Using API Pipe "Response Validation" to halt execution of Automation task

I’ve written a Pipe that makes an API call with a date filter. The response is always valid, but may or may not contain a record.
I want the Pipe execution to terminate for records where the API doesn’t return a single record, and only perform the Pip record update step where the API is successful.
I expected the Pipe “Response Validation” rules to achieve this, but it doesn’t seem to make a difference. What am I missing?