> ## Documentation Index
> Fetch the complete documentation index at: https://ona.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Mention Ona on a pull request

> Mention @ona-agent in a GitHub pull request comment to start an Ona agent on the PR.

<Note>Available on the Core plan. [Contact sales](https://ona.com/contact/sales) to enable it for Enterprise.</Note>

Mention `@ona-agent` in a pull request comment to start an Ona agent on that PR. The agent reads the PR diff and recent comments, then works on the task you describe.

For installation, see [GitHub App](/ona/integrations/configure-github).

## How it works

* The agent runs under **your identity**, mapped from your linked GitHub login. It uses your organization role and project permissions. Commits and PRs the agent opens are attributed to you.
* The Ona GitHub App posts the reactions and reply comments. Your account needs no extra permissions for that.
* The agent sees the PR title, body, diff, and recent comments. Its access to the rest of the repository is governed by the [project](/ona/projects/overview) at runtime.
* Pull requests from forks are ignored. Fork PRs can carry untrusted code, and anyone with a GitHub account can comment on them.
* Per-organization rate limits apply.

## Prerequisites

* The [Ona GitHub App](/ona/integrations/configure-github) is installed on the GitHub organization that owns the repository.
* The repository is in the App's selected repositories.
* An Ona [project](/ona/projects/overview) exists for the repository. If one does not, the agent prompts you to create one.

## Where you can mention

The agent responds to mentions in three places on a pull request:

| Surface                   | Where it appears                                                                                               |
| ------------------------- | -------------------------------------------------------------------------------------------------------------- |
| **PR comment**            | The main conversation tab. Triggered by `issue_comment` events.                                                |
| **Inline review comment** | A comment attached to a specific line in the diff. Triggered by `pull_request_review_comment` events.          |
| **Review submission**     | The body of a submitted review (Approve, Request changes, Comment). Triggered by `pull_request_review` events. |

Mentions in regular issues and on fork PRs are ignored.

## Supported handles

Use `@ona-agent` to trigger the agent.

Mentions inside fenced code blocks, inline code spans, blockquotes, HTML comments, and image syntax are ignored, so you can write about the handle without triggering it.

## Examples

### Request a code review

A comment with only the handle starts a review:

```
@ona-agent
```

The agent runs with the prompt `Review this PR and help with any issues.`

### Mention with a task

Anything after the handle becomes the agent's prompt:

```
@ona-agent please add unit tests for the new pricing function
```

```
@ona-agent the snapshot test on line 42 is failing, figure out why and fix it
```

### Reply on a review thread

If you mention the agent in a reply to an inline review comment, the agent receives the surrounding thread as context.

## Commands

`@ona-agent retry` replays the last failed agent start on this PR. Use it after fixing the cause (for example, after creating a missing project).

The command must be the whole prompt. `@ona-agent retry the deploy` runs as a normal prompt.

## What you'll see

1. The agent reacts to your comment with an emoji to confirm the trigger.
2. It posts one reply with the running session and a link to the Ona session view.
3. The same reply updates in place as the agent works.

<div className="mux-player-container" data-playback-id="nqquvzkTxHtMusR55kEA4dIt6Uqbrew02ydQnDt15bOg" data-title="Mention @ona-agent on a pull request" data-thumbnail-time="0" />

## Cancelling

To cancel a running session from GitHub:

* **Delete your trigger comment.** Cancels the session and posts a confirmation.
* **Delete the PR's head branch.** Cancels the session.

You can also cancel from the Ona session view.

## Limitations

* The agent reads the PR diff and the most recent comments. Older comments are not included.
* Fork PRs are not supported. See [How it works](#how-it-works).
* Editing a comment after the agent starts does not change the prompt. To change direction, post a new `@ona-agent` comment.
* Posting a second `@ona-agent` mention while the first session is still running is not guaranteed to queue. Wait for the first reply, or cancel the running session by deleting the trigger comment.
* Available on the Core plan. [Contact sales](https://ona.com/contact/sales) to enable it for Enterprise.

## Next steps

* [GitHub App](/ona/integrations/configure-github): install and manage the App.
* [Projects](/ona/projects/overview): required so the agent knows where to run.
* [Integrations overview](/ona/integrations/overview).

## Troubleshooting

<Accordion title="The agent didn't respond">
  Check, in order:

  1. Is the [Ona GitHub App](/ona/integrations/configure-github) installed on the repository's owner?
  2. Is the repository in the App's selected repositories?
  3. Is your Ona organization on the Core plan?
  4. Did you spell the handle correctly (`@ona-agent`)?
  5. Are you commenting on a **pull request**, not a regular issue?
  6. Is the PR from the same repository, not a fork?

  If all six check out and the agent stays silent for a minute or two, contact support.
</Accordion>

<Accordion title="Missing GitHub permissions">
  The agent posted a `[!CAUTION]` comment because the App is missing a required permission. Ask an admin to update the App install. See [Permissions](/ona/integrations/configure-github#permissions).
</Accordion>

<Accordion title="No project matches this repo">
  No Ona project is configured for this repository. The agent posts a link to create one. Once you create it, the agent resumes the original mention. If you do not create the project within a few minutes, the watcher times out and you'll need to mention the agent again.
</Accordion>