titleAgent-G^2: Gaussian Guidance for Agentic Reinforcement Learning
authorsZixuan Wang, Yanrui Miao, Zhengxi Lu, Teng Pan, Yiwen Qiu, Hongxing Li, Peng Qiu, Ruiqing Zhang, Yongliang Shen
date2026-08-24
venuearXiv (preprint, not peer reviewed)
idarXiv:2608.23318
affiliationZhejiang University
upvotes23 (Hugging Face Daily Papers, 2026-11-01)
linksabs pdf hf code
abstractHint-based reinforcement learning addresses reward sparsity in long-horizon agentic tasks by retaining a prefix of an expert trajectory before each rollout, letting the policy explore from a state closer to success. Its effectiveness hinges on the guidance depth: how much of the trajectory to keep. Existing methods treat this depth as a deterministic scalar. Scheduled approaches share one value across samples and ignore per-task heterogeneity; per-sample probing estimates it separately at the cost of extra rollouts. We find that useful guidance occupies a band of depths whose informativeness profile is approximately Gaussian around the band center, rather than concentrating at a single optimal point. We propose Agent-G^2, a Gaussian guidance framework that draws the depth per task from a Gaussian whose center and spread are estimated online from rollouts already collected for policy optimization, requiring no probe rollouts or learned depth predictor. The center combines a global baseline with per-cluster difficulty, and the spread tracks within-cluster variance. We evaluate Agent-G^2 on ALFWorld and WebShop on Qwen2.5-1.5B / 7B-Instruct. Agent-G^2 outperforms the strongest hint-based, hint-free, and Aux-RL baselines on ALFWorld by 2.3 / 3.9 / 7.4 points at under one-third the rollout cost of per-sample probing.

cite

@misc{wang2026agent,
  title={Agent-G^2: Gaussian Guidance for Agentic Reinforcement Learning},
  author={Zixuan Wang and Yanrui Miao and Zhengxi Lu and Teng Pan and Yiwen Qiu and Hongxing Li and Peng Qiu and Ruiqing Zhang and Yongliang Shen},
  year={2026},
  eprint={2608.23318},
  archivePrefix={arXiv},
  url={https://arxiv.org/abs/2608.23318}
}