Cooperation Breakdown in LLM Agents Under Communication Delays
Keita Nishimoto, Kimitaka Asatani, Ichiro Sakata
TL;DR
The paper tackles cooperation formation in LLM-based multi-agent systems under communication delays and resource disparities. It introduces the FLCOA five-layer framework and analyzes the impact of the fifth, Infrastructure Layer, using a Continuous Prisoner’s Dilemma implemented over a server–client architecture with delays $D_i$ and updates at intervals $\Delta t$, where agents receive the past $t_m$ history and current states as input. Empirical results reveal a non-monotonic, U-shaped relationship between delay and mutual cooperation: moderate delays increase exploitation and reduce cooperation, while very large delays diminish exploitation chains and partially recover cooperation; a simple tit-for-tat–based model reproduces these patterns. The findings underscore that infrastructure-level controls and resource allocation critically influence cooperative outcomes in LLM-MAS, suggesting new directions for research and deployment strategies. The work provides a concrete methodology to study latency effects and highlights the need for latency-aware design in real-world AI-agent collaborations.
Abstract
LLM-based multi-agent systems (LLM-MAS), in which autonomous AI agents cooperate to solve tasks, are gaining increasing attention. For such systems to be deployed in society, agents must be able to establish cooperation and coordination under real-world computational and communication constraints. We propose the FLCOA framework (Five Layers for Cooperation/Coordination among Autonomous Agents) to conceptualize how cooperation and coordination emerge in groups of autonomous agents, and highlight that the influence of lower-layer factors - especially computational and communication resources - has been largely overlooked. To examine the effect of communication delay, we introduce a Continuous Prisoner's Dilemma with Communication Delay and conduct simulations with LLM-based agents. As delay increases, agents begin to exploit slower responses even without explicit instructions. Interestingly, excessive delay reduces cycles of exploitation, yielding a U-shaped relationship between delay magnitude and mutual cooperation. These results suggest that fostering cooperation requires attention not only to high-level institutional design but also to lower-layer factors such as communication delay and resource allocation, pointing to new directions for MAS research.
