OP-Bench: Benchmarking Over-Personalization for Memory-Augmented Personalized Conversational Agents

Yulin Hu, Zimo Long, Jiahe Guo, Xingyu Sui, Xing Fu, Weixiang Zhao, Yanyan Zhao, Bing Qin


Abstract
Memory-augmented conversational agents enable personalized interactions using long-term user memory and have gained substantial traction. However, existing benchmarks primarily focus on whether agents can recall and apply user information, while overlooking whether such personalization is used appropriately. In fact, agents may overuse personal information, producing responses that feel forced, intrusive, or socially inappropriate to users. We refer to this issue as **over-personalization**. In this work, we formalize over-personalization into three types: Irrelevance, Repetition, and Sycophancy, and introduce **OP-Bench**, a benchmark of 1,700 verified instances constructed from long-horizon dialogue histories. Using OP-Bench, we evaluate multiple large language models and memory-augmentation methods, and find that over-personalization is widespread when memory is introduced. Further analysis reveals that agents tend to retrieve and over-attend to user memories even when unnecessary. We further evaluate existing post-processing strategies for mitigating this issue, but find that they provide only limited improvements and often reduce personalization performance. Our results highlight over-personalization as a challenging and largely unresolved problem in memory-augmented dialogue systems.
Anthology ID:
2026.emnlp-main.1168
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:
26770–26827
Language:
URL:
https://aclanthology.org/2026.emnlp-main.1168/
DOI:
Bibkey:
Cite (ACL):
Yulin Hu, Zimo Long, Jiahe Guo, Xingyu Sui, Xing Fu, Weixiang Zhao, Yanyan Zhao, and Bing Qin. 2026. OP-Bench: Benchmarking Over-Personalization for Memory-Augmented Personalized Conversational Agents. In Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing, pages 26770–26827, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
OP-Bench: Benchmarking Over-Personalization for Memory-Augmented Personalized Conversational Agents (Hu et al., EMNLP 2026)
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PDF:
https://aclanthology.org/2026.emnlp-main.1168.pdf