Codex GitHub code review is GA: @codex review, auto reviews, and Security Review
After you connect a GitHub repo and enable code review, comment @codex review (or turn on Automatic review) and Codex posts a P0/P1 review that follows AGENTS.md Code Review Rules; research-preview Security Review uses @codex security review. You can then ask @codex fix the P1 issue to push a follow-up fix to the branch when it has permission.