Benchmark Almanac

PerMemBench

Not in model cards

Memory systems for long-running agents decide what to store from years of interactions across many domains and user personas. Later questions check whether the system kept the context that matters for each user. The benchmark tests whether memory policies can adapt to the person instead of storing everything the same way.

The paper also proposes its own session-level storage gate. 45 Hugging Face upvotes and about 13 GitHub stars. The scoring rule should be checked before importing scores.

Made by
KAIST
Released
May 2026
Kind
Learning from the context
Level
Everyday
Answers
Short answer
Tasks
All public

In the authors’ words

Existing large language model (LLM) based memory systems apply universal, static policies that overlook a fundamental reality: the contexts that are worth storing in memory are different across users. This misalignment wastes limited memory budget on transient interactions while failing to preserve critical context for long horizon tasks. To address this gap, we investigate an underexplored question: can LLM based memory systems learn personalized memory policies? We introduce PerMemBench, the first benchmark for evaluating personalized memory systems, featuring multi year, multi domain interaction histories across diverse user personas. We further present the first empirical study of memory personalization, proposing session level storage gating, a lightweight framework that selectively bypasses memory operations for transient sessions. Our study confirms that personalization yields substantial retention gains under perfect gating, yet reveals that accurate gating remains an open and critical challenge.

Abstract of Personalize-then-Store: Benchmarking and Learning Personalized Memory for Long-horizon Agents (arXiv:2605.25535, CC0)

No scores here yet

No lab, leaderboard or Epoch AI run has reported a score for PerMemBench yet.

No lab model card reports it yet

We read the headline results of 522 launch posts from 52 labs, and none of them list this benchmark.

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