> For the complete documentation index, see [llms.txt](https://gitbook.com/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://gitbook.com/docs/docs-as-code/git-sync/github-pull-request-preview.md).

# GitHub pull request preview

See a preview of your content when making a pull request in GitHub

When you submit a pull request (PR) to a GitHub branch that has been synced to a GitBook section, you can preview the content before merging. This allows you to check the impact of changes before merging them.

You can use this feature to have a final layer of checks before merging a PR, allowing you to see your changes in a non-production environment before merging it into your synced branch.

### How to access preview links

This behavior works out of the box, provided you have given the [GitBook GitHub app](https://github.com/apps/gitbook-com) the necessary read-only permissions to PRs.

For every PR created using a target branch synced with a GitBook section, you’ll see a status added to the PR with a unique preview URL. Clicking the **Details** link on the status will take you to the preview URL for your content. You can then make sure the content is as expected before merging the PR.

{% hint style="info" %}
Preview links are only accessible by users with a GitBook account.
{% endhint %}

### Security considerations

For security reasons, by default GitBook doesn’t currently generate previews for PRs opened from forks of your repository. Because the content of the PR preview is accessible under your own domain, whether on `.gitbook.io` or your custom domain, a user could generate malicious content in a fork of your public repository and have it served under your name.

We allow users to explicitly configure this through an option in the Git Sync settings.

### FAQ

#### Why can’t I see a preview of my GitBook documentation in my pull request?

Common causes:

* **Your site isn’t published.** PR preview URLs are served from your published docs site (on `.gitbook.io` or your custom domain).
* **Your site is behind authenticated access.** Git Sync PR previews aren’t available for sites published behind [authenticated access](/docs/publish/site-audience/authenticated-access.md).


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation by asking a question.

Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters:

```
GET https://gitbook.com/docs/docs-as-code/git-sync/github-pull-request-preview.md?ask=<question>&goal=<user_goal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.