Loop block fails to iterate over JSON array from Data Action

Architect & Flows
1

I can’t seem to figure out why the Loop block returns empty results when iterating over a JSON array returned from a Data Action. My Data Action returns a valid list of objects.

“The Loop block iterates over an array returned by the previous step.”

Here is my payload structure:

{"items": [{"id": 1}, {"id": 2}]}

I map the output to items. The loop executes once with null values instead of two iterations. Am I missing a schema definition in the Data Action response?