Dispatch Codex

Dispatching codex (gpt-6-astra) as executor

If you are the codex executor and this file was loaded into your context: ignore it. It describes how the orchestrator dispatches you. It is not a task book.

This session is the orchestrator: it adjudicates design, writes the task book, runs every gate, all git, and accepts or rejects. The local codex CLI (default model gpt-6-astra at reasoning effort max, through the locally configured gateway) is the executor. Same division of labour as dispatch-grok, different machinery underneath — read §1 before assuming anything carries over.

A dispatch is a sandboxed subprocess of this session working in this session's checkout — not a second session in the iron-rule-13 sense. What rule 13 does forbid is two writers on one checkout: never dispatch while another session owns this worktree, and never run two dispatches (codex or grok) concurrently over overlapping paths.

1. What codex can reach on this machine

Read/write/network rows re-measured 2026-09-05 in this repository against codex-cli 0.153.4 with codex sandbox (deterministic, no model in the loop). Rows marked † come from a full exec probe run 2026-09-04 in the sibling private repo this skill was adapted from — same machine, same codex version; verify them against the first real dispatch here. Do not inherit this table into another repo or another codex version without re-measuring.

The env-file fence is a stash, not a rule

codex's sandbox restricts writes and network, never reads — and unlike grok there is no --deny Read(...) mechanism at all. Any file this user can read, a dispatched executor can read, and a read lands the content in the model's context at the gateway. This repo carries six gitignored env files, not one: apps/api/.env (the live catalog nmk_ key, OAuth client secret, image / trust / JWT secrets, the DB DSN), apps/web/.env (OG site key, image-bed and S3 secrets, CF cache token), apps/web/.env.prod (production credentials), docker/api.env, docker/web.env, refs/legacy/.env.prod. dispatch.sh discovers every env-shaped gitignored file instead of hard-coding that list, and removes them all for the duration: copied to 000-mode files under ~/.cache (mirroring the repo layout), deleted from the repo, restored and hash-verified per file afterwards. The stash is sealed on measured counts: read denied by DAC (mode 000), chmod / unlink denied because $HOME is not a writable root.

Residual, stated honestly: sibling repos' env files, ~/.ssh, the session scratchpad and everything else readable by this user stay readable. Two mitigations, both real but neither structural: the task book forbids reads outside the repo, and every command the executor runs is in events.jsonl — dispatch.sh greps it for suspect strings (.ssh, id_rsa, id_ed25519, auth.json, the stash prefix, /proc/*/environ, .env) and prints hits for the orchestrator to read in context. A hit is a line to go read, not automatically a leak — the original probe's .env hits were an instructed cat .env test.

If a dispatch dies hard (SIGKILL, machine loss) the trap may not restore: recover the newest ~/.cache/.codex-dispatch-* directory by hand (chmod 600 each file, move each back to the matching path inside the repo). dispatch.sh exits 3 and says so whenever a restore or a hash check fails.

Differences from grok that change how you write a task book

• codex has a shell. It runs commands in the sandbox — that is its native way of reading, editing and checking. It can run go build ./... / go vet ./... in apps/api, and — node_modules being local — pnpm -F web lint / pnpm -F web typecheck, so the task book may permit self-checking. Acceptance still re-runs every gate here; a green run from the executor is a courtesy, never proof.
• There are no per-path allow/deny grants. The whole repo is writable, full stop. Scope is bounded by the task book's writable-paths list plus git status --porcelain at acceptance — same as grok in practice (its --allow was a grant, not a whitelist), minus the documentation value of the grant flags. Put the writable paths in the task book, prominently.
• .git/ is read-only, so the executor cannot stage, commit, or branch even by accident. status / log / diff work.
• DB-backed tests cannot run in the sandbox (no network, and iron rule 14 reserves the launcher TEST_DATABASE_DSN for the orchestrator anyway). Tell the executor which tests not to run rather than letting it discover and report the failure.

2. The dispatch

export CODEX_OUT_ROOT="$SCRATCHPAD/codex"        # session scratchpad, never the repo
mkdir -p "$CODEX_OUT_ROOT/<slug>"
# write the task book to $CODEX_OUT_ROOT/<slug>/task.md, then:
.claude/skills/dispatch-codex/dispatch.sh <slug>

dispatch.sh supplies --sandbox workspace-write, --json (events to events.jsonl), -o last-message.txt, --ignore-rules, the MCP/plugin emptying, the env-var scrub, the env-file stash, a timeout (default 2700 s, CODEX_TIMEOUT to change), and afterwards prints token usage, the suspect-string audit and git status --porcelain. Extra arguments pass through to codex exec — that is where a per-task model or effort override goes:

-c values parse as TOML — strings need their own quotes inside the shell quotes. Never pass --approve-for-me or --dangerously-bypass-*: exec's auto-deny of escalation is what makes the sandbox the fence. Never run two dispatches (codex or grok) concurrently over overlapping paths.

A follow-up fix can resume the same thread with its context intact: codex exec resume --last (plus the same fences — run it through your own judgment, there is no wrapper for it yet).

3. Reading the result

1. dispatch.sh prints exit= tokens= commands= out=; nonzero exit tails stderr.log, 124 is the timeout.
2. A clean exit is not acceptance. Read report.md in the output directory — the task book requires one — then run the gates yourself.
3. last-message.txt is the executor's closing paragraph; events.jsonl is the full record, one JSON line per event, every command with its aggregated_output. The audit section of the dispatch output points into it.
4. git status --porcelain (printed at the end) is acceptance check one: exactly the task book's writable paths, nothing else. The report lives in the scratchpad, so the status is a pure signal.

4. The task book

Template: task-book-template.md in this directory. Everything from dispatch-grok §4 holds (English, self-contained, no open design decisions, acceptance criteria the orchestrator runs, fixed report path and structure, forbid ranking, demand a positive control on any audit) with the environment section swapped: codex has a sandboxed shell and no network, the repo's env files do not exist during the run, and reads outside the repo are forbidden by the book and audited rather than denied by policy.

CLAUDE.md is auto-loaded — do not re-paste the iron rules; restate the specific ones the task turns on. A task touching apps/web almost always turns on iron rules 1 (no background gradients — the sanctioned exceptions are annotated in-code), 2 (KunUI first, never modify KunUI) and 11 (single real root element per page).

5. What the orchestrator never delegates

Identical in shape to dispatch-grok §5, and it does not soften because the executor can run a compiler: adjudications and scope calls; every gate; every migration under apps/api/migrations/** and every schema decision behind one (plus the end-of-task migration reminder to the user — that duty is the orchestrator's); everything that touches the database, production, or a live upstream (catalog / OAuth / community / image / trust) with real keys; all git; any ruling under iron rule 1 (whether a gradient is sanctioned) or iron rule 2 (whether a KunUI equivalent exists — an executor never hand-rolls around KunUI and never edits KunUI itself); and final acceptance.

6. Choosing between codex and grok

Both are third-party executors with the same shape of fence and the same task-book contract. Measured differences that matter when picking:

• codex can self-check a build offline; grok cannot run anything. For apps/web work this weighs heavily: a Vue/TS change never passed through vue-tsc is expensive to accept, and only codex can run it.
• codex cannot touch .git/ or anything outside the repo, enforced by kernel sandbox; grok's only hard fence is its deny rules.
• grok can read the env files only through a deny-rule gap; codex would read them freely — hence the stash. Neither executor is ever handed a secret on purpose.
• Cost order of magnitude (sibling-repo probe, 2026-09-04): 18 commands ≈ 138k in / 4.7k out tokens through the gateway.

When in doubt, dispatch the one whose failure mode you can check more cheaply, and never both onto overlapping paths at once.