Codex Plugin for Claude Code
I use Codex for adversarial review inside Claude Code because Opus and Sonnet aren't great at grading their own output, an independent second model (OpenAI) challenges design decisions and reveals blind spots invisible in self-review.
Strengths
- Cross-model adversarial review, Codex challenges Claude on ITS own decisions, detects blind spots
- Official OpenAI, with `/codex:review`, `/codex:adversarial-review`, and `/codex:rescue` to hand it an investigation or a fix outright
- Reuses existing Codex CLI auth (~/.codex/config.toml), no extra account needed
- Background mode: delegates a review in the background while you keep coding
- Native review gate (`/codex:setup --enable-review-gate`): an end-of-turn hook has Codex review and blocks the response while it flags an issue. It is the version of the "have Codex review everything" rule people write into CLAUDE.md that actually holds, because it blocks instead of reminding
Limitations
- Requires a ChatGPT subscription (Free included) or an OpenAI API key, plus Node.js 18.18 or later
- Higher latency than a local review, network call to OpenAI API
- API cost if not using ChatGPT free tier, monitor on large projects
- The review gate can chain a long Claude and Codex loop and drain your quotas: OpenAI keeps it for sessions you are watching. Reviewing every line, as a circulating reel advises ([Instagram reel DdcEVXsq6l3](https://www.instagram.com/reel/DdcEVXsq6l3/)), means paying two models for a comma: the right grain is the finished change, or the commit
Best for
- Critical review phases where you want an independent second opinion from Claude, architecture, security, design choices
- High-stakes projects where Claude self-review is insufficient, audit before merging to main
- Irreversible decisions (DB migration, API contract refactor, stack choice) where a second model challenges the logic before the code ships