Worked on the freqtrade/freqtrade repository to enhance the robustness and developer experience of its WebSocket API. Focused on backend development using Python, the work introduced input validation for WebSocket requests, ensuring that invalid data types are caught early in the communication process. By implementing user-friendly error handling, the system now provides clear, actionable feedback to clients when incorrect request types are submitted. This approach not only improves reliability but also reduces support overhead by minimizing troubleshooting after deployment. The changes were supported by thorough testing and leveraged skills in API development and WebSocket programming to deliver a more resilient API interface.