version 5 by Aaron Reed
Section: Red Flag Rules
Sometimes it is useful to add a third component to the specification of the task: the notion of a inhibitor that prevents the task from being performed until a certain condition is met. For this purpose, Intelligent Hinting defines a rulebook called the "red flag rules"; adding a rule for a task and causing it to fail under certain conditions will prevent that task from being attempted.
As it happens, Adventure never needs to make use of this, but here's a hypothetical example from "Beyond Zork," where we take a ride on a scenic tram and need to jump out at a certain support tower to explore the jungle below:
Reaching-The-Jungle is a task with venue Jungle Skyway. Requirements for Reaching-The-Jungle: do the action of exiting. A red flag rule for Reaching-the-Jungle: if first support tower is not visible, rule fails.
If the rule fails, the extension will try to "wait" until a move where the red flag rule succeeds.