It's actually pretty fun, and I liked the character's ridiculous jump animation, haha. I think the randomizer for the levels needs work, though. It's a bit like someone just when into MSPaint and used the airbrush to place tiles, haha. Treasure chest were often stuck in the walls and stuff. Maybe this is actually secrets? I just thought of that lol, but it doesn't clue you in to how to find them, so I'm not so sure.
Luckily the controls were fun enough to keep it interesting, and the art and music was nice. If you do a sequel though, please invest some time into the level randomizer. I'd suggest designing small level "chunks", like various small series of platforms/floor patterns, and then stringing them together randomly into larger patterns so it gives it a better flow (I was thinking about doing this for a future William and Sly game). A lot of what makes a platformer fun is the rhythmic aspect of it, you know? Maybe scrap the random levels and just make them by hand is another option? The pure randomness of the levels made them all feel a bit similar, which is an ironic outcome.
It was still pretty fun, none-the-less! :D I haven't played very far, but I might come back to it later.