No. There aren't any APIs for tournaments. The framework only allows you to create and monitor games. The tournament logic must exist in your code. That being said, most types of tournaments (Round-Robin, Single/Double Elim etc) are simple to implement.
@AuraGuardian Thank you for the advice, normally I would listen. But bootmatt and I actually seem to get along well. I've played quite a few coin games with him, and I have not had to boot him once. I am just hoping he will not spam me, and we can continue our cordial relationship.
I made first production version of this that works relatively well. I also did realize that fizzer optimized the site terribly. Waiting 5 seconds for a bunch of items to display. Really? It takes 40 seconds to create a tournament that's relatively simple. Would be better had the site been optimized. I don't think I will spam this much. I may run it on lambda to invite a subset of warzone players every hour (not the whole pool) so that hopefully tournament section will get better here.