KnowMe-Bench: Benchmarking Person Understanding for Lifelong Digital Companions
Paper · 2026 · Tingyu Wu, Zhisheng Chen, Ziyan Weng et al.
Summary
Digital companions meant to support a user for years must do more than recall facts. They need to explain and anticipate behaviour from a person's motivations and values. Current long-term memory benchmarks mostly use chat logs or synthetic histories and mainly test retrieval. KnowMe-Bench instead draws on long autobiographical narratives (~4.7M tokens), which interleave actions, context and inner thoughts. A multi-agent pipeline with verify-and-revise checks and human expert validation turns each narrative into a time- and place-anchored cognitive stream. Flashbacks are moved to their original point in the chronology ("mnestic realignment"). Questions are evidence-linked and range from factual recall to attributing mental states and reasoning about decision principles. On several LLM backbones, retrieval-style memory (Naive RAG, Mem0) mostly boosts fact-level scores. Chronology and insight tasks remain weak, with MemOS helping more consistently. The benchmark shows that person understanding needs memory with explicit temporal provenance, not just a searchable fact store.
Key points
- Each narrative is split into five textual fields: visual observations, auditory inputs, situational context, background knowledge, and inner monologue. The pipeline runs in four stages: segmentation, atomic unit (ANU) extraction, timeline generation, and narrative generation.
- Evaluation has seven tasks in three levels:
- T1 Extract and T2 Abstain make up Level I, which focuses on Fact & Entity.
- Level II, Narrative Logic: T3 Temporal, T4 Order, T5 Trigger.
- Level III, Insight: T6 Mind–Body, T7 Principle.
- Tested backbones were Qwen3-32B, GPT-5-mini, DeepSeek-R1 and Gemini-3 Pro, each with Base, Naive RAG, Mem0 and MemOS variants. A-Mem was tested on Qwen3-32B only.
- An "update paradox" appears: state-updating memory can treat recalled past events as overwrites of the present state. For example, Qwen3-32B + A-Mem scores 55.7 on T6 but drops to 16.0 on T3.
- In closed-book contamination checks, Level II accuracy falls from 89.1 to 33.2 after de-identification. Level III stays at 0, so memorized literary knowledge does not explain the results.
Institutions
Fields, topics and concepts
📚 Shelves 6The field of science this work belongs to (OpenAlex fields).Computer Science · 16,667 worksArtificial Intelligence · 16,194 worksArts and Humanities · 16,039 worksLanguage and Linguistics · 15,891 worksPsychology · 1,552 worksSocial Psychology · 306 works
Cite
Cite as Tingyu Wu, Zhisheng Chen, Ziyan Weng, Shuhe Wang, Shuo Zhang, Sen Hu, Silin Wu, Qizhen Lan, Huacan Wang and Ronghao Chen. 2026. KnowMe-Bench: Benchmarking Person Understanding for Lifelong Digital Companions. Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers).
@inproceedings{wu2026knowme,
title = {{KnowMe-Bench: Benchmarking Person Understanding for Lifelong Digital Companions}},
author = {Tingyu Wu, Zhisheng Chen, Ziyan Weng, Shuhe Wang, Shuo Zhang, Sen Hu, Silin Wu, Qizhen Lan, Huacan Wang and Ronghao Chen},
booktitle = {Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)},
year = {2026},
doi = {10.18653/v1/2026.acl-long.1394},
url = {https://doi.org/10.18653/v1/2026.acl-long.1394}
}References
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