arXiv AI

The Retriever Should Remember: Experience-Amortized Reranking for Long-Term Agent Memory

arXiv AI
Sep 11

What Should an Agent Forget? Separating What Is Stored from What Is Used

The paper introduces RD-Forget, a training‑free framework that separates what a persistent language agent stores from what it uses at answer time. It keeps a source archive of all observations while a query‑conditioned memory view filters evidence relevant to the current question, using a frozen language‑model curator to group facts into semantic slots and preserve multi‑hop relations. The approach employs rate‑distortion principles to stay within a memory budget and demonstrates improvements across conversational memory, knowledge updating, fact consolidation, long‑context reasoning, and personalization tasks.

By Yuhang Li, Yuchen Li
arXiv AI
Oct 2

What Should an Agent Remember? Disentangling Retention from Retrieval in Bounded-Memory Evaluation

The paper introduces a streaming-recall benchmark that separates retention and selection decisions for persistent agents. It shows that query‑aware selection boosts recall by 15.5 points when access is fixed, while mixed comparisons inflate gains due to changes in history access. The study finds that under bounded retention, failures stem from eviction rather than ranking errors, and that dense retrieval can outperform lexical retrieval on natural text.

By Juli Huang
arXiv Machine Learning
Jun 15

Efficient Rationale-based Retrieval: On-policy Distillation from Generative Rerankers based on JEPA

arXiv:2604. 23336v3 Announce Type: replace-cross Abstract: Unlike traditional fact-based retrieval, rationale-based retrieval typically necessitates cross-encoding of query-document pairs using large language models, incurring substantial computational costs.

By Teng Chen, Sheng Xu, Feixiang Guo, Xiaoyu Wang, Qingqing Gu, Hongyan Li, Luo Ji
arXiv AI
Sep 4

When Users Don't Ask: Benchmarking Context-Driven Memory Retrieval in Conversational Agents

The paper introduces LOCOMO-CONV, a conversational memory benchmark that expands on the existing LoCoMo dataset with four query styles—dialog, implicit, counterfactual, and composed—designed to evaluate memory systems in realistic conversational settings. Experiments across five memory systems reveal that conversational framing uncovers significant retrieval gaps missed by traditional QA benchmarks, particularly for implicit and composed queries, and that strong retrieval does not necessarily translate into higher response quality. The study also highlights silent grounding in implicit queries, where memory enhances contextual grounding without explicitly presenting the gold fact, suggesting a need for reasoning-based memory elaboration.

By Wen-Yu Chang, Yun-Nung Chen
arXiv Machine Learning
Sep 24

The Recall Ceiling of LLM Recommendation Reranking

The paper examines LLM-based recommendation rerankers that are often evaluated under an oracle protocol, which guarantees the ground-truth item is present in the scored set. Across Amazon datasets, this protocol overestimates realistic NDCG@10 by 92–95% because realistic retrieval only covers 2–19% of relevant items at K=100, creating a recall ceiling that limits any closed-candidate reranker's top‑k NDCG. The authors find that various optimisation strategies—including prompt engineering, model scaling, sequential models, supervised neural rerankers, LoRA fine‑tuning, hybrid retrieval, score‑aware prompting, and LLM+CF fusion—do not significantly improve over a collaborative‑filtering baseline under realistic retrieval, and they propose a Recall‑Aware Evaluation Protocol (RAEP) to better assess rerankers in low‑recall regimes.

By Zhaohui Wang