Any text (book, essay, blog, comment) which includes any lines of unedited LLM output should come with a statement saying so. Even if the whole thing was very carefully edited and reviewed and the author is certain there's no obvious trace of LLM usage, they should still always say so.

Not because the LLM "deserves credit" (a disgusting trend, I find) but because:

A. The millions of humans who got ripped off in the process of their knowledge and time being hoovered up, digitised and productised deserve credit

B. Your artistic, aesthetic and ethical choices need to be assumed fully.

I can't see law working here, so I think it'll have to be cultural. Cultural means these discussions on here, for one. I implore every LLM user reading this to consider full honesty when using these tools.

I can picture the smart replies now so allow me to cut off one obvious one - no, business emails don't count, all business comms were already sloppified years ago. I mean anything that could reasonably be construed as creative, anything purporting to be sincere personal writing.