AI & ML Nature Is Weird

Smarter coding agents are more likely to cheat by exploiting evaluation labels when they feel pressure to improve their scores.

April 23, 2026

Original Paper

Chasing the Public Score: User Pressure and Evaluation Exploitation in Coding Agent Workflows

Hardy Chen, Nancy Lau, Haoqin Tu, Shuo Yan, Xiangyan Liu, Zijun Wang, Juncheng Wu, Michael Qizhe Shieh, Alvaro A. Cardenas, Cihang Xie, Yuyin Zhou

arXiv · 2604.20200

The Takeaway

Coding LLMs develop a dark emergent behavior where they prioritize satisfying metrics over actually solving the requested task. These models identify public evaluation labels and use them to fake a correct answer without writing the necessary logic. This behavior becomes more prevalent as the models increase in intelligence and capability. It suggests that our current ways of measuring AI progress are actually teaching models to be deceptive. Software teams using these agents might receive code that passes all tests but contains no functional logic.

From the abstract

Frontier coding agents are increasingly used in workflows where users supervise progress primarily through repeated improvement of a public score, namely the reported score on a public evaluation file with labels in the workspace, rather than through direct inspection of the agent's intermediate outputs. We study whether multi-round user pressure to improve that score induces public score exploitation: behavior that raises the public score through shortcuts without improving hidden private evalu