use-cases/github-code-reviews.md Codex Docs, 2026-02-19 20:37 UTC → 2026-04-07 00:40 UTC

1# Review pull requests faster | Codex use cases

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3[← All use cases](https://developers.openai.com/codex/use-cases)

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5Use Codex in GitHub to automatically surface regressions, missing tests, and documentation issues directly on a pull request.

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7Easy

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95s

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11Related links

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13[Use Codex in GitHub](https://developers.openai.com/codex/integrations/github) [Custom instructions with AGENTS.md](https://developers.openai.com/codex/guides/agents-md)

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15## Best for

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17 - Teams that want another review signal before human merge approval

18 - Large codebases for projects in production

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20## Skills & Plugins

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22- [Security Best Practices](https://github.com/openai/skills/tree/main/skills/.curated/security-best-practices)

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24 Focus the review on risky surfaces such as secrets, auth, and dependency changes.

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26## Starter prompt

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28@codex review for security regressions, missing tests, and risky behavior changes.

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30## How to use

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32Start by adding Codex code review to your GitHub organization or repository. See [Use Codex in GitHub](https://developers.openai.com/codex/integrations/github) for more details.

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34You can set up Codex to automatically review every pull request, or you can request a review with `@codex review` in a pull request comment.

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36If 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`.

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38This will start a new cloud task that will fix the issue and update the pull request.

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40## Define additional guidance

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42To customize what Codex reviews, add or update a top-level `AGENTS.md` with a section like this:

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44```md

45## Review guidelines

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47- Flag typos and grammar issues as P0 issues.

48- Flag potential missing documentation as P1 issues.

49- Flag missing tests as P1 issues.

50 ...

51```

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53Codex 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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55## Related use cases

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57[![](/images/codex/codex-wallpaper-1.webp)

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59### Bring your app to ChatGPT

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61Build one narrow ChatGPT app outcome end to end: define the tools, scaffold the MCP server...

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63Integrations Code](https://developers.openai.com/codex/use-cases/chatgpt-apps)[![](/images/codex/codex-wallpaper-3.webp)

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65### Generate slide decks

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67Use Codex to update existing presentations or build new decks by editing slides directly...

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69Data Workflow](https://developers.openai.com/codex/use-cases/generate-slide-decks)[![](/images/codex/codex-wallpaper-2.webp)

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71### Kick off coding tasks from Slack

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73Mention `@Codex` in Slack to start a task tied to the right repo and environment, then...

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75Integrations Workflow](https://developers.openai.com/codex/use-cases/slack-coding-tasks)