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

# Update Definition

Update the alias of a definition.

## **POST** `/revisions/:id/data/command` (Command: `update_definition`)

### Request Body

| Parameter       | Type   | Required | Description                  |
| :-------------- | :----- | :------- | :--------------------------- |
| `engine`        | string | Yes      | Must be `workflow_blobhub`.  |
| `command`       | string | Yes      | Must be `update_definition`. |
| `definition_id` | string | Yes      | The ID of the definition.    |
| `alias`         | string | Yes      | New unique alias.            |

### Response

Returns an empty JSON object upon success.

### Example

<CodeGroup>
  ```json Request theme={null}
  {
    "engine": "workflow_blobhub",
    "command": "update_definition",
    "definition_id": "def_001",
    "alias": "new-process-name"
  }
  ```

  ```json Response theme={null}
  {}
  ```
</CodeGroup>