Saju

This gives Claude access to Korean Saju (Four Pillars) astrology calculations based on birth date and time. You can generate complete birth charts showing the heavenly stems and earthly branches across year, month, day, and hour pillars, identify someone's Day Master element, analyze their Five Elements balance, and check compatibility between two people. Reach for this when you're building apps that need traditional East Asian astrology readings or want to explore how birth time correlates with elemental personality types in the Korean system. The calculations follow classical Saju principles, so it's useful for cultural applications, divination tools, or anyone curious about this branch of astrological practice.