Terminal-Bench 4.0 released as a new major version of the continuous benchmark

The Terminal-Bench team published version 4.0 of its command-line agent benchmark on August 28, 2026, a month after announcing that it would be maintained as a continuous benchmark with semantic versioning. The release removed eight tasks, fixed nineteen, and set a flat eight-hour agent timeout for every task; it is a major version because these changes require re-running trials. It runs through the Harbor framework.123