Title: SkillEvo: An Experience Learning Framework with  Reinforcement Learning for Skill Evolution
Primary area: applications to computer vision, audio, language, and other modalities
Keywords: Web Agents，GRPO ， Experiential Learning

Abstract: Large Language Models (LLMs) have evolved into agents capable of perception, reasoning, and acting in open environments. Yet, in long-horizon tasks with sparse rewards, existing methods are often inefficient. Group-based reinforcement learning (e.g., GRPO) provides critic-free and stable optimization, but its coarse credit signals cannot distinguish high-quality trajectories from those that merely succeed but contain redundant or invalid actions, leading to weak generalization. We propose SkillEvo(Skill Evolution), a two-stage framework for efficient and sustainable agent learning. In the first stage, WebGRPO integrates a Reasoning and Execution Reward Model (RXERM) to deliver fine-grained feedback, and employs a dual-uncertainty filtering strategy to select informative tasks, improving sample efficiency and stability. In the second stage, SkillGenesis transforms trajectories into reusable skills, organized in a dynamically evolving Skill Path Graph (SPG). This enables skill composition, reuse, and the emergence of composite skills for long-term adaptability. On WebArena-Lite, SkillEvo raises the success rate of Llama-3.1-8B from 4.8% to 60.4% and GLM-4-9B from 6.1% to 57.6%, achieving new state-of-the-art results. These findings highlight that effective long-horizon learning requires not only refined credit signals but also systematic mechanisms for skill evolution.

TL;DR: SkillEvo: An Experience Learning Framework with Reinforcement Learning for Skill Evolution