There's no better way to find out than to test them for yourself.
But as a bit of info, they can do a number of things.
Initially, they'll wander around and wave their arms, bang their tools around, use emotes, look at and follow people and other bots, spray their paint cans, etc...
But, you can get them to do other things.
Give them events to go to certain bricks, and then trigger other events there.
Change their appearances to a set of pre-determined one, or any custom ones you yourself can create with your own Avatar editor.
Put them into teams and let them fight you and/or each other when in a minigame.
Much more that's simple and given straight away, and others which many will work out with creativity with the bots and the event systems.
They're really rather simple when you get down to it and think the events over a little bit.
And they're a lot of fun, and have a very decent AI.
But you really do just need to give them a test.
I'm sure we'll be seeing loads of brilliant things with them in the coming weeks.
I'm driving home on my phone.
Must be a big phone.