[edit]
Planning with Formal Reachability Guarantees in Goal-Oriented MDPs with Dead-Ends
Proceedings of the 42nd Conference on Uncertainty in Artificial Intelligence, PMLR 337:5731-5739, 2026.
Abstract
Goal-oriented {Markov} Decision Processes with unavoidable dead-ends pose a significant challenge to standard planning algorithms, as the goal cannot always be reached with probability $1$. In certain applications, it can be desirable to optimize efficiency only over successful trajectories while enforcing a lower bound on goal reachability, yet no existing method directly addresses this conditional formulation, whose non-linear structure makes direct optimization difficult. To overcome this, we introduce a tractable approximation. Working within an unconstrained utility-maximization framework, we derive an analytical formula that determines a value for the goal-reward parameter sufficient to guarantee that the optimal policy respects the requested reachability threshold. The proposed approach is evaluated on two common benchmark domains, Aircraft Routing and Exploding Blocksworld, and compared against state-of-the-art constrained optimization methods, specifically i-dual and Chance-Constrained. Results show that our method offers a compelling trade-off: it significantly reduces the expected cost compared to conservative lexicographic approaches (i.e. i-dual), while avoiding the failure-seeking bias inherent to methods modelling artificial zero-cost give-up action (i.e. Chance-Constrained).