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# Comment attachment

The Comment Attachment object represents [files](/reference/file-object) that have been attached to a [Comment](/reference/comment-object).

<Note>
Comments can currently support up to 3 attachments.
</Note>

## Request format (input)

### Object properties

After following the [Working with files and media](/docs/working-with-files-and-media) guide, provide an array of objects under the `attachments` parameter in the [Create comment](/reference/create-a-comment) API, each containing the following properties:

| Parameter | Type | Description | Example value |
| :--- | :--- | :--- | :--- |
| `file_upload_id` | `string` (UUID) | ID of a [File Upload](/reference/file-upload) with a status of `"uploaded"` | `"2e2cdb8b-9897-4a6c-a935-82922b1cfb87"` |
| `type` | `string`  (optional) | Possible type values are:`"file_upload"` | `"file_upload"` |


Example Create Comment request:

**`API request`**

```json API request
{
  "parent": {
    "page_id": "d0a1ffaf-a4d8-4acf-a1ed-abae6e110418"
  },
  "rich_text": [
    {
      "text": {"content": "Thanks for the helpful page!"}
    },
  ],
  "attachments": {
    "file_upload_id": "2e2cdb8b-9897-4a6c-a935-82922b1cfb87"
  }
}
```

In the Notion app, when viewing a comment uploaded using the API, the user experience is automatically customized based on the detected category of the file upload. For example, uploading a `.png` file displays your attachment as an inline image instead of a regular file download block.

## Response format (output)

### Object properties

The response of Comment APIs like [Create comment](/reference/create-a-comment) contains `attachments` with the following fields:

| Field      | Type            | Description                                                                                                                                 | Example value                                                                                          |
| :--------- | :-------------- | :------------------------------------------------------------------------------------------------------------------------------------------ | :----------------------------------------------------------------------------------------------------- |
| `category` | `string` (enum) | The category of this attachment. Possible type values are: `"audio"`, `"image"`, `"pdf"`, `"productivity"`, and `"video"`                   | `"audio"`                                                                                              |
| `file`     | `object`        | A [file object](/reference/file-object#notion-hosted-files-type-file)  containing type-specific configuration. | `{"url": "https://s3.us-west-2.amazonaws.com/...",       "expiry_time": "2025-06-10T21:26:03.070Z"}` |

Example attachment object in Create Comment response:

**`Comment Attachment Response`**

```json Comment Attachment Response
{
  "category": "video",
  "file": {
    "url": "https://s3.us-west-2.amazonaws.com/...",
    "expiry_time": "2025-06-10T21:26:03.070Z"
  }
}
```

The `file.url` is a temporary download link generated at the time of retrieving a comment. See the guide on [Retrieving existing files](/docs/retrieving-files) to learn more about accessing the files you upload.