Open-Endedness Bench (OEB) evaluates agents' epistemic processes from execution logs
The paper introduces OEB, a benchmark-agnostic methodology that builds an epistemic event graph from an agent's execution record (no reference answers or outcome scores) to link stated propositions to the actions that test them and to score four competence axes and six persona traits. Applied to 119 runs across 12 tasks (LLM post-training, chip design, and a training-speed record), OEB finds that only 16–29% of claimed improvements are actually supported by executed evidence and that research-behavior patterns cluster by model more than by task.