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 (3,700 ⭐), actively maintained, `/codex:review` and `/codex:adversarial-review` commands
- Reuses existing Codex CLI auth (~/.codex/config.toml), no extra account needed
- Background mode: delegates a review in the background while you keep coding
Limitations
- Requires Codex CLI installed + ChatGPT free or OpenAI API key, double prerequisite
- Higher latency than a local review, network call to OpenAI API
- API cost if not using ChatGPT free tier, monitor on large projects
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