Worked on the Kotlin/kotlinx.serialization repository, focusing on improving error handling for JSON parsing. Addressed a specific bug where the error message for invalid trailing commas referenced an incorrect configuration option, updating it from allowTrailingCommas to allowTrailingComma to match the actual setting. This change clarified user guidance and reduced potential confusion when configuring JSON parsing behavior. Utilized Kotlin and applied skills in configuration management and error handling to ensure the fix was precise and aligned with existing code standards. The work maintained high commit quality and contributed to a more intuitive developer experience without introducing new features during the period.