I’ve read somewhere, IIRC, that you moslty need to test three things: Correct input, incorrect input, and input that are on the fence between the two. By doing some intersection stuff (with the set of parameters, behavior that are library dependent), you mostly have a few things left to test. And the actual process of deciding on which case to test is actually important as that is how you highlight edge cases and incorrect assumptions.

Also writing test cases is how you experience the pain of having things that should not be coupled together. So you can go refactor stuff instead of having to initialize the majority of your software.

If you need to hand write tests to think through all that then sure, don’t let an AI do it for you.