/codex-delegate

name: codex-delegate
description: >-
  Delegate a coding task to the OpenAI Codex CLI as a background implementer, then review its diff and
  land it yourself. Use this whenever the user wants to hand implementation work to Codex — phrasings
  like "have Codex do X", "delegate this to Codex", "run it through Codex", or "use Codex to
  implement/fix/refactor" — or to run a queue of coding tasks through Codex while staying the reviewer.
  Prefer it over a one-shot Codex forwarder (such as the codex-rescue agent) when the user will review
  the diff and commit it themselves. DO NOT USE for tasks small enough to do inline, or when the user
  wants the code written directly without delegating.
license: MIT
compatibility: Requires the `codex` CLI (OpenAI Codex) installed and authenticated, Node 18+, and git. The orchestrating agent must be able to run shell commands and read files. Shell examples assume bash/zsh (macOS/Linux, or Git Bash/WSL on Windows).
metadata:
  version: 0.4.2

Codex Delegate

You are the **orchestrator**. This skill lets you hand a bounded coding task to a separate **implementer** — the OpenAI Codex CLI — then review what it produced and land it yourself. You write the brief and own the judgment; Codex does the typing in its own sandbox; you verify and commit.

Nothing here is specific to one orchestrating agent. The loop needs only the ability to run a shell command and read a file, so it works the same whether you are Claude Code, OpenCode with a selected model, or any comparable agent. (It is designed for and run on Claude Code; treat other orchestrators as designed-for, not yet proven.)

When NOT to use this

• The task is small enough to just do inline — delegation overhead is not worth it.
• The `codex` CLI is not installed or not authenticated (run `codex login`).
• You want to write the code yourself, or you only need a review (use Codex's own `review` command).

Prerequisites (check once)

1. `codex --version` succeeds. If not, install (`npm i -g @openai/codex`) and `codex login`. 2. **Confirm which `codex` is on PATH.** Multiple installs are common (e.g. a current npm/nvm copy and a stale Homebrew one). `command -v codex` shows the active one and `codex --version` its version — an old binary predates flags this skill relies on (`codex exec --json`, `-o`, `exec resume`). The relay also records the version it ran into `result.json`, so a stale binary is visible after the fact. 3. You are in (or will point `--cd` at) the target git repository.

The loop

Run these five steps per task. Steps 1, 4, and 5 are your judgment; 2 and 3 are mechanical.

1. Write the brief

Codex sees **only** the text you send — no repo memory, no chat history, no shared context. Everything the task needs goes in the brief: the goal, the current state, what to change, what to leave untouched, the project's **actual** gate commands (discover them from the repo's CLAUDE.md/AGENTS.md/Makefile — do not assume), and a report contract. Tell Codex it will **not** commit (you will). Keep one task per brief. Full guidance and a template: [references/writing-the-brief.md](references/writing-the-brief.md).

2. Dispatch

Send the brief to Codex with the bundled helper. It wraps `codex exec`, captures the run, and writes a structured `result.json` — so your only job is "run a command, read a file." (`<skill-dir>` below is this skill's installed directory — the folder containing this `SKILL.md`, i.e. the directory you loaded the skill from. Claude Code prints it as "Base directory for this skill" when the skill loads; on other orchestrators use that same directory — if unsure where it landed, run `find ~ -name relay.mjs -path '*codex-delegate*'` and substitute the directory above it.)

node "<skill-dir>/scripts/relay.mjs" --brief brief.txt --cd /path/to/repo
# read-only (review/diagnosis, no edits):   add --read-only
# continue the exact Codex session:         add --session <threadId>  (from result.json; send only the delta brief)
# fallback when no thread id is available:  add --resume-last
# hard time limit (watchdog):               add --timeout 2h  (default: off; implementation runs routinely need 1-2h)
# see all options:                          node .../relay.mjs --help

The helper defaults to a write-capable (`workspace-write`) sandbox and writes its artifacts to a temp dir, so the repo under review stays clean. It **never commits** — see step 5. Mechanics, flags, and the `result.json` shape: [references/dispatch-and-poll.md](references/dispatch-and-poll.md).

3. Wait for completion

The helper blocks until Codex finishes, so back it with whatever your orchestrator offers and resume when it returns:

• **Claude Code:** run the Bash call with `run_in_background: true`; you are notified on completion.
• **Plain shell / other agents:** run it in the foreground for short tasks, or background it and poll

the result file — `… &` in bash/zsh (including Git Bash/WSL), or your shell's equivalent (`Start-Job` in PowerShell, `start /b` in cmd). The run is done when `result.json` exists with a `status`. (A pre-run usage error — bad args or an empty brief — instead exits with code 2 and a stderr message and writes no result file, so check the exit code too. A missing `codex` binary exits 127 but *does* write a `result.json` with status `codex_unavailable`.)

Do not trust progress trackers over reality: a run is finished when `result.json` is written and the process has exited. Read the working tree, not a status line. The implementer's full report is the `finalMessage` field in `result.json` (also printed in full on stdout between the report markers).

4. Review — do not trust the self-report

Codex's `result.json` includes its own summary and gate claims. **Re-verify, don't accept:**

• **Re-run the project's gates yourself** (the test/lint/build commands from step 1). Never take

"gates passed" on faith.

• **Read the diff** against the brief