On proactivity and maintenance goals

Goals are an important concept in intelligent agent systems, and can take a variety of forms. One such form is maintenance goals, which, unlike achievement goals, define states that must remain true, rather than a state that is to be achieved. Maintenance goals are generally restricted to acting as trigger conditions for goals or plans, and often take no part in any deliberation process. These goals are reactive and are only acted upon when the maintenance conditions are no longer true. In this paper, we study maintenance goals that are proactive, in that the agent system needs to not only react when the maintenance conditions fail, but also anticipate the failures of these conditions, and act in order to avoid them failing. This can be done by performing actions that prevent the condition from failing, or suspending goals that will cause the maintenance conditions to fail. We provide a representation for maintenance goals that captures both their reactive and proactive aspects, algorithms that identify in advance where maintenance conditions may not hold, and mechanisms for enabling preventative actions in such situations. We also provide some experimental results on an implementation of these ideas.