AAMAS Conference 2026 Conference Paper
UAM-MARL: Uncertainty-Aware Modality-Enhanced Multi-Agent Reinforcement Learning with LLM-Guided Graph Policies
- Zichen Song
- Weijia Li
Multi-agent systems (MAS) are increasingly deployed to solve complex embodied tasks, yet coordination efficiency, reward design, and robustness remain persistent challenges. While multi-agent reinforcement learning (MARL) provides a principled framework for cooperation, existing LLM-driven approaches often assume perfect perception and static planning, which is unrealistic in noisy and dynamic environments. In practice, discrepancies between language-based reasoning and uncertain multimodal perception, the semantic–perception gap, lead to incorrect subgoal assignments, misaligned rewards, and unstable coordination. To address this limitation, we propose UAM-MARL, an uncertainty-aware modalityenhanced MARL framework. UAM-MARL integrates three components: (1) an uncertainty-aware perception module that estimates confidence scores over multimodal inputs and propagates them to the planner, (2) a cross-modal consistency checker that validates the alignment between LLM-generated plans and environment observations, and (3) an uncertainty-weighted reward generator that composesindividualandteamrewardsbyscalingreasoning-derived signals with perception confidence. These modules augment the LLM-based planner–critic and homology-guided graph policy, enabling more reliable coordination under noisy observations and dynamic disturbances. Experiments in the AI2-THOR simulator demonstrate that UAM-MARL achieves superior performance compared to centralized-LLM, dialogue-based LLM, and state-of-the-art MARL baselines, yielding higher success rates, shorter completion times, lower token costs, and stronger robustness to perception noise. Ablation studies further confirm the contribution of uncertainty modeling and cross-modal consistency to improving both efficiency and scalability.