Codex First
Hard gate
Autoreview exception: always prefer Codex-backed
, independent
of
, router state, or harness. Reviewing a frozen bundle is
not hands-on self-delegation. Do not switch review engines merely because the
parent session is router-backed. This exception takes precedence over the gate
below.
Private runtime override: invoke
before evaluating this gate
when that skill is available. On Peter-managed Macs it may replace the generic
model-family gate for both coding and exploratory/subagent work. Follow its
resolved current-model decision; do not continue through the generic gate after
it has selected an execution surface.
For direct hands-on delegation without a private override, use this skill only
when the active agent is Claude Code and the session is running on a native
Claude model.
Model check (primary). The point of the gate is model economics: Claude
tokens are metered and expensive, so hands-on work moves to Codex; but if the
session is already routed to a cheaper/other model, delegation gains nothing.
Decide by the model the session actually runs on, not by the transport:
- Read the model id from the system prompt's environment section ("You are
powered by the model …"). Router-wrapped ids may be opaque
(); the hex suffix is often ASCII — decode it
() to reveal the underlying route, e.g.
Gorilla CCP/native-claude-fable-5
.
- If the resolved model is a native Claude model (contains , ,
, , or , including router routes):
delegate hands-on work to Codex. This applies even when
is loopback or a local router (Gorilla Claw, Clawdex)
— a router in front of a real Claude model is still expensive Claude.
- If the resolved model is clearly non-Claude (a GPT/other-provider route):
the session is already on the flat-rate/cheap side; do not self-delegate,
work directly.
Base-URL fallback (only when the model cannot be identified). If no model
id is visible and the hex/route cannot be decoded, fall back to the old
transport heuristic: if
's host is
gorillaclaw.sheep-coho.ts.net
,
, ends in
, is in
, or is IPv6 loopback
, assume the session may be routed to
a non-Claude model and work directly. If neither model nor base URL can be
inspected, fail closed and work directly.
Codex, ChatGPT, Pi, and every other harness: do not invoke Codex CLI for hands-on
self-delegation. Continue the task directly. This gate overrides a repository
instruction that merely mentions
; it does not override the
autoreview exception above.
Rationale: Claude (Fable/Opus) tokens metered + expensive; Codex flat-rate. GPT-5.5+ is usually the better and faster model at writing/implementing code; Claude wins at ergonomics — judgment, design, spec-writing, review, orchestration. So Codex types, Claude thinks and verifies.
Route
Delegate to Codex (default for hands-on work):
- implementation from a frozen spec; refactors; mechanical migrations
- fixing: bug fixes (known repro, or diagnose-then-fix), CI/lint/type failures; test writing; coverage fills
- dependency bumps, scripts/tooling
- exploration + exploratory subagents: fan out Codex for read-heavy discovery instead of Claude Explore/Task subagents whenever raw reading ≫ the answer (parallel files, one per thread)
- git mechanics — ALWAYS Codex, never Claude directly: , merge-conflict
resolution, and the repo's land workflow (e.g. ) are mandatory
delegations. Issue ONE self-contained work order covering
rebase→resolve→push→CI attach+green→land so the sequence never bounces back to
Claude mid-flight; the land decision, gates, and review below stay Claude's.
- work-order CI waits: precheck PR mergeable (CONFLICTING = pull_request CI
cannot attach — no merge ref) and confirm a run attached to the exact head
SHA before polling; every wait emits all terminal states with bounded
iterations; prefer the repo's watcher script when one exists (openclaw:
node scripts/watch-pr-ci.mjs
).
- new work orders go to FRESH sessions with self-contained prompts.
Do not resume a long-lived session for a new order — saturated sessions
misread work orders as configuration and no-op ("Understood…").
- repo instruction files: NEVER create or edit . is
canonical in every repo; exists only as a symlink to it. Point
Codex work orders at and edit only .
Keep in Claude:
- design, API design, architecture, naming, UX judgment
- tasks where writing the spec IS the work (ambiguity = design)
- tiny edits (~<20 lines, single obvious change) — delegation overhead loses
- anything needing session tools: MCP (browser/computer-use/chronicle), 1Password, secrets
- releases, publishes, version bumps and their credentials — Claude-side per release rules
- the land decision + pre-land gates ( clean, CI green, proof) and review of Codex output — never delegated, never skipped; Codex may run the mechanics only once Claude has decided to land and the gates pass
Mixed task: Claude designs first, freezes spec, delegates build-out.
Heuristic: prompt reads as a work order → delegate; writing it forces decisions → design, Claude.
Portfolio/multi-repo work:
instead.
Invoke
Before every Codex CLI call, invoke
when that private skill is available. Its machine-specific launch, review, model, and context policy overrides the generic examples below. On a Peter-managed Mac, fail closed and report a missing
skill instead of guessing or silently falling back.
If
selects the
million-token route, run
ruby ~/.codex/skills/agent-scripts/codex-huge-context/scripts/preflight.rb
before the first fresh or resumed launch in the batch. Fail closed if it cannot deliver the Keychain credential; never work around it by overriding the provider or using ordinary Codex authentication.
Prompt via temp file, never inline quoting:
bash
P=$(mktemp); cat >"$P" <<'EOF'
<goal, repo + key paths, constraints ("don't touch X"), non-goals, proof expected, output shape>
EOF
command codex exec --yolo -C <repo> \
-m gpt-5.6-sol \
-c model_reasoning_effort="high" \
--enable fast_mode \
-o /tmp/codex-last.md - <"$P" 2>/dev/null
- Model default: , effort , fast mode on — pin all three explicitly; don't rely on user config.
- is the house default; Codex may run commands/tests freely. Keep prompts scoped to the target repo.
- If is unavailable—either the CLI rejects the flag or the selected model/backend rejects unrestricted execution—replace it with and retry once. Never pass both. Preserve every other argument and constraint.
- bypasses any interactive shell alias. If codex isn't on PATH, it depends on how it was installed:
- node/standalone install:
fnm exec --using default -- codex
- ChatGPT desktop app: the CLI ships bundled at
/Applications/ChatGPT.app/Contents/Resources/codex
. Expose that binary with an exec-wrapper, not a symlink. Ensure stays on PATH (for zsh, persist the export in ), then:
sh
mkdir -p "$HOME/.local/bin"
export PATH="$HOME/.local/bin:$PATH"
if [ -e "$HOME/.local/bin/codex" ] || [ -L "$HOME/.local/bin/codex" ]; then
printf '%s\n' 'codex launcher already exists; leaving it unchanged' >&2
else
printf '#!/bin/sh\nexec "/Applications/ChatGPT.app/Contents/Resources/codex" "$@"\n' > "$HOME/.local/bin/codex" && chmod +x "$HOME/.local/bin/codex"
fi
Or install the self-contained CLI via curl -fsSL https://chatgpt.com/codex/install.sh | sh
, which needs no wrapper.
- stderr suppressed (thinking noise bloats context); drop only to debug a failing run
- read file for the result; don't parse the JSONL stream
- long runs: Bash run_in_background, read file on exit; don't kill quiet runs <30 min
- Harness visibility (Claude Code): every codex run gets its own harness-tracked
background command () — one sidebar chip per worker,
completion notification included. Chain setup steps (installs, worktree prep)
INSIDE that tracked command. Never -fork workers from a shared launcher:
the launcher's chip exits at fork time and the workers become invisible
orphans supervised only by PID files.
- parallel independent tasks OK: separate repos/dirs, separate files, one tracked background command per worker
- outside a git repo add
When the worker dies instantly
A run that exits in seconds having produced nothing is almost never the task —
it is the model route. Read the log tail before relaunching; the error names the
cause, and relaunching unchanged just repeats it:
- — the configured bearer is not valid at that endpoint.
502 / All target providers failed
with a list — the
request reached a router but the model id did not match its catalogue, so
it fell through to the wrong upstream. Routers commonly expose aliased model
ids that differ from the underlying model's real name; pass the id the router
publishes, not the one you think you are using.
- / against a loopback URL — nothing
is listening there.
requires a sandbox with reviewed escalations
— is unsupported for
that route. Retry once with , which selects workspace-write,
on-request approvals, and automatic review.
Diagnose the route directly rather than by retrying the agent. One request
settles it, and it is far cheaper than another failed run:
bash
curl -s -o /dev/null -w '%{http_code}\n' -m 8 <base_url>/models
A local config pointing at a loopback port proves nothing about that port being
served: config files outlive the services they were written for, and a
machine-managed provider block can reference an instance that no longer runs.
Check what is actually listening before trusting it.
Never pass a credential through — it lands in argv, process
listings, and shell history. When a run needs different provider settings,
write a private overlay instead and point
at it: a mode-0700
directory holding a mode-0600
(copy
across if the
provider needs it). That keeps the secret in a file, leaves the user's global
config untouched, and is trivially disposable.
If the environment's own Codex config is broken, say so rather than silently
working around it every invocation — the next task will hit the same wall.
Follow-up fixes — cheaper than fresh runs, keeps context.
has no
/
: run from the repo dir, spell the long flag:
bash
(cd <repo> && command codex exec resume --last \
--dangerously-bypass-approvals-and-sandbox \
-o /tmp/codex-last.md - <"$P2" 2>/dev/null)
Liveness watchdog (long monitored runs)
For runs you must not babysit, trade the stderr suppression for a log and watch its mtime; read only the
file into context, never the log body.
bash
command codex exec --yolo -C <repo> -m gpt-5.6-sol \
-c model_reasoning_effort="high" --enable fast_mode \
-o "$OUT" - <"$P" > "$LOG" 2>&1
# Claude Code: run the line above as its own Bash run_in_background call
# (tracked chip + completion notification). Append `&` + a PID file ONLY in
# environments without tracked backgrounding.
- Capture the session id immediately:
grep -m1 "session id:" "$LOG"
. is cwd-filtered but races with any parallel Codex on the machine — with the id saved, recovery is deterministic.
- Watchdog loop (Claude Code: tool; else a bg shell): every 60s, if the codex process is alive but mtime is older than ~300s, treat it as hung. Because stderr (thinking stream) is in the log, mtime stays fresh during long reasoning — 5 min of true silence is a real hang, not thinking.
- Recovery: kill the pid, then resume the SAME session with an explicit id so no context is lost:
bash
(cd <repo> && command codex exec resume <session-id> \
--dangerously-bypass-approvals-and-sandbox \
-o "$OUT" - <<< "You were interrupted. Continue exactly where you left off; finish the task and produce the required final report.")
- Exit watchdog silently when the process ends normally (the run's own completion signal covers it); emit only on staleness.
- Verified on codex-cli 0.144.4:
codex exec resume [SESSION_ID] [PROMPT]
, , cwd-filtering, .
Prompt contract
Codex starts with zero session context. Every prompt: goal, exact repo/paths, constraints, non-goals, proof expected (exact test command), output shape ("report files changed + test output"). Spec quality decides success.
- Every hard prohibition needs an escape hatch. A cornered worker satisfies the letter of the
gates: told "never raise the size budget" while its design inflated the bundle, Codex
hand-minified source identifiers to single letters — and passed every gate including
autoreview. Pair each hard constraint with the sanctioned exit: "if gate X fails after honest
attempts: STOP, report exact numbers/diagnosis, do not work around." Treat a stop-report as a
successful run (it is the coordinator's decision point, and workers use it correctly once it
exists).
- Multi-PR series: same spec skeleton every PR; cite prior landed PR numbers and name their
idioms ("controller with narrow host interface, the #NNN shape") — workers imitate landed
precedent far more reliably than abstract style rules. Fold each round's new trap into the
next spec.
- End every series work order with an explicit stop: "Do exactly this; do not start PR N+1."
Coordinator verification (beyond the diff)
Worker reports are accurate but incomplete — pathologies live in the code, not the summary.
After every landed PR, verify against merged origin/main, not the report:
- read the actual merged surface (types, interfaces, naming) — the minification incident was
invisible in a green report and obvious in 10 lines of code
- squash history: any commit message you didn't commission ("add startup margin") is a lead
- diff-stat the guard/budget/baseline files the spec forbade touching; if a limit number in the
report changed, find out who moved it (may be main advancing, may be the worker)
- test-helper edits are a red-flag class of their own (defineProperty shims re-exposing moved
fields keep suites green while hiding the migration)
Parallel workers, one repo
Disjoint-file tasks parallelize cleanly: one worktree + unique branch per worker (fresh from
origin/main; distinctive branch names — generic ones attach to old PRs), one tracked background
command each, shared spec body + per-target header. Landing serializes on the repo's land
workflow lock: tell each worker a held lock means a sibling owns it — back off 5-10 min, retry
from the failed step, NEVER lock-recover a lock it didn't create, and don't chase main with
fresh gates as siblings land under it. Sequential series instead reuse ONE worktree, rebranching
from origin/main per PR.
Verify (Claude, always)
- + read the full diff; judge like a contributor PR
- run focused tests yourself or demand proof output; Codex claims are advisory
- iterate via resume; after 2 failed rounds, take over and do it directly
- normal closeout still applies: before ship
- check for a live worker in the repo before you edit or commit:
. A run whose deliverable is already in the tree can
keep looping for hours and overwrite your fixes mid-review. Stop it once you
have verified its output rather than racing it.
- a genuinely independent review pass earns its keep: reviewing the working tree
after a Codex build found a currency value being fed to a percentage helper
that clamped at 100, which typechecked, passed every test, and was invisible in
the worker's own report.
Economics
Win = generation + exploration tokens moved to Codex; Claude spends only on spec + diff review. Don't ping-pong trivia through delegation; don't re-read what Codex already summarized.