Not as noisy as some of claptrap's action skills, all of his skills make the other people in your party get them too so he can be hella annoying at the wrong times. So its lore accurate to claptrap, he has one that makes you bounce around on a rubber ducky and one that forces you to empty your mag with every shot and one that doesn't let you stop shooting, its so fun.
oh right, his abilities are very autistic but I always thought they were funny. I assumed he was a DLC character like Jack until I looked it up just now, since he's pretty out there and there and there are probably a lot of people who would pay to play as claptrap, but nope. Apparently the 2nd dlc character was just some random chick I forgot was in the game.