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arXiv · 2511.06449

FLEX: Continuous Agent Evolution via Forward Learning from Experience

Zhicheng Cai·Xinyuan Guo·Yu Pei·Jiangtao Feng·Jinsong Su·Jiangjie Chen·Ya-Qin Zhang·Wei-Ying Ma·Mingxuan Wang·Hao Zhou
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Abstract

Autonomous agents driven by Large Language Models (LLMs) have revolutionized reasoning and problem-solving but remain static after training, unable to grow with experience as intelligent beings do during deployment. We introduce Forward Learning with EXperience (FLEX), a gradient-free learning paradigm that enables LLM agents to continuously evolve through accumulated experience. Specifically, FLEX cultivates scalable and inheritable evolution by constructing a structured experience library through continual reflection on successes and failures during interaction with the environment. FLEX delivers substantial improvements on mathematical reasoning, chemical retrosynthesis, and protein fitness prediction (up to 23% on AIME25, 10% on USPTO50k, and 14% on ProteinGym). We further identify a clear scaling law of experiential growth and the phenomenon of experience inheritance across agents, marking a step toward scalable and inheritable continuous agent evolution. Project Page: https://flex-gensi-thuair.github.io.

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Zhicheng Cai, Xinyuan Guo, Yu Pei, Jiangtao Feng, Jinsong Su, Jiangjie Chen, Ya-Qin Zhang, Wei-Ying Ma, Mingxuan Wang, Hao Zhou. 2025-12-08. FLEX: Continuous Agent Evolution via Forward Learning from Experience. https://arxiv.org/abs/2511.06449

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