Review pull requests faster | Codex use cases

Codex use cases

Codex use case

Review pull requests faster

Catch regressions and potential issues before human review.

Difficulty Easy

Time horizon 5s

Use Codex 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

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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

• Security Best Practices

  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.

@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.

Related use cases

[

Deploy an app or website

Use Codex with Build Web Apps and Vercel to turn a repo, screenshot, design, or rough app...

Front-end Integrations](https://developers.openai.com/codex/use-cases/deploy-app-or-website)[

Bring your app to ChatGPT

Build one narrow ChatGPT app outcome end to end: define the tools, scaffold the MCP server...

Integrations Code](https://developers.openai.com/codex/use-cases/chatgpt-apps)[

Complete tasks from messages

Use Computer Use to read one Messages thread, complete the task, and draft a reply.

Knowledge Work Integrations](https://developers.openai.com/codex/use-cases/complete-tasks-from-messages)