The tires that come on the bike are Specialized Ground Control 2BR 29x2.1" (front) and Fast Trak 2BR 29x2.0" (rear). The Stan's wheels are set up for tubeless as well. They'll come with tubes, but all you need to do is add sealant and air them up.
The max tire clearance for the Ripley according to Ibis is 2.25 for most brand tires.. You'll probably be able to fit some of the 2.3s out there, but not all and you won't be able to go any bigger than that.
If you've got any other questions or need anything else from us please let us know.