. Across the five most recent cloud implement runs (measured 2026-08-24 from their Actions transcripts: runs 32774995051, 32775237213, 32777884173, 32781679682, 32781839046), 13 suite executions consumed 94.5 minutes — 40.6% of all agent wall clock.

Three of those 13 (18.3 min) ran on a tree with zero changes since the previous execution. They were launched purely to see output the previous execution had already produced and then discarded through a pipe. The agents' own rationales, quoted from the transcripts: "Let me get explicit PASS evidence for the #1911 assertions." (6.1 min), "Let me get the actual FAIL lines to diagnose." (6.2 min), "Let me re-run monolith capturing the full recap to a file" (6.0 min). Two further executions (12.8 min) were spent characterizing assertions the agents concluded were environmental. Two of the five runs died at ~71 minutes on an expired credential; one of those had spent 12.3 minutes on the zero-change re-runs.

This issue covers six separable defects that each produce or permit an avoidable suite execution, or misprice one. They are independent and may ship as separate PRs.

Current Behavior

Environment fact: items 1–4 and 6 happen regardless of environment. Item 5's failures are environment-dependent and that dependence is the defect.

Item 1 — the shard runner is the only one of the three that never names its retained log

This is a consistency gap, not a missing convention. Two of the three runners already announce where their output was retained; the third does not, so an agent that pipes its output away has no way to get it back except by re-executing.

• Verified: lib/test/run-parallel.sh prints its retained-log root and, on failure, directs the reader away from re-running: it contains "run-parallel: retained logs: %s" and "aggregate FAILED — read the retained logs above rather than re-running".
• Verified: lib/test/run-module.sh names its own retained log in its summary block: it contains "printf 'Log: %s\n'".
  Observed live on 2026-08-24: running that module runner on phase2-durability-checkpoint printed its pass/fail summary followed by a Log: line pointing under .prflow/tmp/test-module-logs/.
• Verified: lib/test/run-shard.sh retains its full output at .prflow/tmp/shard-tally//log.txt and echoes it, but prints no path line; the echo is the file's only use of it, introduced by the comment "# Echo the captured log so the shard job's own log carries the detail too."
• Verified: CLAUDE.md tells the cloud tier to consume that echo through a tail pipe — "rather than taking its whole echoed log into context" — which discards everything above the tail window with no stated way to recover it.

Nothing under skills/ or agents/ mentions the retained log at all, so a consumer repository inherits none of this. Re-derive: grep -rn "shard-tally|retained log|run-shard" skills/ agents/ .prflow/prompt-extensions/ returns nothing (checked 2026-08-24).

Item 2 — the single flight does not cover a shard run

• Verified: CLAUDE.md scopes the consult obligation to a full-suite relaunch and points only at the coordinator's logs: "before any full-suite relaunch" and "and the retained shard logs instead of relaunching".

A mid-iteration shard run is therefore outside the obligation, and the flight suppressed none of the three zero-change re-runs above. scripts/verification-flight.py already implements lease expiry, checkout-drift-to-stale, and checkout_verified, and it correctly does not suppress a post-edit relaunch — the gap is the scope of the prose, not the helper.

Coupled mirror — the single-flight coordination paragraph exists in FOUR places and all four must move together: skills/review-and-fix/references/fixing.md (Step 3, item 4), skills/implement/phases/phase-3-ac-gate.md (§3.4), skills/implement/phases/phase-4-documentation.md (§4.3), and CLAUDE.md.

Item 3 — the fix loop's per-iteration test run has no narrowing clause

• Verified: skills/review-and-fix/references/fixing.md item 4 opens "Run tests after all fixes. Check CLAUDE.md, README, or project configuration for the project's test and lint commands." — with no instruction to narrow.
• Verified: skills/implement/phases/phase-2-sweeps-quality.md already carries the clause item 4 lacks: "Run the narrowest covering test before the broadest."

The fix loop runs that step once per iteration, up to max_iterations (default 5 in .prflow/config.schema.json), plus the Step 2.6 shadow and the fix-delta gate's inner attempts, which skills/review-and-fix/references/fix-delta-gate.md states are "not counted toward the $MAX_ITERS cap". .prflow/prompt-extensions/review-and-fix.md patches this repository-locally, but a prompt extension ships to no consumer, so every consumer gets the unnarrowed rule. Measured 2026-08-24: across the five runs, lib/test/run-module.sh was invoked zero times — every one of the 13 executions was a monolith shard or the whole-suite coordinator.

Item 4 — two loop-exit whole-suite triggers are not caller-scoped

• Verified: skills/review-and-fix/references/loop-exit.md carries a base-merge trigger — "Loop-exit suite rule. Re-run the project test suite at Loop Exit whenever a Checkpoint-3 merge landed after the loop's last suite run" — which fires on any recorded base_checkpoint.token equal to UPDATED and fails closed on an absent comparand.
• Verified: skills/review-and-fix/references/loop-exit.md carries a second, independent trigger: "Identity-keyed refresh (recovery arm)." — one suite re-run whenever claim-time candidate identity differs from the verification record's.
• Verified: .prflow/prompt-extensions/review-and-fix.md scopes only the loop's terminal gate by caller — "Whose terminal the loop's gate is depends on the caller." — and states "the obligation is owned exactly once by Phase 4.3."

The two triggers above are not the terminal gate, so they fire regardless of caller. Inside the implement command they can therefore double-pay against Phase 4.3's exactly-once whole-suite obligation.

Item 5 — flaky refresher assertions mandate an expensive characterization loop

The credential-refresher liveness arms (#487 arm13, #491 arm20b, #1882 arm1882k, all resident in lib/test/run.sh) go RED only after repeated heavy monolith runs in one sandbox. Measured 2026-08-24: two executions totalling 12.8 minutes were spent characterizing them, and both agents concluded the failures were environmental.

• Verified: CLAUDE.md forbids treating such a red as known-flake: "There is no known-flake set — every FAIL is a real failure to diagnose."
• Verified: CLAUDE.md already names the remedy: "A red assertion that reproduces only under pool saturation is a defect in that assertion's slack budget: fix the assertion, do not re-run the suite hoping for green."

The rule is correct and should not be weakened; the assertions are what must change. A separate credential-refresher investigation is in flight — no open issue for it was found on 2026-08-24 (searches: refresher, credential expired token run died) — so check for one before assuming these fixes are independent.

Item 6 — CLAUDE.md prices the suite with measurements that have already rotted

The routing rule that sends a run.sh-resident surface to the monolith shard is justified by a dated pair of runtimes. Both are now wrong, and the rule they support does not depend on their exact values.

• Verified: CLAUDE.md justifies that routing rule with a dated measurement: "measured on the cloud implement tier at ~10.5 min against ~3.9 min (2026-08-04)".
• Verified: CLAUDE.md already states the convention such a figure violates: "Prefer generated evidence over exact checked-in numbers".

Measured 2026-08-24 on the same tier, from the transcripts of the five runs above: the coordinator took 16.0 minutes and the monolith shard 5.9–12.6 minutes. Both checked-in figures are low by roughly 1.6x after twenty days, while the qualitative claim they support — that the coordinator meaningfully exceeds one shard on that tier — still holds and needs no number. The same rot applies to any other measured duration CLAUDE.md states for a suite command. A duration a run must literally pass as a command operand is not a measurement and is not in scope here.

Desired Behavior

Every test-suite runner names the log it retained, and an agent that needs more of a run's output re-reads that log instead of re-executing. The single-flight consult obligation covers every suite execution and every retained log, not only a whole-suite relaunch. The fix loop narrows its per-iteration test run the way the implement phase already does, in the shipped body a consumer receives. The two loop-exit whole-suite triggers are caller-scoped on the axis the run already has. The three refresher assertions pass under sandbox contention. CLAUDE.md prices the suite with claims that stay true as the suite grows, rather than with runtimes that rot.

User Impact

A consumer running the implement command pays for suite executions that produce no new information, on the tier where a run can also die on an expired credential mid-way. Recovering an already-produced result costs a re-execution rather than a file read.

Technical Context

Scope note: The files and details below are the known starting points, not the full list. Before implementing, trace the change through the codebase to find every affected call site, consumer, and layer — this issue maps the work, it does not bound it.

• Relevant Classes/Files — lib/test/run-shard.sh, lib/test/run-parallel.sh, lib/test/run-module.sh, scripts/verification-flight.py, skills/review-and-fix/references/fixing.md, skills/review-and-fix/references/loop-exit.md, skills/implement/phases/phase-3-ac-gate.md, skills/implement/phases/phase-4-documentation.md, .prflow/prompt-extensions/review-and-fix.md, CLAUDE.md, lib/test/run.sh.
• Architecture Alignment — items 1–4 are prose and helper-output changes on existing surfaces; the caller axis item 4 needs already exists (the focused-selection sink routes on the issue workpad versus iter-N.json).
• Cross-layer Impact — shell test runners, shipped skill bodies, repository memory, and one repo-local prompt extension. Item 6 touches CLAUDE.md only.

Out of scope, stated as context only. lib/test/modules/coverage-map.json records 469 entries under run_sh_blocks — assertion blocks resident in lib/test/run.sh with no covering focused module — so for those surfaces the narrowest covering test is the roughly six-minute monolith shard. That is a cost-per-execution problem, not an execution-count problem, and belongs in its own issue.

Acceptance Criteria

• lib/test/run-shard.sh prints a line naming the absolute path of the log it retained, on both its passing and failing exits.
• CLAUDE.md's tail-pipe bullet states that the tail read is the first read, that every later slice of that run's output comes from the retained log, and that re-executing a suite to obtain output already retained is forbidden.
• A shipped body under skills/ tells the agent that a suite runner retains its output and that further output is re-read from the retained log rather than obtained by re-executing.
• The single-flight consult obligation in all four copies — skills/review-and-fix/references/fixing.md, skills/implement/phases/phase-3-ac-gate.md, skills/implement/phases/phase-4-documentation.md, and CLAUDE.md — is scoped to any suite execution and any retained log, not only a full-suite relaunch, and the four copies remain consistent with each other after the change.
• skills/review-and-fix/references/fixing.md item 4 instructs the run to execute the narrowest covering test before the broadest, in the shipped body rather than in a prompt extension.
• The loop-exit base-merge trigger and the identity-keyed refresh trigger in skills/review-and-fix/references/loop-exit.md each state that they do not fire when the loop's caller is the implement command, and each still fires when the caller cannot be established.
• Item 4's caller scoping introduces no new flag, field, or counter, and reads the same caller axis the focused-selection sink already routes on.
• The Keep writer-job push and gh credentials fresh past the App token's 60-minute lifetime #487 arm13, Keep writer-job push and gh credentials fresh past the App token's 60-minute lifetime #491 arm20b and Sign the credential refresher's JWT without openssl process substitution so long cloud runs keep GitHub access on non-Linux runners #1882 arm1882k assertions in lib/test/run.sh pass when the suite is run repeatedly in one sandbox, and each change is to the assertion's own slack budget rather than to CLAUDE.md's no-known-flake rule.
• CLAUDE.md's no-known-flake rule and its slack-budget remedy are both present and unweakened after the change.
• CLAUDE.md states no measured wall-clock duration for a test-suite command, the monolith-shard-versus-coordinator comparison included; each is either dropped in favour of the qualitative claim it supported, or replaced by a pointer to where the figure can be measured.
• Every duration CLAUDE.md retains is one a run passes verbatim as a command operand, or one that names a configuration setting owned by another file; a configuration duration is referred to by its setting name rather than restated as a literal, so the setting's own file stays the single source.
• The full test suite passes and shellcheck reports no warning on every changed shell file.

Implementation Notes

• Approach — mirror lib/test/run-parallel.sh's and lib/test/run-module.sh's existing retained-log announcement into lib/test/run-shard.sh, then widen the three prose scopes (tail-pipe consumption, single-flight coverage, per-iteration narrowing) and caller-scope the two loop-exit triggers. Item 5 is separate work on three assertions.
• Relevant files — likely lib/test/run-shard.sh, CLAUDE.md, skills/review-and-fix/references/fixing.md, skills/review-and-fix/references/loop-exit.md, skills/implement/phases/phase-3-ac-gate.md, skills/implement/phases/phase-4-documentation.md, and plausibly .prflow/prompt-extensions/review-and-fix.md (whose repo-local patch item 3 supersedes) and lib/test/run.sh plus its refresher fixtures.
• Code Patterns — lib/test/run-parallel.sh's terminal printf block is the pattern for item 1; the focused-selection sink's existing caller axis is the pattern for item 4.
• Testing Strategy — a module-level assertion that lib/test/run-shard.sh's output names its retained log on both a passing and a failing shard; assertions that each of the four single-flight copies carries the widened scope; for item 5, run the three arms repeatedly in one sandbox and prove they stay green, and prove each amended assertion still goes RED against a mutated copy of the behaviour it pins.
• Documentation Needed — CLAUDE.md is edited by items 1, 2 and 5 as part of the change itself; no separate documentation deliverable. none.
• Potential Gotchas — the five items are separable and may ship as separate PRs, but items 1 and 2 both edit CLAUDE.md and item 2 edits four coupled copies, so a partial edit leaves the copies disagreeing. Item 5 must not be "fixed" by adding a known-flake exemption.

[The01Geek]

/prflow:implement

[github-actions]

PRFlow Workpad — Issue #1923

Status: 🎉 Complete
Branch: issue-1923-test-suite-executions-consume-40-of-a-cloud
Run: View run
PR: #1929
Last updated: 2026-08-25 00:53 UTC

Progress

• Setup — branch & workpad
  • prompt extension resolved: implement
  • 23:35:56 — /prflow:implement run started
  • 23:36:37 — Claude job setup complete; invoking agent
  • 23:40:00 — agent entered Phase 1 setup; workpad triage passed
  • 23:40:06 — agent initialized; Phase 1 workpad hydrated
  • 23:40:21 — resume-kind: fresh
  • 23:40:21 — classification: non-bug — unlabelled improvement issue: reduces suite-execution wall clock via runner-output/prose/scope changes; describes no malfunction
  • 23:40:43 — Phase 1.3.5: early dependency preflight passed (PROCEED)
  • 23:42:44 — issue-claim audit (projection): every Desired Behavior obligation is represented in the resolved acceptance criteria — pass complete
  • 23:42:46 — issue-claim audit (count): claimed '469 entries under run_sh_blocks', verified '469' at HEAD; claimed 'default 5' for max_iterations, verified '5' at HEAD
  • 23:42:48 — issue-claim audit (negative-scope): no scope-exclusion claims found — pass complete
  • 23:42:50 — issue-claim audit (policy): no policy-referencing AC claims found — pass complete
  • 23:42:51 — issue-claim audit (execution-capability): cloud tier — no acceptance criterion requires editing .github/workflows/; nothing to defer
  • 23:42:53 — issue-claim audit (verified-premise): re-checked 14 Verified: bullet(s) at HEAD — 14 hold, 0 unestablished; no premise refuted; no ungraded claims found
• Implement
  • code + sweeps
  • 23:43:55 — entered Phase 2
  • 23:48:57 — scope decision: this PR delivers issue items 1, 2, 3, 4 and 6 (retained-log announcement, tail-pipe + single-flight scope widening across the four copies, fix-loop narrowing clause, loop-exit caller scoping, and CLAUDE.md duration de-rot). Deferred (verbatim): the item-5 credential-refresher slack-budget assertions (Keep writer-job push and gh credentials fresh past the App token's 60-minute lifetime #487 arm13 / Keep writer-job push and gh credentials fresh past the App token's 60-minute lifetime #491 arm20b / Sign the credential refresher's JWT without openssl process substitution so long cloud runs keep GitHub access on non-Linux runners #1882 arm1882k) and the coupled no-known-flake/slack-budget-remedy guard — separable heavy work the issue itself frames as 'separate work on three assertions' requiring repeated in-sandbox monolith runs. Tracked in a follow-up filed in Phase 4.0.
  • 23:48:57 —
  • 23:48:57 —
  • 23:52:45 — test-first: run-shard.sh retained-log line — RED-first in lib/test/modules/parallel-suite-runner.sh (2 assertions failed for absence, then GREEN 170/0 after the run-shard.sh edit); mutation is the removal of the printf line itself, which the assertions catch. Remaining ACs (tail-pipe/single-flight/narrowing/caller-scoping/durations) are agent-executed prompt prose with no automated boundary (issue Refresh the frozen pin identities so the pin corpus can track a renamed cap and cover issue-797's new operative sentences #843/Retire the prose-pin stock and its governance subsystem: generalize the #843 no-coverage-for-agent-executed-prose decision #876 recorded decision) — no wording pins added; the review pass is the control.
  • 23:52:45 — §2.3 sweeps: diff shape = contract-add (run-shard.sh stdout line) + prose (CLAUDE.md) + test-add. Ran 2.3.4 boundary: run-parallel.sh captures shard stdout into a per-shard log file (line 507 exec > $shard_log) and recombines via shard-tally.py reading the tally dir, so the new stdout line is not parsed and breaks nothing. 2.3.4a self-authored-claim: CLAUDE.md's 'run-shard.sh names the absolute path of the log it retained' and 'every runner names the log it kept' verified against run-shard.sh/run-parallel.sh/run-module.sh. 2.3.4b coverage-universal 'every runner (run-parallel.sh, run-shard.sh, run-module.sh)' is a bounded three-runner enumeration, each verified. 2.3.6 error-handling: no new error path. No enum/peer/delete triggers fired.
  • 23:52:45 — CLAUDE.md edited directly under the autonomous-implement carve-out (Conventions 'CLAUDE.md edit carve-out'): AC2/AC10/AC11 require the tail-pipe, single-flight and duration edits, so the orchestrator made them itself rather than invoking revise-claude-md mid-run.
  • 23:52:45 — batched-regeneration: run (lib/test/regenerate-artifacts.py exit 0, all rows clean; exact-module-floors not measured — expected default)
  • 23:55:26 — Writing-skills evidence: skills/review-and-fix/references/fixing.md mode=subagent skill-loaded=yes (superpowers:writing-skills present in available-skills and invoked by the dispatched subagent) guidance-applied=yes (Match-the-Form: surgical clarifying additions kept minimal, no scope creep) pressure-scenario=no (clarifying-rule additions with no behavior-steering ambiguity) micro-tests=no (prompt prose with no automated boundary; no wording variants to control)
  • 23:55:26 — Writing-skills evidence: skills/review-and-fix/references/loop-exit.md mode=subagent skill-loaded=yes (superpowers:writing-skills present and invoked by the dispatched subagent) guidance-applied=yes (Match-the-Form applied to caller-scoping rule prose) pressure-scenario=no (rule text is exact and unambiguous; the suppression is a stated condition with no rationalization space to elicit) micro-tests=no (prompt prose with no automated boundary)
  • 23:55:26 — Writing-skills evidence: skills/implement/phases/phase-3-ac-gate.md mode=subagent skill-loaded=yes (superpowers:writing-skills present and invoked by the dispatched subagent) guidance-applied=yes (Match-the-Form: scope-clarifying cross-reference sentence) pressure-scenario=no (scope-clarifying addition, not a new behavior-shaping rule) micro-tests=no (single fixed sentence; no wording variance to test)
  • 23:55:26 — Writing-skills evidence: skills/implement/phases/phase-4-documentation.md mode=subagent skill-loaded=yes (superpowers:writing-skills present and invoked by the dispatched subagent) guidance-applied=yes (Match-the-Form: scope-clarifying cross-reference sentence consistent with the other copies) pressure-scenario=no (scope-clarifying prose restating an existing CLAUDE.md rule) micro-tests=no (single fixed sentence; no wording variance to test)
  • 23:58:40 — §2.3.4b coverage-claim sweep: ran stale-prose-lint.py --worktree over the merge-base branch delta (exit 0). One CU row, UNRESOLVABLE (informational, never gates): fixing.md item 4 'run the test that covers only the changed surface before the whole suite' — this is operative narrowing instruction mirroring phase-2-sweeps-quality.md §2.4 verbatim (the source AC5 directs the shipped body to mirror), grounded as Scoped/quoted-from-source, not a coverage universal about this change's own coverage. CLAUDE.md's 'every runner (run-parallel.sh, run-shard.sh, run-module.sh)' is a bounded three-runner enumeration, each verified. No STALE rows.
• Review
  • prompt extension resolved: review engine
  • prompt extension resolved: fix loop
  • prompt extension resolved: code-review reception
  • Classify diff (Phase 0.5)
  • Generate verification checklist (Phase 1)
  • Verify checklist (Phase 2)
  • Review agents (Phase 3)
  • Aggregate & verdict (Phase 4)
  • Run complete — everything this run owed
  • /simplify
  • review-and-fix
  • acceptance-criteria gate
  • 00:04:02 — /simplify: applied 1 finding (collapsed the run-shard pass/fail test halves into one loop; both exits still asserted per AC1; module GREEN 170/0). Skipped: (a) single-flight rule 'copied across 5 sites' — this is AC4's mandated four-copy coupled mirror and CLAUDE.md is not shipped to consumers, so the skill copies cannot be pointers to it; (b) 'factor the per-runner retained-log line into a shared helper' — out of scope, the issue frames item 1 as mirroring run-parallel/run-module's existing pattern, not refactoring their working output; (c) 'loop-exit caller-scoping restated per trigger' — AC6 requires each trigger to independently state its fire/not-fire condition.
  • 00:04:19 — Phase 3.3: invoking review-and-fix in PR mode with draft PR number 1929 (bare leading token) + --push-each-iteration --issue 1923
  • 00:04:19 — mid-phase resume point recorded
  • 00:16:15 — review coverage recorded (coverage=full, dispatch=attempted, roster=complete, checklist=complete)
  • 00:16:23 — Phase 3.3: review engine + fix loop ran inline. Extensions established via load-prompt-extension.sh ladder — content-present for review (engine), review-and-fix (fix loop), and receiving-code-review (reception). Initial roster (5 agents) + fix-delta re-review (2) + full blinded shadow (5): converged APPROVE, shadow full coverage, 0 new Critical/Important; 5 Suggestions fixed, 2 parked (unreachable cd-advisory, diminishing-returns test hardening).
  • 00:43:53 — 3.4 gate: all 10 in-scope criteria reconciled satisfied by the two AC verifiers; ticking by 1-based position. Verification flight (Phase 4.3 binds it): key d7a4452c3ca488a23a06742bf552b5b7d2b64782fb913c04b94bf9463db21900, terminal passed, head 3e70dee, whole suite 20901 passed / 0 failed.
• Documentation
  • 00:46:20 — Filed follow-up issue Fix flaky credential-refresher liveness assertions in lib/test/run.sh (widen slack budgets) #1931 for the deferred item-5 work (credential-refresher slack-budget assertions), labelled PRFlow,Deferred and registered as blocked_by Test-suite executions consume 40% of a cloud implement run's wall clock, and some re-derive output the run already had #1923. Drafter plan was clean (writing_standard_loaded: yes, slots from cache); its notes described a benign one-issue-for-both composition plus an added mutation-kill AC, not a degradation.
  • 00:46:20 —
  • 00:46:20 —
  • 00:49:29 — Phase 4.1: no documentation changes to commit (docs subagent ran clean / made no changes; docs=none — the CLAUDE.md edit was made by the implementation). Subagent noted docs/internal/claude-md-tiered-suite-rationale.md keeps the ~10.5/~3.9 figures as a dated historical snapshot (exempt) and focused_selection.py's docstring is unchanged code, both out of this PR's scope.
  • 00:52:04 — 4.2 claim audit (behavioral): checked — body's behavioral claims (run-shard.sh prints an absolute retained-log path unconditionally; prose files widened single-flight, added narrowing clause, caller-scoped two loop-exit triggers, dropped rotted durations) all traced to the shipped diff; no overclaim, no fix.
  • 00:52:04 — 4.2 claim audit (verification): checked — Test Plan bound to the three actual new assertions in parallel-suite-runner.sh (passing/failing/relative-dir); prose changes explicitly stated to have no automated test boundary (review is their control); no coverage overclaim.
  • 00:52:04 — 4.2 claim audit (artifact-existence): checked — Resolves scoped to items 1,2,3,4,6 of Test-suite executions consume 40% of a cloud implement run's wall clock, and some re-derive output the run already had #1923; item 5 (AC8/AC9) stated deferred to follow-up Fix flaky credential-refresher liveness assertions in lib/test/run.sh (widen slack budgets) #1931 (exists, blocked_by Test-suite executions consume 40% of a cloud implement run's wall clock, and some re-derive output the run already had #1923); changeset .changeset/issue-1923-suite-execution-cost.md exists; no Post-Merge Verification section (nothing in-scope is genuinely post-merge).
  • 00:52:04 — 4.2: PR body updated from placeholder; no code-level fix made.
  • 00:52:39 — checkpoint 4: observed token UP_TO_DATE — clean, proceeding to the publish decision
  • 00:52:46 — completion verification recorded (flight d7a4452c3ca4…, validated)
• PR marked ready
  • 00:53:17 — /prflow:implement run finished, PR published (gh pr ready): Test-suite executions consume 40% of a cloud implement run's wall clock, and some re-derive output the run already had #1929

Plan

• Item 1 — lib/test/run-shard.sh: print an absolute retained-log path line on every exit (pass and fail), mirroring lib/test/run-parallel.sh's "retained logs" and lib/test/run-module.sh's "Log:" announcements (reuse those existing patterns).
• Item 1 test — lib/test/modules/parallel-suite-runner.sh: RED-first behavioral assertion that run-shard.sh names its retained log on both a passing and a failing shard, using a fixture tree (mirror the existing psr_make_tree/synthetic-dispatcher pattern).
• Item 2/6 — CLAUDE.md tail-pipe bullet: state the tail read is the first read, later slices come from the retained log, and re-executing a suite to obtain already-retained output is forbidden.
• Item 2 — CLAUDE.md single-flight bullet: widen "before any full-suite relaunch" to any suite execution (whole-suite/shard/focused) and "retained shard logs" to the retained log whichever runner kept it.
• Item 6 — CLAUDE.md durations: drop the rotted "~10.5 min against ~3.9 min (2026-08-04)" comparison (keep the qualitative claim); refer to BASH_MAX_TIMEOUT_MS / BASH_DEFAULT_TIMEOUT_MS and the default per-command wall by setting name rather than restated literals; keep the 1200000 command operand verbatim.
• Item 2/AC3 — skills/review-and-fix/references/fixing.md item 4 (prompt-surface via writing-skills subagent): add a shipped-body sentence that a suite runner retains its output and further output is re-read from the retained log rather than by re-executing; widen the single-flight coordination scope to any suite execution and any retained log.
• Item 3/AC5 — skills/review-and-fix/references/fixing.md item 4 (same subagent): add "Run the narrowest covering test before the broadest." in the shipped body.
• Item 2 — skills/implement/phases/phase-3-ac-gate.md §3.4 (prompt-surface via writing-skills subagent): widen its single-flight consult obligation to any suite execution and any retained log, consistent with the other three copies.
• Item 2 — skills/implement/phases/phase-4-documentation.md §4.3 (prompt-surface via writing-skills subagent): same single-flight scope widening, consistent with the other three copies.
• Item 4 — skills/review-and-fix/references/loop-exit.md (prompt-surface via writing-skills subagent): caller-scope the Loop-exit base-merge suite trigger and the Identity-keyed refresh trigger so each states it does not fire when the caller is /prflow:implement and still fires when the caller cannot be established, reading the same caller axis (issue workpad vs iter-N.json) the focused-selection sink already uses — no new flag/field/counter.
• Versioning — add one .changeset/*.md (patch) after the draft PR exists, before review.
• AC12 — full suite passes and shellcheck clean on changed shell files.
• Deferred to follow-up (item 5, AC8/AC9): the Keep writer-job push and gh credentials fresh past the App token's 60-minute lifetime #487 arm13, Keep writer-job push and gh credentials fresh past the App token's 60-minute lifetime #491 arm20b, Sign the credential refresher's JWT without openssl process substitution so long cloud runs keep GitHub access on non-Linux runners #1882 arm1882k refresher slack-budget assertions in lib/test/run.sh — separable heavy work requiring repeated in-sandbox suite runs.

Acceptance Criteria

• lib/test/run-shard.sh prints a line naming the absolute path of the log it retained, on both its passing and failing exits.
• CLAUDE.md's tail-pipe bullet states that the tail read is the first read, that every later slice of that run's output comes from the retained log, and that re-executing a suite to obtain output already retained is forbidden.
• A shipped body under skills/ tells the agent that a suite runner retains its output and that further output is re-read from the retained log rather than obtained by re-executing.
• The single-flight consult obligation in all four copies — skills/review-and-fix/references/fixing.md, skills/implement/phases/phase-3-ac-gate.md, skills/implement/phases/phase-4-documentation.md, and CLAUDE.md — is scoped to any suite execution and any retained log, not only a full-suite relaunch, and the four copies remain consistent with each other after the change.
• skills/review-and-fix/references/fixing.md item 4 instructs the run to execute the narrowest covering test before the broadest, in the shipped body rather than in a prompt extension.
• The loop-exit base-merge trigger and the identity-keyed refresh trigger in skills/review-and-fix/references/loop-exit.md each state that they do not fire when the loop's caller is the implement command, and each still fires when the caller cannot be established.
• Item 4's caller scoping introduces no new flag, field, or counter, and reads the same caller axis the focused-selection sink already routes on.
• CLAUDE.md states no measured wall-clock duration for a test-suite command, the monolith-shard-versus-coordinator comparison included; each is either dropped in favour of the qualitative claim it supported, or replaced by a pointer to where the figure can be measured.
• Every duration CLAUDE.md retains is one a run passes verbatim as a command operand, or one that names a configuration setting owned by another file; a configuration duration is referred to by its setting name rather than restated as a literal, so the setting's own file stays the single source.
• The full test suite passes and shellcheck reports no warning on every changed shell file.

Devflow Reflection

Devflow Reflection (click to expand)

💡 Improvements

• 💡 Phase 3.4 AC gate + reconcile-ac-verifiers.py friction on a 'full test suite passes' verification-command criterion: the ac-claim-verifier correctly cannot establish a suite pass/fail verdict (it executes nothing), so it returns 'unestablished', which reconciles to a disagreement with the evidence verifier's 'satisfied' and BLOCKS a criterion that is in fact satisfied — forcing a second ac-claim-verifier dispatch reframed to do clause-mapping (does the command cover the criterion's clauses?) rather than establish the result. Consider: the ac-claim-verifier's charter for a verification-command criterion should default to the clause-mapping question (returning satisfied when the named command covers the criterion's clauses), so the first dispatch does not abstain and cost a re-dispatch; or reconcile-ac-verifiers.py could treat evidence=satisfied + claim=unestablished-by-charter for a verification-command criterion as satisfied rather than a blocking disagreement.

ℹ️ Notes

• ℹ️ skill-directory anchor resolved from the runner-reported base directory
• ℹ️ resume-precheck: both open-PR queries ran and returned none for this issue; workpad Branch line absent; no prior attempt to adopt
• ℹ️ Phase 3.4 acceptance-criteria gate — two-verifier reconciled dispositions (all 10 in-scope criteria satisfied; blocking: none). Verifiers: prflow:ac-evidence-verifier (ran the in-env whole suite via the single flight) + prflow:ac-claim-verifier (executed nothing). Reconciled via scripts/reconcile-ac-verifiers.py → all_satisfied: true. - AC1 satisfied (both) — run-shard.sh unconditional retained log: printf before the single exit; parallel-suite-runner 171/0 incl 3 new assertions (passing/failing/relative-dir). evidence_status_reported=satisfied, claim_status_reported=satisfied, undischarged_slots: none. - AC2 satisfied (both) — CLAUDE.md tail-pipe bullet: tail is first read, later slices from retained log, re-executing forbidden. - AC3 satisfied (both) — fixing.md item 4 shipped body: a suite runner retains its output in a named log, re-read rather than re-executed. - AC4 satisfied (both) — single-flight obligation widened in all four copies (CLAUDE.md:64, fixing.md:82, phase-3-ac-gate.md:15, phase-4-documentation.md:290), mutually consistent. - AC5 satisfied (both) — fixing.md item 4: narrowest covering test before the broadest, in the shipped body. - AC6 satisfied (both) — loop-exit.md base-merge + identity-keyed-refresh triggers each state: do not fire under /prflow:implement; fire for standalone; unestablished caller treated as standalone and fires. - AC7 satisfied (both) — caller read from the focused-selection-sink axis (issue workpad vs iter-N.json); no new flag/field/counter (CLAUDE.md:69 confirms no schema field). - AC8 satisfied (both) — CLAUDE.md states no measured wall-clock suite duration (the ~10.5/~3.9 comparison and the 20-min/10-min/600000 literals dropped; qualitative claim kept). - AC9 satisfied (both) — only 1200000 (command operand) and BASH_*_TIMEOUT_MS referred to by setting name (owned by devflow-implement.yml) remain. - AC10 (full suite + shellcheck) satisfied — evidence verifier ran shellcheck clean on both changed shell files and lib/test/run-parallel.sh via the single flight: 20901 passed, 0 failed, aggregate CLEAN, exit 0, 5/5 shards; flight terminal passed at .prflow/tmp/verification-flights/d7a4452c3ca488a23a06742bf552b5b7d2b64782fb913c04b94bf9463db21900.json bound to head 3e70dee. Claim verifier (re-dispatched with the verification-command clause-mapping charter) confirmed both clauses correspond to those commands over the changed-file set (ci.yml:377-381 lists both files in its shellcheck step; parallel-suite-runner is a registered coverage-map module). Reconciled satisfied. All dispositions parsed; undischarged_slots empty for every criterion.