Won't it generate tests that prove the correctness of the code instead of the correctness of the application? As in: if my code is doing something wrong and I ask it to write tests for it, it will supply tests that pass on the wrong code instead of finding the problem in my code?

That's what a unit test does.

I use it for the same and usually have to ask it to infer the functionality from the interfaces and class/function descriptions. I then usually have to review the tests for correctness. It's not perfect but it's great for building a 60% outline.

At our company I have to switch between 6 or 7 different languages pretty regularly and I'm always forgetting specifics of how the test frameworks work; having a tool that can translate "intent to test" into the framework methods really has been a boon