> For the complete documentation index, see [llms.txt](https://atlas.anywhere.now/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://atlas.anywhere.now/developer-docs/generic-dialogue-provider/attachments.md).

# Generic Dialogue Provider API attachments

Upload, download, and delete Generic Dialogue Provider message attachments.

Use these endpoints to manage message attachments. For shared path parameters and error behavior, see [Messages, dialogues, and attachments](/developer-docs/generic-dialogue-provider/messages-and-dialogues.md).

## POST /api/v1/message/{messageId}/attachment

Upload an attachment for a message.

Attachments are current API functionality. Availability can depend on the Generic Dialogue Provider attachment feature configuration.

### URL parameters

| Parameter   | Type   | Required | Description                |
| ----------- | ------ | -------- | -------------------------- |
| `messageId` | string | Yes      | Message ID in GUID format. |

### Request body

Send `multipart/form-data` with a `file` part.

| Field  | Type | Required | Description                                   |
| ------ | ---- | -------- | --------------------------------------------- |
| `file` | file | Yes      | Attachment file. The file size cannot be `0`. |

### Response

#### Success: 201 Created

```json
{
  "id": "8f14b9a5-bb29-4af6-9f28-8f8f4e1f5a5a"
}
```

| Field | Type   | Description            |
| ----- | ------ | ---------------------- |
| `id`  | string | Created attachment ID. |

#### Error responses

| Status                      | Description                                                                                                          |
| --------------------------- | -------------------------------------------------------------------------------------------------------------------- |
| `400 Bad Request`           | `messageId` is not in GUID format, the file is missing, or the file size is `0`.                                     |
| `401 Unauthorized`          | The bearer token is missing or invalid.                                                                              |
| `404 Not Found`             | The message could not be found.                                                                                      |
| `409 Conflict`              | Generic Dialogue Provider settings are not available or the attachment cannot be added in the current message state. |
| `500 Internal Server Error` | The service could not process the request.                                                                           |

### Example

```bash
curl -X POST "<base-url>/api/v1/message/3657e938-d1ae-42f6-8b89-75e5e39f1be9/attachment" \
  -H "Authorization: Bearer <access-token>" \
  -F "file=@screenshot.png;type=image/png"
```

## GET /api/v1/message/{messageId}/attachment/{attachmentId}

Download an attachment.

### URL parameters

| Parameter      | Type   | Required | Description                   |
| -------------- | ------ | -------- | ----------------------------- |
| `messageId`    | string | Yes      | Message ID in GUID format.    |
| `attachmentId` | string | Yes      | Attachment ID in GUID format. |

### Response

#### Success: 200 OK

The endpoint returns the attachment file content. Successful responses can use `application/octet-stream`; error responses can use JSON.

#### Error responses

| Status                      | Description                                           |
| --------------------------- | ----------------------------------------------------- |
| `400 Bad Request`           | `messageId` or `attachmentId` is not in GUID format.  |
| `401 Unauthorized`          | The bearer token is missing or invalid.               |
| `404 Not Found`             | The message or attachment could not be found.         |
| `409 Conflict`              | Generic Dialogue Provider settings are not available. |
| `500 Internal Server Error` | The service could not process the request.            |

## DELETE /api/v1/message/{messageId}/attachment/{attachmentId}

Delete an attachment.

### URL parameters

| Parameter      | Type   | Required | Description                   |
| -------------- | ------ | -------- | ----------------------------- |
| `messageId`    | string | Yes      | Message ID in GUID format.    |
| `attachmentId` | string | Yes      | Attachment ID in GUID format. |

### Response

#### Success: 204 No Content

The attachment is deleted. The response body is empty.

#### Error responses

| Status                      | Description                                                                                                            |
| --------------------------- | ---------------------------------------------------------------------------------------------------------------------- |
| `400 Bad Request`           | `messageId` or `attachmentId` is not in GUID format.                                                                   |
| `401 Unauthorized`          | The bearer token is missing or invalid.                                                                                |
| `404 Not Found`             | The message or attachment could not be found.                                                                          |
| `409 Conflict`              | Generic Dialogue Provider settings are not available or the attachment cannot be deleted in the current message state. |
| `500 Internal Server Error` | The service could not process the request.                                                                             |

## Related topics

* [Messages, dialogues, and attachments](/developer-docs/generic-dialogue-provider/messages-and-dialogues.md)
* [Messages](/developer-docs/generic-dialogue-provider/messages.md)
* [Dialogues](/developer-docs/generic-dialogue-provider/dialogues.md)
* [Authentication](/developer-docs/generic-dialogue-provider/authentication.md)
* [Event subscriptions and callbacks](/developer-docs/generic-dialogue-provider/events.md)


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