Atropos: Predictive Early Termination and Model Hotswap Cut LLM Agent Costs for SWE Tasks

arXiv·medium signal

Atropos (arXiv 2604.15075) proposes a predictive early termination system for LLM-based software engineering agents that dynamically swaps between smaller and larger models based on task complexity signals. The approach improves cost-benefit trade-offs by stopping self-consistency sampling early when confident and escalating to larger models only when needed. For teams running agents at scale (SWE-bench, coding assistants), this is a practical cost optimization: use cheap models by default, escalate on detected difficulty, and stop sampling when confidence is sufficient.