Worked on backend development for the openai/openai-agents-python repository, focusing on improving error handling and input validation in the handoff function. Addressed a critical bug by replacing assertions with UserError exceptions, ensuring that invalid user inputs are communicated clearly and consistently. This approach centralized error management and removed hard assertions from the production path, enhancing code maintainability and reducing user confusion. The solution was linked to relevant issues and pull requests for traceability. Utilized Python and unit testing to verify the changes, demonstrating a methodical approach to backend reliability and user-facing error reporting within the project’s codebase.