Codex CLI as a Subagent

When to Use

• Use when a bounded coding, review, or verification task can run in a separate Codex CLI session.
• Use when parallel work needs explicit file ownership and a clear definition of done.

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. Confirm the user's intended authentication mode and account; this workflow assumes ChatGPT login and must not silently switch to billable API-key authentication.

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.