Codex

Codex is an independent agent on PATH (codex — invoke as command codex if a shell alias shadows it), sharing this working tree and already authenticated. It is a second opinion, not ground truth: verify what it reports, own what it changes. It reads the same skills your repo carries.

Leave Codex's model at its CLI default unless the user asks for a specific one. The default follows the current Codex release; do not pin a dated model ID in this skill. If an explicit override is needed, verify it is current and pass the requested model with -m <model>.

If codex is not installed

When codex is missing from PATH, offer to install it — ask the user for approval first, never install on your own initiative. On yes, follow the current instructions at https://developers.openai.com/codex/cli. First-run authentication is interactive — hand that step to the user. Verify with codex --version before proceeding.