Ruoran Li
2026
MemPO: Self-Memory Policy Optimization for Long-Horizon Agents
Ruoran Li | Xinghua Zhang | Haiyang Yu | Shitong Duan | Xiang Li | Wenxin Xiang | Chonghua Liao | Xudong Guo | Yongbin Li | Jinli Suo
Findings of the Association for Computational Linguistics: ACL 2026
Ruoran Li | Xinghua Zhang | Haiyang Yu | Shitong Duan | Xiang Li | Wenxin Xiang | Chonghua Liao | Xudong Guo | Yongbin Li | Jinli Suo
Findings of the Association for Computational Linguistics: ACL 2026
Long-horizon agents face the challenge of growing context size during interaction with environment, which degrades the performance and stability. Existing methods typically introduce the external memory module and look up the relevant information from the stored memory, which prevents the model itself from proactively managing its memory content and aligning with the agent’s overarching task objectives. To address these limitations, we propose the self-memory policy optimization algorithm (MemPO), which enables the agent (policy model) to autonomously summarize and manage their memory during interaction with environment. By improving the credit assignment mechanism based on memory effectiveness, the policy model can selectively retain crucial information, significantly reducing token consumption while preserving task performance. Extensive experiments and analyses confirm that MemPO achieves absolute F1 score gains of 25.98 over the base model and 7.1 over the previous SOTA baseline, while reducing token usage by 67.58% and 73.12%.
MOA: Multi-Objective Alignment for Role-Playing Agents
Chonghua Liao | Ke Wang | Yuchuan Wu | Ruoran Li | Fei Huang | Yongbin Li
Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)
Chonghua Liao | Ke Wang | Yuchuan Wu | Ruoran Li | Fei Huang | Yongbin Li
Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)
Role-playing agents (RPAs) require balancing multiple objectives, such as instruction following, persona consistency, and stylistic fidelity, which are not always perfectly aligned across different dimensions. While prior work has primarily relied on supervised fine-tuning or reinforcement learning with scalarized rewards, these approaches do not explicitly address the coordination of multiple reward dimensions during optimization. We present **MOA** (**M**ulti-**O**bjective **A**lignment), a reinforcement-learning framework that enables multi-dimensional, fine-grained rubric optimization for general RPAs. MOA introduces a novel multi-objective optimization strategy that trains simultaneously on multiple fine-grained rubrics to boost optimization performance. Besides, to address the issues of model output diversity and quality, we have also employed thought-augmented rollout with off-policy guidance. Experiments on PersonaGym and RoleMRC show that MOA consistently improves multi-dimensional role-playing performance over supervised and standard RL baselines. Under identical evaluation protocols, an 8B model trained with MOA reaches performance competitive with strong closed-source models across multiple evaluation dimensions. These results suggest that MOA provides a practical framework for training more capable general-purpose role-playing agents.