{"schema":"https://ver.cy/schemas/card/1.0.0","id":"vr.tr.december-18","code":"thing-q2438","url":"https://ver.cy/models/thing/q2438/","name":"December 18","alternateNames":[],"kind":"thing","status":"published","version":"0.2.0-wave.3","language":"en","classifiers":{"family":"Thing Registry","category":"Cross-cutting context","entryKind":"thing","plane":"XCT","domain":["XCT.TME"],"industry":[],"navPath":"","tags":[],"facets":{}},"whatItIs":"December 18, day 352 (day 353 in leap years) of the year in the Gregorian calendar, with 13 days remaining in both common and leap years. December 18 is International Migrants Day and UN Arabic Language Day, the National Day of Qatar, Republic Day in Niger, and the anniversary of the certification and proclamation in 1865 of the ratification of the Thirteenth Amendment abolishing slavery in the United States, which was ratified on December 6, 1865.","purpose":"Let an agent handle December 18 as a calendar date with weekday computation, observances attributed to their traditions and sourced events.","scope":{"in":[],"out":[],"boundaries":[]},"distinguishingFeatures":["The eighteenth day of December","Weekday varies by year","Observances vary by place","Julian and Gregorian dates differ by 13 days in this era"],"structure":{"bundles":[{"id":"date","name":"Date","description":"Calendar facts.","layers":[{"id":"weekday","name":"Weekday","description":"Computation.","findings":[{"id":"weekday-finding","name":"Weekday","description":"Weekday.","questions":[{"text":"On which weekday does December 18 fall in this year?","kind":"measurement"},{"text":"Is it a leap year?","kind":"boundary"}]}]},{"id":"calendar","name":"Calendar","description":"Julian or Gregorian.","findings":[{"id":"calendar-finding","name":"Calendar","description":"Calendar system.","questions":[{"text":"Is the Julian or Gregorian calendar meant?","kind":"boundary"},{"text":"What is the equivalent date in the other calendar?","kind":"measurement"}]}]}]},{"id":"observances","name":"Observances","description":"Holidays.","layers":[{"id":"holiday","name":"Holiday","description":"Public holiday.","findings":[{"id":"holiday-finding","name":"Holiday","description":"Holiday status.","questions":[{"text":"Is December 18 a public holiday or observance here?","kind":"provenance"},{"text":"Which tradition or law sets it?","kind":"provenance"}]}]},{"id":"attribution","name":"Attribution","description":"Traditions.","findings":[{"id":"attribution-finding","name":"Attribution","description":"Attributed observances.","questions":[{"text":"Which countries or communities observe something on this date, according to them?","kind":"provenance"},{"text":"Is the observance attributed rather than assumed?","kind":"boundary"}]}]}]},{"id":"history","name":"History","description":"Past events.","layers":[{"id":"events","name":"Events","description":"On this day.","findings":[{"id":"events-finding","name":"Events","description":"Historical events.","questions":[{"text":"Which notable events happened on December 18, according to reliable sources?","kind":"provenance"},{"text":"Are dates given in the same calendar?","kind":"boundary"}]}]},{"id":"anniversaries","name":"Anniversaries","description":"Recurring.","findings":[{"id":"anniversaries-finding","name":"Anniversaries","description":"Anniversaries.","questions":[{"text":"Which anniversaries fall on this date this year?","kind":"provenance"},{"text":"Which are round numbers?","kind":"measurement"}]}]}]},{"id":"planning","name":"Planning","description":"Scheduling.","layers":[{"id":"countdown","name":"Countdown","description":"Days until.","findings":[{"id":"countdown-finding","name":"Countdown","description":"Countdown.","questions":[{"text":"How many days until the next December 18?","kind":"measurement"},{"text":"From which date?","kind":"definition"}]}]},{"id":"work","name":"Work","description":"Working day.","findings":[{"id":"work-finding","name":"Work","description":"Working day.","questions":[{"text":"Is it a working day for this organisation?","kind":"provenance"},{"text":"Do deadlines move?","kind":"boundary"}]}]}]}]},"agentConduct":{"may":["Give December 18 as day 352 of the Gregorian year, 353 in leap years.","Note International Migrants Day and UN Arabic Language Day, with sources."],"mustNot":["Present observances on December 18 as universally kept.","Use International Migrants Day content to stereotype migrants.","List on-this-day events without sources or mix calendar systems."],"requiresHuman":["Fixing year-end deadlines on this date for a person or organisation."]},"ethics":{"considerations":["Observances for migrants and languages touch on dignity and identity.","Accurate dates prevent false history."],"affectedParties":["Migrants","Arabic-speaking communities","Readers"]},"owners":{"steward":"Nobody owns the date; the public holds it in common.","roles":[],"masterSystems":[]},"relations":[{"target":"Q11185474","type":"parent","note":"registry parent class"},{"target":"December","type":"related","note":"month"},{"target":"December 17","type":"related","note":"date"},{"target":"calendar date","type":"related","note":"category"},{"target":"ISO 8601","type":"related","note":"notation"}],"interaction":{"identity":{"applicability":"required","items":["Vercy registry: vr.tr.december-18","Wikidata: Q2438 (https://www.wikidata.org/wiki/Q2438)","ISO 8601: --12-18 recurring date"]},"properties":{"applicability":"not-applicable","items":["day of year: 352 or 353 day - common year, leap year where different","days remaining: 13 days"]},"recognition":{"applicability":"optional","items":["Written 18 December or December 18","ISO format --12-18","Observances vary by country and tradition","A date on calendars."]},"capabilities":{"applicability":"required","items":["compute its weekday in a given year","check local and international observances","find sourced historical events","schedule events"]},"hazards":{"applicability":"required","items":["Assuming observances are universal","Unsourced on-this-day events","Mixing Julian and Gregorian dates"]},"interfaces":{"applicability":"required","items":["ISO 8601","National public holiday laws"]},"context":{"applicability":"required","items":["A calendar date for scheduling, holidays and anniversaries.","the recurring calendar date","specific dated days in given years"]}},"sources":[{"title":"Wikidata item Q2438: December 18","url":"https://www.wikidata.org/wiki/Q2438","note":"identity and sense of the item"},{"title":"Wikipedia: December 18","url":"https://en.wikipedia.org/wiki/December_18","note":"general description of the item"}],"openQuestions":["Should dated days be separate entries?","How should observances be linked?","How should events be sourced?"],"resources":{"spec":"/models/things/publications/thing-q2438/spec.json"},"provenance":{"origin":"thing registry research (pass 2)","builtFrom":["models/things/publications/thing-q2438/spec.json"],"providers":["Claude"],"researchStatus":"unreviewed","generatedAt":"2026-09-13T06:04:02Z","builder":"tools/build_cards.py@1.0.0"},"completeness":{"sections":{"classifiers":"filled","whatItIs":"filled","purpose":"filled","distinguishingFeatures":"filled","structure":"filled","agentConduct":"filled","ethics":"filled","owners":"filled","relations":"filled","interaction.identity":"filled","interaction.properties":"not-applicable","interaction.recognition":"filled","interaction.capabilities":"filled","interaction.hazards":"filled","interaction.interfaces":"filled","interaction.context":"filled","sources":"filled"},"notes":{"_gate":"Published through the thing publication gate 1.0 on 2026-10-07T10:10:29+00:00: completeness 1.00; sense: Wikidata description; 2 live sources; review by codex: pass","interaction.properties":"Plane XCT: no invented physical properties."},"score":1.0}}