Beyond Compaction: Structured Context Eviction for Long-Horizon Agents

The article introduces the Context Window Lifecycle (CWL), a novel context-management scheme designed for long-horizon LLM agents, allowing them to operate with an effectively unbounded working horizon. CWL employs a semantically-aware eviction policy that prioritizes the retention of relevant user interactions and active reasoning context while systematically removing less critical action episodes, demonstrating no degradation in task accuracy across 89 sequential tasks with a token budget of 80 million tokens. This approach addresses key limitations of traditional compaction methods, such as lossiness and causal structure destruction, making it a significant advancement for practitioners focused on enhancing the efficiency and effectiveness of LLMs in complex, prolonged tasks.