> With GPT, even when I told it to not do it, it still did that, but that was some time ago and it was not done via the API, so I dunno.

Personally I think it's a lot better via the API than ChatGPT. ChatGPT doesn't let you edit the "system prompt" which is really where you wanna put "how to" instructions, so it really follows them. Instructions put in the user message aren't followed as closely as when you use the system prompt, so probably why it still did something, if you were using ChatGPT.