EpiSEM-Bench: eight of ten models committed a prohibited action in 40%+ of tasks when a tool quietly dropped a safety-critical fact
AspireAI community · City University of Hong Kong, HKUST (Guangzhou) and CUHK-Shenzhen (arXiv)
EpiSEM-Bench, from researchers at City University of Hong Kong, HKUST (Guangzhou) and CUHK-Shenzhen, removes true but safety-critical facts from a tool's response and then checks what the agent does anyway: across 300 matched task pairs in six domains, eight of the ten evaluated models executed a prohibited operation in more than 40% of tasks under critical evidence omission, while GPT-6-Luna was the most robust at 21.0% and MiMo-V2.5-Pro the least at 88.0%. It also measures whether an agent recovers: given access to an independent audit source, unsafe execution fell for every model, yet the leader on omission safety, GPT-6-Luna, was not the leader on Paired Useful Recovery, and the paper's worked example shows the same $42,800 payment correctly escalating under a $30,000 limit and executing under a $50,000 limit. The limitation is that these are the authors' own measurements on ten serving configurations under a benchmark they designed, and the paper is explicit that 'no observed failure' is a bounded statement about the conditions they tested rather than a safety guarantee.
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