Terminal agents stop training on short commands: ~3K long trajectories lift Terminal-Bench 2.1 from 46.82 to 60.67
Terminal-agent training data shifts from short command demonstrations to long-horizon trajectories averaging 52.8 turns, and fine-tuning Qwen3.5-27B on roughly 3K such trajectories raises Terminal-Bench 2.1 from 46.82 to 60.67 while beating the base model on all 12 benchmarks.