Bruce Lee enhanced the UKGovernmentBEIS/control-arena repository by implementing range-based task evaluation in the Control Arena CLI. He introduced support for parsing START-END strings, converting user input into (start, end) pairs, and integrating this logic with the existing configuration framework. Using Python and leveraging skills in argument parsing and CLI development, Bruce’s work enabled users to specify precise subsets of tasks for evaluation, reducing manual configuration and aligning assessments with planning windows. He also addressed linting issues and resolved a reopened issue, contributing to code quality. This update improved workflow efficiency and provided more targeted performance analysis capabilities.