> ## 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

```python theme={"system"}
class Runner(
    *,
    tasks: list[type[Task]] | None = None,
    cache: JobCache | None = None,
    context: type[RunnerContext] | None = None,
)
```

Define task registrations for a Python workflow project.

A `Runner` object is a reusable definition. Use it for direct execution by connecting it to a [`Client`](/api-reference/python/tilebox.workflows/Client), or reference it from `tilebox.workflow.toml` so release runners can load the same task registrations from a workflow release.

## Parameters

<ParamField path="tasks" type="list[type[Task]] | None">
  A list of task classes this runner can execute.
</ParamField>

<ParamField path="cache" type="JobCache | None">
  Optional [job cache](/workflows/run-and-inspect/caches) used by tasks executed by this runner.
</ParamField>

<ParamField path="context" type="type[RunnerContext] | None">
  Optional runner context class to instantiate for tasks executed by this runner.
</ParamField>

## Example

```python Python theme={"system"}
from tilebox.workflows import Runner
from tilebox.workflows.cache import LocalFileSystemCache

from my_workflow.tasks import MyRootTask, MySubtask


runner = Runner(
    tasks=[MyRootTask, MySubtask],
    cache=LocalFileSystemCache(),
)
```

You can also register tasks after creating a runner:

```python Python theme={"system"}
runner = Runner(cache=LocalFileSystemCache())
runner.register(MyRootTask)
runner.register(MySubtask)
```

Use the same object for direct execution:

```python Python theme={"system"}
from tilebox.workflows import Client

from my_workflow.runner import runner


runner.connect_to(Client(), cluster="dev-cluster").run_forever()
```

Or reference it from `tilebox.workflow.toml` for release execution:

```toml theme={"system"}
[workflow]
slug = "my-workflow"
root = "."
runner = "my_workflow.runner:runner"
```