| name | codex |
| description | Invoke Codex CLI as a sub-agent for code tasks. Useful for second opinions, parallel exploration, or offloading isolated subtasks. |
| version | 1.0.0 |
Basic invocation
Pipe the prompt on stdin; use exec for non-interactive output:
echo "<prompt>" | codex exec --skip-git-repo-check
--skip-git-repo-check lets it run outside a git repo. Drop it when invoking inside a repo where codex should see git context.
Useful flags
-m <model> — override model (e.g. gpt-5.1-codex).-C <dir> — set working directory.-s read-only — sandbox mode (read-only, workspace-write, danger-full-access).--dangerously-bypass-approvals-and-sandbox — fully autonomous; only inside an already-sandboxed env.-i <file> — attach image(s).--output-schema <file.json> — constrain final response to a JSON schema.
Patterns
Heredoc for multi-line prompts:
codex exec --skip-git-repo-check <<'EOF'
Review foo.rs for race conditions.
Report findings as a bullet list.
EOF
From a file:
codex exec --skip-git-repo-check < prompt.txt
Inside a repo, read-only second opinion:
echo "Audit auth.rs for input validation gaps." | codex exec -s read-only
Notes
- Output goes to stdout; redirect or pipe as needed.
- Long runs: launch via Bash
run_in_background and read output later.
- Prompt is self-contained — codex has no access to this conversation.
