Review the code. Hell, maybe even write some code yourself.
What you're describing is how I feel whenever I use an LLM for anything more than the most basic of tasks. I've gone from being a senior level software developer to managing a barely competent junior developer who's only redeeming skill is the ability to type really, really quickly. I quit the management track some time ago because I hated doing all my software development via the medium of design documents which would then be badly implemented by people who didn't care, there's no way you're going to get me to volunteer for that.