SendTaskSuccess - AWS Step Functions


Used by activity workers, Task states using the callback pattern, and optionally Task states using the job run pattern to report that the task identified by the taskToken completed successfully.

Request Syntax

{ "output": "string", "taskToken": "string" }

Request Parameters

For information about the parameters that are common to all actions, see Common Parameters.

The request accepts the following data in JSON format.


The JSON output of the task. Length constraints apply to the payload size, and are expressed as bytes in UTF-8 encoding.

Type: String

Length Constraints: Maximum length of 262144.

Required: Yes


The token that represents this task. Task tokens are generated by Step Functions when tasks are assigned to a worker, or in the context object when a workflow enters a task state. See GetActivityTask:taskToken.

Type: String

Length Constraints: Minimum length of 1. Maximum length of 1024.

Required: Yes

Response Elements

If the action is successful, the service sends back an HTTP 200 response with an empty HTTP body.


For information about the errors that are common to all actions, see Common Errors.


The provided JSON output data is not valid.

HTTP Status Code: 400


The provided token is not valid.

HTTP Status Code: 400


The activity does not exist.

HTTP Status Code: 400


The task token has either expired or the task associated with the token has already been closed.

HTTP Status Code: 400

See Also

For more information about using this API in one of the language-specific AWS SDKs, see the following: