jakman85andClaude Opus 5
8b5e950baa
pm-worker's command is pinned by admission with no args, so everything a caller could influence arrives in the environment — and the guards at the top of that script are what stand between an injected variable and a clone from the wrong host or a push to the wrong ref. Nothing exercised them, which makes them a claim rather than a control. probe-validation.sh asserts 17 refusals, each on BOTH a non-zero exit and the specific message, so a guard that stopped firing cannot pass by failing somewhere else. It covers a redirected git host, a real and reachable WRONG one (the egress policy permits tcp/443, so that case is not hypothetical), the right host with a smuggled path, 'main' and five other bad branch shapes, a malformed owner/repo, a bad mode, a bad issue number, and each missing credential. build-image.sh runs it inside the built image too. Writing it found three things: - the PM_BRANCH != main guard is unreachable while the pattern check above it holds, so the comment claiming it as the defence was wrong about which line does the work. Kept as an assertion independent of the regex; the comment now says so. - the EXIT trap ended in a failing test, which under set -e can replace the script's real exit code with that failure. - a provenance LOG LINE read a file through a redirect that set -o pipefail would have turned into a dead worker if the file were absent. Co-Authored-By: Claude Opus 5 (1M context) <[email protected]>
decisions/ — the handoff log, one file per entry
This directory is the decision log. ../DECISIONS-LOG.md is the frozen archive of
everything written before 2026-09-29 and is never edited again (see "The archive is
frozen" below).
Why this exists
DECISIONS-LOG.md was append-only in a single file, and every agent appended to its
tail. Two branches that both append hit the same last hunk, so git cannot
auto-merge them: the second one to be reviewed conflicts, and so does the third, and
the fourth. Measured on 2026-09-29: four of the five open PRs were unmergeable, and
DECISIONS-LOG.md was the only conflicting file in all four:
#22 fix/crafty-oauth2-proxy-signin CONFLICT (content): DECISIONS-LOG.md
#20 feat/conformance-job-template CONFLICT (content): DECISIONS-LOG.md
#19 feat/conformance-trigger-kubeconfig CONFLICT (content): DECISIONS-LOG.md
#18 feat/conformance-runner-image CONFLICT (content): DECISIONS-LOG.md
#17 feat/ci-is-the-approver clean (it touched no log entry)
Nothing was wrong with any of those changes. The log's storage format serialised work that was otherwise parallel, and it got worse with every concurrent branch: N branches produce N-1 rebases, each of which invalidates any gate run that preceded it.
The fix is the obvious one for concurrent appenders: stop sharing a file. Each handoff is its own file. Two agents writing handoffs touch disjoint paths, so there is nothing for git to merge and nothing to conflict. This scales to any number of parallel branches with zero coordination — which is the point, since the agents are deliberately isolated from each other in separate worktrees and cannot coordinate.
There is deliberately no index file and no counter. An index would be a shared
mutable file — exactly the thing that just failed — and a sequence number would have
two agents racing for 0043. The directory listing is the index.
Writing an entry
One file per handoff, named:
decisions/YYYY-MM-DD-<slug>.md
<slug> is lowercase [a-z0-9-]. Use your branch name's last segment — it is
already unique per unit of work, which is precisely the property the filename needs.
A branch fix/crafty-oauth2-proxy-signin handed off on 2026-09-29 writes:
decisions/2026-09-29-crafty-oauth2-proxy-signin.md
The file is YAML frontmatter followed by three required sections:
---
date: 2026-09-29
branch: fix/crafty-oauth2-proxy-signin
title: The Keycloak gate works — Crafty's own login was the wall
---
## What changed
Prose. What you actually did, and why.
## What I verified
The measurements, with their numbers. Quote the field you read, not the prose you
believed. Name the gate result and its exit code.
## What I did NOT verify
Everything else. An honest "UNVERIFIED" is worth more than an optimistic "green" —
this repo has been burned by the difference more than once.
All three headings are required and enforced (ci/decisions-log.sh). They are
CLAUDE.md §7's contract; making them a checked structure is what stops an entry
degrading into "done ✅".
Reading the log
The whole log, oldest first:
ls decisions/[0-9]*.md | sort
The current PM handoff — the newest entry. Ties within a day are broken by what landed
on main last, which is the honest answer, so ask git rather than the filename:
git log --diff-filter=A --format='%H' --name-only -- 'decisions/[0-9]*.md' \
| grep '^decisions/' | head -1
For a quick skim of who said what:
grep -H '^title:' decisions/[0-9]*.md | sort
The archive is frozen
DECISIONS-LOG.md is read-only history. Its SHA-256 is pinned in
decisions/ARCHIVE.sha256 and ci/decisions-log.sh fails the merge gate if the file
changes. That is not ceremony: without it, the next agent to read runbooks/ or an old
CLAUDE.md habit appends to the tail again and re-creates the conflict for everybody
else, silently, one PR at a time.
If the archive genuinely must change (a leaked credential to redact, say), that is a
deliberate, reviewed act: change it, run sha256sum DECISIONS-LOG.md > decisions/ARCHIVE.sha256,
and say in your handoff entry why. Re-pinning is visible in the diff. Appending is not.