Codex use case
Review GitHub pull requests
Catch regressions and potential issues before human review.
Use Codex code review in GitHub to automatically surface regressions, missing tests, and documentation issues directly on a pull request.
Best for
- Teams that want another review signal before human merge approval
- Large codebases for projects in production
Contents
Review GitHub pull requests
Catch regressions and potential issues before human review.
Use Codex code review in GitHub to automatically surface regressions, missing tests, and documentation issues directly on a pull request.
Use Codex code review in GitHub to automatically surface regressions, missing tests, and documentation issues directly on a pull request.
Best for
- Teams that want another review signal before human merge approval
- Large codebases for projects in production
Skills & Plugins
- Focus the review on risky surfaces such as secrets, auth, and dependency changes.
| Skill | Why use it |
|---|---|
| Security Best Practices | Focus the review on risky surfaces such as secrets, auth, and dependency changes. |
Starter prompt
How to use
Start by adding Codex code review to your GitHub organization or repository. See Codex code review in GitHub for more details.
You can set up Codex to automatically review every pull request, or you can request a review with @codex review in a pull request comment.
If Codex flags a regression or potential issue, you can ask it to fix it by commenting on the pull request with a follow-up prompt like @codex fix it.
This will start a new cloud chat that will fix the issue and update the pull request.
Define review guidance
To customize what Codex reviews, add a ## Code Review Rules section to the
AGENTS.md closest to the code the rules govern. For example:
## Code Review Rules
### Experiment cohorts
- Do not filter treatment comparisons on post-exposure behavior, including conversion or retention.
Safe path: build cohorts from assignment or exposure; report conversion as an outcome.Put repository-wide rules in the root AGENTS.md and service-specific rules
in a nested file. Keep rules concise, describe the behavior to flag and any
safe path or exception, and leave formatting and lint checks in CI. See
Customize what Codex reviews
for setup and rule-writing guidance.
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