GroundBench benchmark aims to pinpoint where vision-language models fail on affordance tasks

A new arXiv paper introduces GroundBench, described as a factorized, counterfactual benchmark for identifying the specific points at which vision-language models break down on affordance tasks. The work cites a companion evaluation in which explicitly naming the target part in a manipulation prompt improved action accuracy by 0.32 to 0.63 across eight vision-language models, and no model exceeded a constant baseline before that part was named. The benchmark is intended to isolate these failures rather than report only aggregate scores.