Does Chuy write his own material on Chelsea Lately?

I love love love Chelsea Lately and it just wouldn’t be the same without Chuy. I started following them on twitter a few months ago and their tweets are just as hilarious as the show. I’m just wondering if Chuy is as funny as he is portrayed in the show and if he actually writes his own tweets. I know that the writers do write some of his “jokes,” but I want to know if he writes anything at all. is he really that funny? or is he basically just a mascot to Chelsea?