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

# Runtime Variables

> Accessing information about the runtime while running tasks

## Available Runtime Variables

In order to access information about the runtime while running a task, you can use the `context` value.

`context` includes important contextual information about the runtime, like the current `task_id` and `callback_url`.

| Field Name | Purpose |
| - | - |
| `container_id` | Unique identifier for a container |
| `stub_id` | Identifier for a stub |
| `stub_type` | Type of the stub (function, endpoint, task queue, etc) |
| `callback_url` | URL called when the invocation finishes |
| `task_id` | Identifier for the specific task |
| `timeout` | Maximum time allowed for the task to run (seconds) |
| `on_start_value` | Any values returned from the `on_start` function |
| `bind_port` | Port number to bind a service to |
| `python_version` | Version of Python to be used |

## Using a Runtime Variable

Any of the fields above can be accessed on the `context` variable:

```python theme={null}
from beam import task_queue

@task_queue()
def handler(context):
    task_id = context.task_id
    return {}
```


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