...
If the step you are referencing returns an array of items, you can specify which item in the array you reference by way of the syntax ‘index.property’. For example, if an API call returns an array of 3 objects, and you want to reference the id of the last one, you would put ‘2‘2.id’ id’ in the ‘property’ field.
If the parameter name or array index provided does not exist in the corresponding return object, null will be used.
...