Codex CLI as a Subagent

Codex CLI is OpenAI's terminal coding agent. codex exec runs it non-interactively: it works autonomously in a sandbox, streams progress to stderr, and prints only the final message to stdout. Auth reuses the user's ChatGPT subscription — never an API key.

When to delegate

• Self-contained coding task with clear success criteria (fix, feature, refactor, review).
• Parallel work: several independent tasks at once (see Parallel runs).
• Second opinion / independent verification of your own changes.

Do NOT delegate tasks that need conversation context you can't fully write into the prompt.

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