TBH, I can’t even remember. I did it as a lark (more or less).
I just googled something like “best AI detectors” and found some articles listing what purport to be some of the better ones. I ran the paragraph of text against about 5 of them, with one definitely saying it was AI and the others saying it wasn’t.
Not very scientific, I concede. But I would be pretty sure that there is a lot of variance between/among these detectors.