All boss encounters in FFXIV use what we internally refer to as a monitoring program and gambit algorithms to dictate their behavior.

The monitoring program takes the following factors into account for every encounter:

The number of participating players
The HP and enmity level of all participating players
The HP of the boss enemy
The boss enemy's target
Time elapsed since the beginning of the encounter


By monitoring these factors, bosses are able to transition from one phase to the next, and activate certain abilities such as Titan's Upheaval or the fully charged ADS in Turn 2 of the Binding Coil.

Sounds like AI to me.