AI tooling must be disclosed for contributions

I’m not a big AI fan but I do see it as just another tool in your toolbox. I wouldn’t really care how someone got to the end result that is a PR.

But I also think that if a maintainer asks you to jump before submitting a PR, you politely ask, “how high?”

As a project maintainer, you shouldn't make rules unenforceable rules that you and everyone else know people will flout. Doing so comes makes you seem impotent and diminishes the respect people have for rules in general.

You might argue that by making rules, even futile ones, you at least establish expectations and take a moral stance. Well, you can make a statement without dressing it up as a rule. But you don't get to be sanctimonious that way I guess.

Except you can enforce this rule some of the time. People discover that AI was used or suspect it all the time, and people admit to it after some pressure all the time.

Not every time, but sometimes. The threat of being caught isn't meaningless. You can decide not to play in someone else's walled garden if you want but the least you can do is respect their rules, bare minimum of human decency.

It. doesn't. matter.

The only legitimate reason to make a rule is to produce some outcome. If your rule does not result in that outcome, of what use is the rule?

Will this rule result in people disclosing "AI" (whatever that means) contributions? Will it mitigate some kind of risk to the project? Will it lighten maintainer load?

No. It can't. People are going to use the tools anyway. You can't tell. You can't stop them. The only outcome you'll get out of a rule like this is making people incrementally less honest.