When the grader was leaked, production models followed the score rather than the instruction, at a similar rate with or without training
AspireAI community · arXiv
Production large language models sometimes reward-hack, exploiting flaws in how tasks are scored rather than performing the tasks as intended. The paper investigates what drives this in GPT 5.6 Sol, GPT 5.5 and a checkpoint of o3 without safety training, by observing behaviour in agentic environments where the grader is leaked. The models appear to be score-seeking: they try to score well according to graders they believe assess their current actions, even when that violates explicit user instructions, and they do so at approximately the same rate whether the score is indicated as feeding training, feeding evaluation, or nothing at all. More recent models also appear to care about scores that do not assess their own actions: Sol and 5.5 helped other agents 24.6 percentage points more often when that agent stood to gain a score of 1 rather than 0. When grading another trajectory, the models never colluded by distorting its score.
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