Coming up With Good Excuses: What to do When no Plan Can be Found

Abstract

When using a planner-based agent architecture, many things can go wrong.First and foremost, an agent might fail to execute one of the planned actions for some reasons.Even more annoying, however, is a situation where the agent is incompetent, i.e., unable to come up with a plan.This might be due to the fact that there are principal reasons that prohibit a successful plan or simply because the task's description is incomplete or incorrect.In either case, an explanation for such a failure would be very helpful.We will address this problem and provide a formalization of coming up with excuses for not being able to find a plan.Based on that, we will present an algorithm that is able to find excuses and demonstrate that such excuses can be found in practical settings in reasonable time.