In my experience Claude tends to immensely over complicate things and go for a complex abstraction scheme even when all it needs to do is two lines of code. Combined with its eagerness to just code and more importantly pay more attention to the last prompt causes it to do an insanely complex solution first and then patch things with half assed attempts. The whole ordeal results in a code that on an initial glance looks okay, but quickly breaks down and becomes unmanageable. A significant effort is needed to push back Claude’s tendencies, so I mainly find myself pushing back or looking for ways to write an initial prompt with enough guidance, but only Fable was following them properly, Opus simply acts like a rhino in a china shop.