> ## 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.

# Create Definition

Create a new workflow or playground definition.

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

### Request Body

| Parameter  | Type   | Required | Description                                   |
| :--------- | :----- | :------- | :-------------------------------------------- |
| `engine`   | string | Yes      | Must be `workflow_blobhub`.                   |
| `command`  | string | Yes      | Must be `create_definition`.                  |
| `alias`    | string | Yes      | Unique alias for the definition (6-42 chars). |
| `category` | string | Yes      | `workflow` or `playground`.                   |

### Response

| Parameter    | Type   | Description                    |
| :----------- | :----- | :----------------------------- |
| `definition` | object | The created definition object. |

### Example

<CodeGroup>
  ```json Request theme={null}
  {
    "engine": "workflow_blobhub",
    "command": "create_definition",
    "alias": "data-process",
    "category": "workflow"
  }
  ```

  ```json Response theme={null}
  {
    "definition": {
      "id": "def_001",
      "alias": "data-process",
      "category": "workflow"
    }
  }
  ```
</CodeGroup>