Give perception a memory
Separate a character’s immediate senses from what it remembers. An NPC that loses sight of a moving target can turn toward the last known location and search nearby. Log what triggered the change so a designer can tell whether the decision came from perception, navigation, or a scripted event.
Make transitions legible
Give an alert transition enough time to read and a visible or audible cue that fits the world. Review a quiet route and a crowded encounter, then compare when the character sees a threat, commits to an action, and returns to a patrol.