arXiv Machine Learning

Where to Start, How to Move: Analyzing Curricula under GRPO for Long-Horizon LLM Agents

arXiv AI
Oct 31

SCOPE: Selective Critical-Step On-Policy Self-Distillation for Agentic Reinforcement Learning

SCOPE is a new framework for selective critical‑step on‑policy self‑distillation in agentic reinforcement learning. After a supervised warm‑up, the policy examines its own trajectories, generates hindsight skills for each step, and distills guidance only at selected error steps, using a bounded teacher‑student coefficient and a success‑relative pairwise length reward. Experiments on ALFWorld and WebShop show consistent performance gains across multiple model backbones, with Qwen2.5‑3B achieving 97.7 % success on ALFWorld and 85.2 % on WebShop, and Qwen3‑32B reaching 99.2 % on seen tasks and 94.0 % on unseen tasks.

By Qirui Liu, Wei Cao, Yu Mi, Yichen Sun, Xuekun Zhang, Lei Liu, Yue Shen, Zhixuan Chu
arXiv AI
Sep 30

Learning from Viable Failure Prefixes: Milestone Viability Potential Policy Optimization for Long-Horizon LLM Agents

The paper introduces Milestone Viability Potential Policy Optimization (MVPO), a reinforcement learning algorithm designed for long‑horizon large language model agents. MVPO addresses the zero‑credit failure problem by learning from viable failure prefixes, estimating prefix potential over Union‑Find viability regions, and repairing zero‑credit groups with potential‑difference advantages. Experiments on Qwen2.5‑1.5B‑Instruct demonstrate that MVPO outperforms eight strong baselines, improving success rates on ALFWorld and WebShop with minimal overhead.

By Qi Zhou, Yuanfan Li
arXiv AI
Sep 3

PGPO: Potential-Guided Policy Optimization for Multi-Turn Agentic Tasks

The paper introduces Potential-Guided Policy Optimization (PGPO), a method for multi-turn agentic tasks that improves credit assignment by estimating empirical state potentials from anchor-state-group return statistics. PGPO derives action advantages from potential differences between adjacent states, enabling cross-trajectory credit propagation and finer-grained step-level credit assignment, especially within failed trajectories. Experiments on ALFWorld and WebShop demonstrate strong performance compared to recent group-based reinforcement learning methods, with negligible training overhead.

By Yuyao Zheng, Haipeng Sun, Junwei Bao, Lemao Liu, Hongfei Jiang, Yang Song, Dejing Dou
arXiv Machine Learning
Sep 1

PAC: Progress-Augmented Advantage Curriculum for Multi-Task Reinforcement Learning of LLMs

arXiv:2608.30528v1 Announce Type: new Abstract: Reinforcement learning (RL) is used to improve the reasoning abilities of LLMs, while training data span heterogeneous tasks. However, most RL post-tra...

By Yuanqiang Yu, Yanzhao Zheng, Zhentao Zhang, Tianze Xu, Chao Ma, Jihuai Zhu, Jiashun Liu, Xinle Deng, Baohua Dong, Hangcheng Zhu, Ruohui Huang
arXiv AI
Aug 19

PlanPO: Group Planning-Aware Policy Optimization for Multi-Turn Agentic LLMs

PlanPO introduces a group planning-aware policy optimization method for multi-turn agentic large language models, addressing the issue of advantage collapse caused by treating all successful trajectories equally. By incorporating coarse-to-fine advantage signals that reflect differences in trajectory and turn lengths, PlanPO encourages agents to learn generalizable planning and generation behaviors. Experiments show a 27.2% average improvement over GRPO on benchmarks such as ALFWorld, WebShop, and SciWorld, with minimal extra training cost.

By Dayang Liang, Liyuan He, Xuan Feng, Shuxin Li, Bo An, Yunlong Liu
arXiv AI
Oct 31

Where to Learn and How Far to Roll Out: Efficient Adaptive Training for GUI Agents

The paper proposes a two-stage adaptive training framework for GUI agents that addresses both where to learn and how far to roll out during training. It creates reusable intermediate checkpoints from expert trajectories and selects informative pivots using action disagreement to focus one-step reinforcement learning on uncertain decisions. The method then progressively expands policy responsibility through adaptive Local, Suffix, and Root training, enabling repeated training from intermediate states and reducing environment interaction by 56‑61% while improving task performance on MobileGym and CUA‑Gym‑Hub.

By Yuxiang Chai, Quyu Kong, Panrong Tong, Steven Hoi, Yue Wang