The planet was mostly covered by water, with the few small landmasses not containing any life. The water was suited for Xindi-Aquatics to move in without protection. Degra described it as bleak and desolate, barely habitable. All of the Xindi facilities on Azati Prime were located underwater, including the construction yards for the Xindi weapon. (ENT: "Stratagem", "Azati Prime")
In February of 2154, Enterprise reached the system after a long search for the Xindi weapon. Azati Prime was one of two inner planets detected to have substantial Xindi activity at this time, and the weapon launch was imminent.
Any information Degra gave about the planet might be considered suspect, given that he gave the information to Archer, which he later claimed to have distrusted to some extent from the beginning. Degra also implied it would naturally be one of the first planets the Insectoids might attack should they turn on the other species.
According to Startrek.com, this was a class M planet with a colony population of 1,000 Xindi-Primates and Xindi-Arboreals.