Disagree to Explore, Agree to Commit: Routing-Guided Test-Time Scaling for Software Agents

2026-08-22

AI Summary

研究通过路由指导的方法解决软件代理在测试时扩展困难的问题，提出Risa方法提高修复率。

Abstract

Software-engineering agents solve repository-level tasks through long, stochastic tool-use trajectories, and repeated attempts often find fixes missed by one run. Test-time scaling is difficult because patches lack canonical answer forms, while sibling actions from a shared prefix are correlated. We study whether native MoE router traces can guide steering and selection without an external judge or selection-time test execution. Our analysis shows that routing provides a robust behavioral role signal; token-granular readouts and decision-matched comparison sets turn it into effective control. We therefore introduce Risa (Routing-Informed Steering and Arbitration): within trajectories, routing encourages diverse exploration and controlled convergence during patch commitment; across separately sampled trajectories, agreement at informative patch positions selects a final candidate. We evaluate on SWE-bench Verified using open-weight sparse MoE agents across scales and reasoning-effort settings. Risa's routing arbitration raises the macro-average resolved rate from 44.9% under uniform sampling to 48.2% on the gpt-oss family, matching text consensus without answer-string matching, and it transfers to Qwen3.6, where it improves on uniform choice and matches text consensus on the full 500-task benchmark.

Problem

• Software-engineering agents
• test-time scaling
• routing
• patch commitment

Innovation

• Risa
• Routing-Informed Steering and Arbitration
• MoE router traces
• diverse exploration
• controlled convergence