People say the best way to see this is asking AI about subject you’re expert of.

This is not always possible, I had people who said “but I’m not expert at anything”. Another way is to ask them about yourselves. For example if you have reddit account that is has some age, Gemini has deal with reddit and feeds them everything that’s posted. First response might even look good, but continue talking (as it is getting more ridiculous), don’t try correct, you can see how it is making shit up.

Since they are feeding it with everything lemmy might also work.