Learning What to Share and What to Personalize: Hierarchical Strategy Co-Evolution for Agent Memory

Yupeng Han, Shuochen Liu, Kai Zhang, Ze Liu, Zhihong Pan, Xianquan Wang


Abstract
Memory-augmented agents maintain compact user profiles throughout extended conversations, enabling personalized and consistent responses without the need to process the entire dialogue history. The quality of these user profiles relies on the underlying memory management strategy: at each step, the agent must determine what to retain, compress, or discard. However, existing methods typically employ a static, one-size-fits-all strategy established before training. In practice, the optimal memory decision is inherently user-specific and dynamically evolves alongside policy optimization. To address this, we propose HiPS (Hierarchical Personalized Strategy), a framework that decouples memory management into a globally shared foundation and a user-specific adaptive tier. Specifically, HiPS employs Universal Strategy to extract shared principles from cross-persona trajectories, alongside Persona Delta Distillation to generate tailored rules for users whose behaviors diverge from general patterns. Cross-Level Rule Flow dynamically calibrates their boundary by promoting broadly validated personal rules and demoting contradicted global ones. The architecture establishes a co-evolution loop where a mechanism guarantees that all strategy refinements are anchored to task outcomes. Extensive experiments demonstrate consistent improvements over memory-augmented baselines.
Anthology ID:
2026.emnlp-main.1544
Volume:
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Month:
October
Year:
2026
Address:
Budapest, Hungary
Editors:
Hung-Yi Lee, Sunipa Dev, Jessy Li, Desmond Elliott
Venue:
EMNLP
SIG:
SIGDAT
Publisher:
Association for Computational Linguistics
Note:
Pages:
35232–35249
Language:
URL:
https://aclanthology.org/2026.emnlp-main.1544/
DOI:
Bibkey:
Cite (ACL):
Yupeng Han, Shuochen Liu, Kai Zhang, Ze Liu, Zhihong Pan, and Xianquan Wang. 2026. Learning What to Share and What to Personalize: Hierarchical Strategy Co-Evolution for Agent Memory. In Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing, pages 35232–35249, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
Learning What to Share and What to Personalize: Hierarchical Strategy Co-Evolution for Agent Memory (Han et al., EMNLP 2026)
Copy Citation:
PDF:
https://aclanthology.org/2026.emnlp-main.1544.pdf