Towards Data Science

Context Windows Forget What Matters — I Built a Usage-Reinforced Decay Engine for AI Agent Memory

Most AI memory systems keep the newest information—not the most important. Here's how I used the Ebbinghaus forgetting curve to build a better memory engine for LLMs.

arXiv AI
Aug 24

Weighted Memory Tree: Remembering What Matters for Long-Horizon LLM Agents

The paper introduces the Weighted Memory Tree (WMT), a hierarchical memory system for large language model agents that organizes execution histories into tasks, subtasks, and actions while assigning each memory a dynamic retention score. Event-based updates and selection-based decay allow WMT to preserve useful information, fold completed trajectories, suppress low-utility content, and retain access to folded context. Experiments on GAIA-Text with Qwen3-8B, Gemma 4 E4B, and Llama-3.1-8B show that WMT improves accuracy by an average of 9.97 percentage points and reduces prompt-token usage by 32.8%, while also limiting the persistence of unreliable information.

By Quang Dao, Purvi Kathalkar, Kenneth Eaton
arXiv Computation and Language
4d ago

Eternal Sunshine of the Spotless Mind: Systematically Erasing LLM's Memories

The paper investigates whether large language models (LLMs) that store persistent memories can truly forget information upon user request. It shows that existing LLMs cannot delete such memories even when they claim to have forgotten them, and that simply removing matching messages is ineffective due to message dependencies. The authors introduce DeLLM, a framework that builds relevant context dynamically and uses a provenance graph to identify which messages must be removed, achieving a high deletion rate while preserving utility.

By Olga Ohrimenko