AI stands for Artificial Intelligence, and refers to the giant artificial brains that built Torei.
Torei would not exist were it not for the AIs launched hundreds of millennia ago by the Laminate Culture. The geode craft launched by the Lamination People contained enough machinery to build the factory that produced the three main AIs: the polar Dæmons of Mazos, Dahom, and the Dockmaster who remains up in space.
These AIs have one goal that they work toward: the terraforming of Torei. Their incredible age and the timescale of the terraforming project mean that they make choices from a perspective that is fundamentally alien to us.