On the one hand, mutation testing is an important concept that more people should know about and use.
On the other, I fail to see how AI is helpful here, as mutation testing is an issue completely solvable by algorithms.
The need to use external LLMs like OpenAI is also a big no from me.
I think I'll stick to Pitest for my Java code.
Regarding mutation testing, you don't write any "tests for your test". Rather, a mutation testing tool automatically modifies ("mutates") your production code to see if the modification will be caught by any of your tests.
That way you can see how well your tests are written and how well-tested parts of your application are in general. Its extremely useful.