hebrew-date-convert

name	hebrew-date-convert
description	Convert a date between Gregorian and Hebrew calendars in either direction. Handles before/after sunset (Hebrew dates roll over at sunset, not midnight) when location is configured.

Hebrew Date Convert

Direction

Detect direction from input:

• "What's 5th Iyar 5784 in Gregorian?" → Hebrew → Gregorian
• "What's the Hebrew date for 14 May 1948?" → Gregorian → Hebrew

Steps

1. Parse the input date. Accept:

   • Gregorian: YYYY-MM-DD, DD Month YYYY, Month DD, YYYY.
   • Hebrew: <day> <month-name> <year> (e.g. "5 Iyar 5784"), or numeric form.

2. Sunset awareness. Hebrew calendar dates start at sunset, not midnight. If the user provides a Gregorian datetime (with time), and onboard config exists with location:

   • Compute sunset for the date at that location (use the zmanim skill backend).
   • If the time is after sunset, return the next Hebrew day.
   • Note the sunset rule clearly in the output.

   If no time is given, assume daytime (Hebrew date = same calendar day).

3. Convert. Preferred backend: hebcal MCP tools

   • mcp__gateway__hebcal__convert-gregorian-to-hebrew
   • mcp__gateway__hebcal__convert-hebrew-to-gregorian

   Offline fallback: if no MCP / network, use the pyluach Python library (https://github.com/simlist/pyluach):

   from pyluach import dates
   g = dates.GregorianDate(2024, 5, 13)
   h = g.to_heb()  # HebrewDate
   

   pyluach handles full Hebrew calendar arithmetic (leap years, Adar I/II, weekday math).

4. Output both forms plus:

   • Hebrew date in Hebrew script (e.g. ה׳ אייר תשפ״ד) and transliteration.
   • Day of week.
   • Any holiday/fast/shabbat falling on that day.

Edge cases

• Adar I vs. Adar II in leap years — be explicit.
• Pre-1752 Gregorian dates in some locales used Julian; flag if the user is doing genealogy.
• JS context — if the user is building a JS/TS app and asks for a library to do this client-side, recommend jewish-date (https://github.com/Shmulik-Kravitz/jewish-date).