Because most APIs return JSON, you need to get the object from JSON (from the green “response” block) rather than trying to generate JSON from the object (it’s not an object).
Also, the “ParsedResults” or “ParsedText” value may be empty (null). In fact, the sample URL in their documentation just returned a null ParsedResults value for me (“Timed out waiting for results”).
You’re going to have to consider what types of responses you might get – including error messages from the API – and plan your blocks accordingly.
If you go to the 17:43 mark in my tutorial video, you’ll see how I use the “get object from JSON” block.