Review pull requests faster | Codex use cases
Use Codex in GitHub to automatically surface regressions, missing tests, and documentation issues directly on a pull request.
Easy
5s
Related links
Use Codex in GitHub Custom instructions with AGENTS.md
Best for
- Teams that want another review signal before human merge approval
- Large codebases for projects in production
Skills & Plugins
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Focus the review on risky surfaces such as secrets, auth, and dependency changes.
Starter prompt
@codex review for security regressions, missing tests, and risky behavior changes.
How to use
Start by adding Codex code review to your GitHub organization or repository. See Use Codex 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 task that will fix the issue and update the pull request.
Define additional guidance
To customize what Codex reviews, add or update a top-level AGENTS.md with a section like this:
## Review guidelines
- Flag typos and grammar issues as P0 issues.
- Flag potential missing documentation as P1 issues.
- Flag missing tests as P1 issues.
...
Codex applies guidance from the closest AGENTS.md to each changed file. You can place more specific instructions deeper in the tree when particular packages need extra scrutiny.
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