Fail - AWS Step Functions


A Fail state ("Type": "Fail") stops the execution of the state machine and marks it as a failure, unless it is caught by a Catch block.

The Fail state only allows the use of Type and Comment fields from the set of common state fields. In addition, the Fail state allows the following fields.

Cause (Optional)

A custom failure string that you can specify for operational or diagnostic purposes.

Error (Optional)

An error name that you can provide for operational or diagnostic purposes.


You cannot specify values for the Cause and Error fields by appending .$ to these fields, such as Cause.$ and Error.$.

Because Fail states always exit the state machine, they have no Next field and don't require an End field.

The following is an example.

"FailState": { "Type": "Fail", "Cause": "Invalid response.", "Error": "ErrorA" }