Keith S. Thompson enhanced the llvm/llvm-project repository by improving the documentation for the Clang-Tidy switch-missing-default-case check. He focused on clarifying how switch statements behave when a default case is omitted and unhandled values are encountered, addressing a common source of confusion for developers. Using RST for documentation and leveraging his skills in technical writing, Keith delivered a documentation-only update that aligns with existing checks without requiring code changes. This work deepened the explanation of the check’s behavior, helping to streamline onboarding and improve developer understanding, though it did not involve direct feature development or bug fixes in the codebase.