Adaptive Conservation-Consistent Multi-Agent Policy Optimization for Tail-Risk-Aware Inventory Networks

Authors

  • Andre Kim Manning College of Information and Computer Sciences, University of Massachusetts Amherst, USA
  • Lana Foster Manning College of Information and Computer Sciences, University of Massachusetts Amherst, USA
  • Hannah Lopez Manning College of Information and Computer Sciences, University of Massachusetts Amherst, USA
  • Jade Ross Manning College of Information and Computer Sciences, University of Massachusetts Amherst, USA

DOI:

https://doi.org/10.54097/vbke0c45

Keywords:

Multi-agent policy optimization, Supply chain inventory, Conservation constraints, CVaR, Adaptive risk control, Differentiable simulation

Abstract

Capacity-limited inventory networks must reconcile locally requested shipments with executable warehouse flows while controlling losses under supply and demand disruptions. We introduce a decentralized, parameter-shared policy trained through a differentiable, mass-balanced simulator. A nodewise command-to-realization residual, derived from discrete inventory conservation, penalizes infeasible requested flows. An online-adjusted risk weight couples mean episode cost with the upper-tail conditional value-at-risk (CVaR). Ten independent seeds compare seven policies across four synthetic disturbance regimes (400 held-out trajectories per method, seed and regime). Under combined stress, mean cost is 4906.8 versus 4979.7 for risk-neutral policy optimization, while CVaR90 is 8464.8 versus 8580.9. Against a fixed-risk comparator with a closely matched final risk weight, the adaptive formulation further reduces stress CVaR90 by 39.4 cost units. Requested-but-unshipped flow drops from 15.80 to 2.27 units/day. Realized transitions conserve inventory under every policy: the residual regulates planning consistency, not physical conservation itself. Results reflect a reproducible synthetic benchmark rather than field validation.

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Published

05-11-2026

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