AWS Step Functions
Developer Guide

OutputPath

OutputPath enables you to select a portion of the state output to pass to the next state. This enables you to filter out unwanted information, and pass only the portion of JSON that you care about.

If you don't specify an OutputPath the default value is $. This passes the entire JSON node (determined by the state input, the task result, and ResultPath) to the next state.

For more information, see: