[TheObviousOne]

Interesting tactics might going the other direction.

Asking to generate in a super human capabilities...

write a 65 pages of poem about X...

[choeger]

Or just questions about three or four wildly different fields of science, sports and culture you happen to have more than a layman's understanding. If the answers are somewhat plausible, it's probably a model. Or your life partner.

[8bitsrule]

Or ask two or three historical questions that very few humans would know anything about ... but a well-trained model would.