# Asynchronous Activity completion - Ruby SDK

> Asynchronously complete an Activity in Temporal using the Ruby SDK. Follow simple steps to allow an Activity Function to return without the Activity Execution completing.

## How to asynchronously complete an Activity 

This page describes how to asynchronously complete an Activity.

[Asynchronous Activity Completion](/activity-execution#asynchronous-activity-completion) enables the Activity Function to return without the Activity Execution completing.

There are three steps to follow:

1. The Activity provides the external system with identifying information needed to complete the Activity Execution.
   Identifying information can be a [Task Token](/activity-execution#task-token), or a combination of Namespace, Workflow Id, and Activity Id.
2. The Activity Function completes in a way that identifies it as waiting to be completed by an external system.
3. The Temporal Client is used to Heartbeat and complete the Activity.

To mark an Activity as completing asynchronously, do the following inside the Activity.

```ruby
# Capture token for later completion
captured_token = Temporalio::Activity::Context.current.info.task_token

# Raise a special exception that says an activity will be completed somewhere else
raise Temporalio::Activity::CompleteAsyncError
```

To update an Activity outside the Activity, use the [async_activity_handle](https://ruby.temporal.io/Temporalio/Client.html#async_activity_handle-instance_method) method on the client to get the handle of the Activity.

```ruby
handle = my_client.async_activity_handle(captured_token)
```

Then, on that handle, you can use `heartbeat`, `complete`, `fail`, or `report_cancellation` methods to update the Activity.

```ruby
handle.complete('completion value')
```