Those are scripts too. And they don't exist in K1. And... it's the same thing anyway.
The talked to scripts check a local boolean that is specifically reserved for whether the NPC has been talked to yet. Although that does remind me, at some point in the initial conversation, you'll have to fire a script that sets the boolean. k_act_talktrue in K1 and a_talktrue in K2. Forgot to mention that before.