aiqbench analysis
CompactionRL addresses the critical bottleneck of finite context windows in long-horizon agentic LLMs by integrating summary generation directly into the reinforcement learning pipeline. This method allows agents to maintain performance on complex coding tasks like SWE-bench while operating within compressed contexts, offering a practical pathway for scaling autonomous AI systems beyond current memory limits.
CompactionRL: Reinforcement Learning with Context Compaction for Long-Horizon Agents
arXiv:2607.05378v2 Announce Type: replace Abstract: Long-horizon agentic LLMs are increasingly limited by finite context windows, as extended interaction trajectories can exceed the maximum context length before a task is completed. Context compaction offers a natural solution by summarizing previous interaction states and continuing the rollout under a compressed context, but incorporating compaction into reinforcement learning remains underexplored. We propose CompactionRL, a reinforcement learning strategy to train long-horizon agentic LLMs with context compaction. Our approach jointly optimizes task execution and summary generation with token-level loss normalization and cross-segment generalized advantage estimation. This design enables the LLM agents to learn from compacted long-horizon trajectories. We train CompactionRL on top of open models and observe consistent performance gains on agentic coding tasks. CompactionRL enables the open GLM-4.5-Air model (106B-A12B) to achieve Pass@1 scores of 66.4% on SWE-bench Verified and 26.2% on Terminal-Bench 2.0, exceeding the base model under inference-time compaction by 6.6 and 4.9 points, respectively. Built upon GLM-4.7-Flash (30B-A3B), CompactionRL improves Pass@1 by 5.5 and 6.7 points against the base model, reaching 56.0% on SWE-bench Verified and 20.2% on Terminal-Bench 2.0. CompactionRL is thus deployed in the RL pipeline for training the open GLM-5.2 model (750B-A40B).
Abstract:Long-horizon agentic LLMs are increasingly limited by finite context windows, as extended interaction trajectories can exceed the maximum context length before a task is completed. Context compaction offers a natural solution by summarizing previous interaction states and continuing the rollout under a compressed context, but incorporating compaction into reinforcement learning remains underexplored. We propose CompactionRL, a reinforcement learning strategy to train long-horizon agentic LLMs with context compaction. Our approach jointly optimizes task execution and summary generation with token-level loss normalization and cross-segment generalized advantage estimation. This design enables the LLM agents to learn from compacted long-horizon trajectories. We train CompactionRL on top of open models and observe consistent performance gains on agentic coding tasks. CompactionRL enables the open GLM-4.5-Air model (106B-A12B) to achieve Pass@1 scores of 66.4% on SWE-bench Verified and 26.2% on Terminal-Bench 2.0, exceeding the base model under inference-time compaction by 6.6 and 4.9 points, respectively. Built upon GLM-4.7-Flash (30B-A3B), CompactionRL improves Pass@1 by 5.5 and 6.7 points against the base model, reaching 56.0% on SWE-bench Verified and 20.2% on Terminal-Bench 2.0. CompactionRL is thus deployed in the RL pipeline for training the open GLM-5.2 model (750B-A40B).
Machine Learning (cs.LG)
arXiv:2607.05378 [cs.LG]
(or arXiv:2607.05378v2 [cs.LG] for this version)
https://doi.org/10.48550/arXiv.2607.05378 Focus to learn more arXiv-issued DOI via DataCite
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