{"openapi":"3.1.0","info":{"title":"Calendar Systems","version":"1.0.0","description":"Date conversion and calendar facts for agents: Julian Day, Julian, Hebrew, Islamic tabular and Persian calendars, Chinese zodiac, moon phases and seasons. One call, one computed answer, no accounts or API keys. Machine-payable over x402.","x-guidance":"Calendar Systems: Date conversion and calendar facts for agents: Julian Day, Julian, Hebrew, Islamic tabular and Persian calendars, Chinese zodiac, moon phases and seasons. Use /julian-day for Julian Day and MJD, /julian-calendar for Julian versus Gregorian dates, /hebrew-calendar, /islamic-calendar and /persian-calendar for date conversion, /chinese-zodiac for the zodiac animal, element and Chinese New Year, /day-of-week for weekday and ISO week facts, /leap-year for leap rules by calendar, /moon-phase and /moon-calendar for lunar phases, /seasons for equinox and solstice times, and /age-profile for age conventions. 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