SmellBench Refactoring (OpenHands) - Localization Accuracy: leaderboard

SmellBench (2026, code refactoring) injects code smells into clean code from seven real Python repositories and asks a code agent to remove them; it is unrelated to the SmellBench board on architectural smell repair. This board is the percentage of cases in which the agent edits the class or method that holds the injected smell, over 294 cases with the OpenHands agent harness; higher is better.

Metric: Localization accuracy (%): the edited class or method matches the ground-truth refactoring target; 294 injected-smell refactoring cases (7 smell types, 3 difficulty levels, guided and targeted instructions) in 7 real Python repositories, run once in the Harbor Docker framework with a 20-minute budget, OpenHands agent harness; higher is better. Source: arxiv.org. Saturation forecast: Estimated already saturated. 6 models tracked.

Top models

#ModelScoreOverall rank
1Claude Sonnet 4.584.01#250
2GPT-5 Mini77.21#348
3Qwen 3 Coder 480B A35B Instruct74.56#643
4DeepSeek V3.272.24#406
5Qwen 3 Coder 30B A3B Instruct70.67#972
6Gemini 2.5 Flash66.67#453

No result here: #1 Claude Fable 5.2, #2 Gemini 4 Carbon, #5 Claude Opus 5.5.

Interactive version: theaggregate.ai/benchmark?slug=smellbench-refactoring-openhands-localization-accuracy · How It Works · Data refreshed daily, snapshot 2026-11-13.