Note that a different binding f results in a different multi-agent plan . Thus one recipe can be part of many different plans. Because world knowledge is incomplete, we allow some scripts to remain unbound. The problem of observational cooperation becomes one of taking a series of agent observations and possible multi-agent plans, and returning a binding f that binds yourself to a script in some maximally utile way. Utility rates the desirability of accepting a plan and binding from the observing agent's perspective.
Utility is a way to distinguish between multi-agent plans when several plans are likely.
The utility measurement u is domain-specific and depends on several predefined factors.