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

# Runner.register

```python theme={"system"}
def Runner.register(task: type[Task]) -> None
```

Register a task class with a reusable runner definition.

Use `register` when you want to build a runner incrementally instead of passing all task classes to the [`Runner`](/api-reference/python/tilebox.workflows/Runner) constructor.

## Parameters

<ParamField path="task" type="type[Task]" required>
  Task class that this runner can execute.
</ParamField>

## Returns

`None`

<RequestExample>
  ```python Python theme={"system"}
  from tilebox.workflows import Runner

  from my_workflow.tasks import MyRootTask, MySubtask

  runner = Runner()
  runner.register(MyRootTask)
  runner.register(MySubtask)
  ```
</RequestExample>