Opus, yes, the $20/mo version. I usually don’t generate copy. My use cases are code (both “serious” and “the nice to have code I wouldn’t bother writing otherwise”), learning how to do stuff in unfamiliar domains, and just learning unfamiliar things in general. It works well as a very patient teacher, especially if you already have some degree of familiarity with the problem domain. I do have to check it against primary sources, which is how I know the percentage of hallucinations is very low. For code, however I don’t even have to do that, since as a professional software engineer I am the “primary source”.