I tried both ChatGPT 4 and Perplexity.
The second one I recently asked for lists of names - of various things. It was duplicating names, so I pointed that out to it, wrote to it that I wanted unique names.
"Now I understand, you want unique names, not repeated ones. Here's the list:"
And again duplicate names, quite a few.
Me to ChatGPT:
"Those methods, AAA, BBB, CCC, do not exist in B4J's DDD class"
ChatGPT: "You are right, AAA, BBB, CCC methods do not exist in B4J's DDD class, sorry for my mistake. Here is the modified source:"
Guess what? Full of AAA, BBB, CCC methods again (and again, and again, and...)