Same Actions, Different Outcomes: The Cost of Tool-Schema Bias
TL;DR for operators Changing how an agent calls tools can change its task success even when the underlying operations remain identical. In a controlled study, one model’s success fell from 78.5% to zero after tools were consolidated into a particular interface representation, then recovered to 75.2% under another merged representation. Across nine main open-weight models, fully merging tools reduced success by a median of 19 percentage points. ...