{
  "vercy": "1.0-draft",
  "publication": {
    "status": "research-draft",
    "adjudicationStatus": "unreviewed",
    "publishableCanonical": false,
    "generatedAt": "2026-09-12T03:00:56Z",
    "providers": [
      "Claude"
    ],
    "breadth": "written by Claude from model knowledge without web access - no source was read, every claim is a lead to verify",
    "pass": 2,
    "wave": 2,
    "engine": "claude",
    "enrichment": {
      "pass": 3,
      "engine": "claude",
      "producedAt": "2026-10-05T23:55:00Z",
      "ingestedAt": "2026-10-05T20:53:47+00:00",
      "fields": [
        "agent_conduct",
        "ethics",
        "owners"
      ]
    },
    "gate": {
      "passed": true,
      "version": "1.0",
      "at": "2026-10-06T19:51:57+00:00",
      "evidence": [
        "completeness 1.00",
        "sense: Wikidata description",
        "2 live sources",
        "review by codex: pass"
      ]
    }
  },
  "metaModel": {
    "id": "THING-Q2524",
    "registryId": "vr.tr.april-20",
    "name": "April 20",
    "version": "0.2.0-wave.2",
    "entryKind": "thing",
    "family": "Thing Registry",
    "domain": [
      "XCT.TME"
    ],
    "status": "research-draft"
  },
  "canonicalUrl": "https://ver.cy/models/thing/q2524/",
  "model": {
    "registry_id": "vr.tr.april-20",
    "name": "April 20",
    "purpose": "Let an agent handle April 20 as a calendar date with weekday computation, observances attributed to their traditions and sourced events.",
    "definition": "April 20, day 110 (day 111 in leap years) of the year in the Gregorian calendar, with 255 days remaining in both common and leap years. Observances on this date vary by country and tradition; it is Chinese Language Day at the United Nations.",
    "what_it_is_for": "A calendar date for scheduling, holidays and anniversaries.",
    "affordances": [
      "compute its weekday in a given year",
      "check local and international observances",
      "find sourced historical events",
      "schedule events"
    ],
    "distinguishing_features": [
      "The twentieth day of April",
      "Weekday varies by year",
      "Observances vary by place",
      "Julian and Gregorian dates differ by 13 days in this era"
    ],
    "appearance": "A date on calendars.",
    "visual_identification": [
      "Written 20 April or April 20",
      "ISO format --04-20",
      "Observances vary by country and tradition"
    ],
    "physical_properties": [
      {
        "quantity": "day of year",
        "typical_range": "110 or 111",
        "unit": "day",
        "note": "common year, leap year where different"
      },
      {
        "quantity": "days remaining",
        "typical_range": "255",
        "unit": "days",
        "note": ""
      }
    ],
    "families_and_kinds": [
      "the recurring calendar date",
      "specific dated days in given years"
    ],
    "related_models": [
      {
        "relation": "is part of",
        "target": "April",
        "why": "month"
      },
      {
        "relation": "follows",
        "target": "April 19",
        "why": "date"
      },
      {
        "relation": "is a kind of",
        "target": "calendar date",
        "why": "category"
      },
      {
        "relation": "is expressed in",
        "target": "ISO 8601",
        "why": "notation"
      }
    ],
    "identifiers": [
      {
        "scheme": "ISO 8601",
        "value_or_pattern": "--04-20",
        "note": "recurring date"
      }
    ],
    "standards_and_regulation": [
      "ISO 8601",
      "National public holiday laws"
    ],
    "failure_modes_and_hazards": [
      "Assuming observances are universal",
      "Unsourced on-this-day events",
      "Mixing Julian and Gregorian dates"
    ],
    "in_scope": [],
    "out_of_scope": [],
    "characteristics": [],
    "agent_conduct": {
      "may": [
        "State the date's position in the Gregorian year and convert it to other calendars.",
        "Report observances on April 20, such as the United Nations Chinese Language Day, with sources."
      ],
      "must_not": [
        "Celebrate or promote extremist commemorations that some groups attach to April 20.",
        "Present a disputed or local observance as universal.",
        "Assign events to April 20 without checking calendar changes for historical dates."
      ],
      "requires_human": [
        "Scheduling events on the date for organisations that may find its associations sensitive."
      ]
    },
    "ethics": {
      "considerations": [
        "April 20 is marked by very different groups, some celebratory and some hateful; context matters.",
        "Anniversaries of attacks on this date are painful for survivors and families."
      ],
      "affected_parties": [
        "Survivors of violence remembered on the date",
        "Chinese language communities",
        "Event organisers"
      ]
    },
    "owners": {
      "steward": "The public: held in common; nobody owns a calendar date.",
      "master_systems": []
    }
  },
  "sources": [
    {
      "id": "wikidata",
      "title": "Wikidata item Q2524: April 20",
      "url": "https://www.wikidata.org/wiki/Q2524",
      "url_status": "live",
      "what_it_supports": "identity and sense of the item",
      "checked_by": "wikidata-api"
    },
    {
      "id": "wikipedia-en",
      "title": "Wikipedia: April 20",
      "url": "https://en.wikipedia.org/wiki/April_20",
      "url_status": "live",
      "what_it_supports": "general description of the item",
      "checked_by": "wikidata-api sitelink"
    }
  ],
  "structure": {
    "bundles": [
      {
        "id": "date",
        "name": "Date",
        "description": "Calendar facts.",
        "rationale": "Calendar arithmetic.",
        "layers": [
          {
            "id": "weekday",
            "name": "Weekday",
            "description": "Computation.",
            "findings": [
              {
                "id": "weekday-finding",
                "name": "Weekday",
                "description": "Weekday.",
                "questions": [
                  {
                    "text": "On which weekday does April 20 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.",
        "rationale": "Observances vary.",
        "layers": [
          {
            "id": "holiday",
            "name": "Holiday",
            "description": "Public holiday.",
            "findings": [
              {
                "id": "holiday-finding",
                "name": "Holiday",
                "description": "Holiday status.",
                "questions": [
                  {
                    "text": "Is April 20 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.",
        "rationale": "Events need sources.",
        "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 April 20, 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.",
        "rationale": "Dates drive plans.",
        "layers": [
          {
            "id": "countdown",
            "name": "Countdown",
            "description": "Days until.",
            "findings": [
              {
                "id": "countdown-finding",
                "name": "Countdown",
                "description": "Countdown.",
                "questions": [
                  {
                    "text": "How many days until the next April 20?",
                    "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"
                  }
                ]
              }
            ]
          }
        ]
      }
    ]
  },
  "openQuestions": [
    "Should dated days be separate entries?",
    "How should observances be linked?",
    "How should events be sourced?"
  ],
  "statistics": {
    "bundles": 4,
    "layers": 8,
    "findings": 8,
    "questions": 16
  }
}