---
title: Comment
description: Post a comment on a pull request.
---

The `comment` action allows Mergify to post a comment on your pull request when
certain conditions are met.

The comment action can provide automated responses to events in your pull
request workflow, based on the conditions and message you customize.

## Parameters

| Key name | Value type | Default | Description |
| --- | --- | --- | --- |
| `bot_account` | simple-template or null | `null` | Mergify can impersonate a GitHub user to comment a pull request. If no `bot_account` is set, Mergify will comment the pull request itself. |
| `message` | simple-template or null | `null` | The message to write as a comment. |

## Examples

### Needs Review

In this example, Mergify will post the message "Thank you for your
contribution! A reviewer will be assigned soon." when a pull request is labeled
with "needs review".

```yaml
pull_request_rules:
  - name: comment when a pull request is labeled "needs review"
    conditions:
      - label = needs review
    actions:
      comment:
        message: Thank you for your contribution! A reviewer will be assigned soon.
```

### Warn of Conflicting Pull Requests

When a pull request is in conflict and cannot be merged, it's nice to be
notified automatically by Mergify. You can do this using this rule:

```yaml
pull_request_rules:
  - name: comment when a pull request is in conflict
    conditions:
      - conflict
    actions:
      comment:
        message: "@{{author}} Your PR is in conflict and cannot be merged."
```

### Merge Thank You

In this example, Mergify will post the message "Thank you for your
contribution! Your pull request has been merged." when a pull request is
merged.

```yaml
pull_request_rules:
  - name: comment when a pull request is merged
    conditions:
      - merged
    actions:
      comment:
        message: Thank you for your contribution @{{author}}! Your pull request has been merged.
```