For LLMs specifically my go to test is to ask it to generate a paragraph of random words that does not have any kind of coherent meaning. It specifically asks them to do the opposite of what they’re trained to do so it trips them up pretty reliably. Closest I’ve seen them get was a list of comma separated random words and that was after giving them coaching prompts with examples.
Yeah, exactly. Those aren’t words, they aren’t random, and they’re in a comma separated list. Try asking it to produce something like this:
Green five the scoured very fasting to lightness air bog.
Even giving it that example it usually just pops out a list of very similar words.