MAS-on-the-Fly: In-Context Structural Adaptation of LLM-Based Multi-Agent Systems

Guangyi Liu; Haojun Lin; Huan Zeng; Heng Wang; Quanming Yao

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arXiv · 2602.13671

MAS-on-the-Fly: In-Context Structural Adaptation of LLM-Based Multi-Agent Systems

Guangyi Liu·Haojun Lin·Huan Zeng·Heng Wang·Quanming Yao

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Abstract

Large Language Model (LLM)-based multi-agent systems (MAS) have emerged as a promising paradigm for complex tasks. However, existing works often rely on manual designs or "one-size-fits-all" automation and lack adaptability after deployment. We study in-context structural adaptation, where structured experience conditions both query-dependent system generation and execution-time reconfiguration without updating LLM parameters. We introduce MASFly, which realizes this adaptation through two complementary mechanisms. First, a retrieval-augmented SOP instantiation mechanism retrieves and adapts successful collaboration patterns to construct a query-specific MAS. Second, an experience-enhanced process supervision mechanism uses a dedicated Watcher agent to monitor execution against prior failure experience and reconfigure the system upon abnormal behavior. Experiments demonstrate that MASFly achieves state-ofthe-art performance, including a 61.7% success rate on TravelPlanner, with strong task adaptability and robustness.

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Guangyi Liu, Haojun Lin, Huan Zeng, Heng Wang, Quanming Yao. 2026-08-31. MAS-on-the-Fly: In-Context Structural Adaptation of LLM-Based Multi-Agent Systems. https://arxiv.org/abs/2602.13671

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