I've been struggling all week trying to get Claude Code to write code to produce visual (not the usual, verifiable, text on a terminal) output in the form of a SDL_GPU rendered scene consisting of the usual things like shaders, pipelines, buffers, textures and samplers, vertex and index data and so on, and boy it just doesn't seem to know what it's doing. Despite providing paragraphs-long, detailed prompts. Despite describing each uniform and each matrix that needs to be sent. Despite giving it extremely detailed guidance about what order things need to be done in. It would have been faster for me to just write the code myself.

When it fails a couple of times it will try to put logging in place and then confidently tell me things like "The vertex data has been sent to the renderer, therefore the output is correct!" When I suggest it take a screenshot of the output each time to verify correctness, it does, and then declares victory over an entirely incorrect screenshot. When I suggest it write unit tests, it does so, but the tests are worthless and only tests that the incorrect code it wrote is always incorrect in the same ways.

When it fails even more times, it will get into this what I like to call "intern engineer" mode where it just tries random things that I know are not going to work. And if I let it keep going, it will end up modifying the entire source tree with random "try this" crap. And each iteration, it confidently tells me: "Perfect! I have found the root cause! It is [garbage bullshit]. I have corrected it and the code is now completely working!"

These tools are cute, but they really need to go a long way before they are actually useful for anything more than trivial toy projects.