AJAX request returns 200OK but fails despite return data being JSON

Question

Edit: In my case, The the reason that it was not returning to correct information is that I was trying to use JSONP to connect to a CORS data setup, wherea

Answer 1

The response is:

Content-Type:application/json
["Asset","AssetElementDefMap",…,"WorkingSet"]

That's no JSONP script, but plain JSON (the "padding", ie. the callback function, is missing). Since the request is cross-domain, you're not allowed to access it - and executing it as a script fails even when the resource loads with a 200 OK status.