Yusei Kaida focused on improving documentation quality within the giftee/design-system repository, specifically targeting the designTokens package. During this period, Yusei identified and corrected an inaccurate Japanese term in the README, replacing '携帯' with '形態' to better reflect the intended meaning regarding design token provisioning. This change, implemented using Markdown and leveraging strong documentation skills, enhanced clarity for both designers and developers. By ensuring terminology accuracy and maintaining high documentation standards, Yusei reduced potential onboarding confusion and support issues. The work demonstrated careful attention to cross-locale language nuances, though the scope was limited to a single, well-executed documentation fix.