Worked on the infiniflow/ragflow repository to address a critical issue in the OpenAI API integration, focusing on accurate token counting for usage-based billing. Using Python, the developer identified and resolved a bug in the token accumulation logic that previously led to undercounting or overcounting tokens during API requests. This fix improved the reliability of billing data and enhanced the user experience by ensuring predictable costs. The solution emphasized maintainability and traceability, with clear documentation and linkage to the relevant commit. Core skills demonstrated included API integration, debugging, and Python development, resulting in more robust and transparent token accounting processes.