Ai addon builder

is an unimplemented entity found in the  files of Alien Swarm, Portal 2, and Counter-Strike: Global Offensive. This entity was part of the "Directed Design Experiments" performed at Valve in November 2007, and is the base of a modular AI system, wherein enemies could collect upgrade chips to gain new abilities and drop them when dead, allowing other enemies to collect and reuse them. This code has never been released to the public or used in its entirety in a Valve title. A related keyvalue called  was defined in, and a related input called   was defined in.