In a typical planning problem, where the world is fully observable and deterministic, the initial state is defined by specifying the value for each feature for the initial state.

There are several different kinds of goals:

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  An achievement goal is a proposition that must be true in the final state.

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  A maintenance goal is a proposition that must be true in every state through which the agent passes. These are often safety goals – the goal of staying away from bad states.

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  A transient goal is a proposition that must be achieved somewhere in the plan.

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  A resource goal is the goal of minimizing some resource in the plan. For example, the goal may be to minimize fuel consumption or the time required to execute the plan.

In the rest of this chapter, we concentrate on achievement goals, where the goal is a set of assignment of values to features, all of which must hold in the final state.