I've had the same experience. I do a lot of automation of two engineering software packages through python and java APIs which are not terribly well documented and existing discussion of them on the greater web is practically nonexistent.

They are completely, 100% useless, no matter what I do. Add on another layer of abstraction like "give me a function to calculate <engineering value>" and they get even worse. I had a small amount of luck getting it to refactor some really terrible code I wrote while under the gun, but they made tons of errors I had to go back and fix. Luckily I had a pretty comprehensive test suite by that point and finding the mistakes wasn't too hard.

(I've tried all of the "just point them at the documentation" replies I'm sure are coming. It doesn't help)