Terminal-Bench 4.1 Released with Hardened Verifiers Against Reward Hacking

Terminal-Bench 4.1 is released with improved verifiers designed to resist reward hacking, and regrading TB 4.0 with the new verifiers required $0 in additional inference cost. Only about 1.16% of 11,550 trials changed score, and all 35 agents' updated scores remain within their original TB 4.0 95% confidence intervals.