> ## 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.

# Upload Definition Content

Upload/Save the content of a definition.

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

### Request Body

| Parameter       | Type   | Required | Description                      |
| :-------------- | :----- | :------- | :------------------------------- |
| `engine`        | string | Yes      | Must be `workflow_blobhub`.      |
| `command`       | string | Yes      | Must be `upload_definition`.     |
| `definition_id` | string | Yes      | The ID of the definition.        |
| `definition`    | object | Yes      | The JSON body of the definition. |

### Response

Returns an empty JSON object upon success.

### Example

<CodeGroup>
  ```json Request theme={null}
  {
    "engine": "workflow_blobhub",
    "command": "upload_definition",
    "definition_id": "def_001",
    "definition": {
      "steps": [...]
    }
  }
  ```

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