{ "model": { "rank": 5399, "code": "thing-q205892", "model_id": "vr.tr.calendar-date", "name": "calendar date", "purpose": "Let an agent handle dates with their calendar, precision, time zone dependence and format, and avoid the common errors of ambiguous or converted dates.", "family": "Thing Registry", "category": "Cross-cutting context", "status": "research-draft", "kind": "thing", "plane": "XCT", "domain": "XCT.TME", "industry": "", "version": "", "url": "/models/thing/q205892/", "tier": 2, "score": 67, "payload": { "layer": "wikidata", "aliases": [ "date of death", "date of birth", "best before date", "expiration date", "butsumetsu", "date of death of author(s)", "unknown vital dates", "date of birth of author", "accession date", "prefectural citizens' day", "sacred month", "date of preface", "bicentennial", "Gifaataa", "The Glass of Reason", "sesquicentennial", "anniversary", "semiquincentennial", "anniversary of the founding", "Wikivoyage's 10th birthday", "death anniversary", "semicentennial", "cultural anniversary", "jubilee", "Celebrating 700 years of the Swiss Confederation", "Yom Hillula", "centennial", "Wikidata birthday", "Ennichi", "Vietnamese Women's Day", "commemorative day", "world day", "Patriotism Memorial", "Urs", "diamond jubilee", "silver jubilee", "ruby jubilee", "Zentenarium", "sapphire jubilee", "platinum jubilee" ], "aliasCount": 809, "merged": 809, "knownIn": 67, "facets": null, "markers": [], "lexicalClass": "", "senseRank": null, "alsoRegisteredAs": null, "source": { "dataset": "wikidata", "item": "Q205892", "url": "https://www.wikidata.org/wiki/Q205892", "license": "CC0 1.0" } }, "research": { "vercy": "1.0-draft", "publication": { "status": "research-draft", "adjudicationStatus": "unreviewed", "publishableCanonical": false, "generatedAt": "2026-09-11T04:26:34Z", "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": 1, "engine": "claude" }, "metaModel": { "id": "THING-Q205892", "registryId": "vr.tr.calendar-date", "name": "calendar date", "version": "0.2.0-wave.1", "entryKind": "thing", "family": "Thing Registry", "domain": [ "XCT.TME" ], "status": "research-draft" }, "canonicalUrl": "https://ver.cy/models/thing/q205892/", "model": { "registry_id": "vr.tr.calendar-date", "name": "calendar date", "purpose": "Let an agent handle dates with their calendar, precision, time zone dependence and format, and avoid the common errors of ambiguous or converted dates.", "definition": "A particular day identified within a calendar system, written as a combination of year, month and day or an equivalent reckoning.", "what_it_is_for": "Identifying days, for records, deadlines, events and history.", "affordances": [ "write and parse it, in a defined format", "convert it between calendars", "compute intervals between dates", "record its precision, when only the year or month is known" ], "distinguishing_features": [ "Belongs to a calendar system: Gregorian, Julian, Islamic, Hebrew and others", "Has a precision: day, month, year, decade or circa", "Depends on time zone when derived from an instant", "Distinct from a time of day and from a time interval" ], "appearance": "Text such as 2026-09-11, 11/09/2026 or 11 September 2026; the same day is written differently across locales.", "visual_identification": [ "Year, month and day components in some order", "ISO 8601 format YYYY-MM-DD is unambiguous; slash formats are not", "Date-of-birth, expiry and best-before dates are typed uses of the same concept" ], "physical_properties": [], "families_and_kinds": [ "by calendar: Gregorian, Julian, Islamic, Hebrew, Chinese, Persian and others", "by precision: exact day, month, year, approximate", "by role: date of birth, date of death, expiry, effective date" ], "related_models": [ { "relation": "is part of", "target": "calendar", "why": "meaningful only within a calendar system" }, { "relation": "names", "target": "day", "why": "a date names one day" }, { "relation": "is confused with", "target": "timestamp", "why": "a timestamp is an instant; a date is a whole day in a place" }, { "relation": "has role", "target": "date of birth or expiry date", "why": "typed uses with their own rules" } ], "identifiers": [ { "scheme": "ISO 8601", "value_or_pattern": "YYYY-MM-DD", "note": "standard representation" }, { "scheme": "Julian Day Number", "value_or_pattern": "integer day count", "note": "calendar-independent count" } ], "standards_and_regulation": [ "ISO 8601 date and time representations", "RFC 3339 for internet timestamps", "Extended Date/Time Format (EDTF) for uncertain dates" ], "failure_modes_and_hazards": [ "Day-month order ambiguity, which silently swaps dates", "Off-by-one day errors from time zone conversion", "Julian and Gregorian confusion for historical dates", "False precision when only the year is known" ], "in_scope": [], "out_of_scope": [], "characteristics": [] }, "sources": [], "structure": { "bundles": [ { "id": "calendar-and-precision", "name": "Calendar and precision", "description": "Which calendar and how exact.", "rationale": "A date without its calendar and precision is ambiguous.", "layers": [ { "id": "calendar", "name": "Calendar", "description": "The calendar system.", "findings": [ { "id": "calendar-finding", "name": "Calendar system", "description": "The calendar the date belongs to.", "questions": [ { "text": "Which calendar is this date expressed in?", "kind": "definition" }, { "text": "What is its equivalent in the Gregorian calendar?", "kind": "measurement" } ] } ] }, { "id": "precision", "name": "Precision", "description": "Day, month, year or approximate.", "findings": [ { "id": "precision-finding", "name": "Precision level", "description": "How precisely the date is known.", "questions": [ { "text": "How precisely is this date known?", "kind": "measurement" }, { "text": "How should uncertainty be displayed?", "kind": "action" } ] } ] } ] }, { "id": "format-and-parsing", "name": "Format and parsing", "description": "Writing and reading dates.", "rationale": "Most date errors come from formats.", "layers": [ { "id": "format", "name": "Format", "description": "Written representation.", "findings": [ { "id": "format-finding", "name": "Format used", "description": "The format and locale.", "questions": [ { "text": "In which format is this date written?", "kind": "definition" }, { "text": "Is the order of day and month unambiguous?", "kind": "boundary" } ] } ] }, { "id": "parsing", "name": "Parsing", "description": "Reading dates reliably.", "findings": [ { "id": "parsing-finding", "name": "Parsing rules", "description": "How the date is parsed.", "questions": [ { "text": "How should this text be parsed into a date?", "kind": "action" }, { "text": "What should happen when the format is ambiguous?", "kind": "action" } ] } ] } ] }, { "id": "time-zones", "name": "Time zones", "description": "Dates from instants.", "rationale": "The same instant falls on different dates in different places.", "layers": [ { "id": "derivation", "name": "Derivation", "description": "Converting an instant to a date.", "findings": [ { "id": "derivation-finding", "name": "Zone used", "description": "The time zone used.", "questions": [ { "text": "In which time zone was this date derived?", "kind": "provenance" }, { "text": "Could the date differ in another relevant zone?", "kind": "boundary" } ] } ] }, { "id": "deadlines", "name": "Deadlines", "description": "Dates as deadlines.", "findings": [ { "id": "deadlines-finding", "name": "Deadline interpretation", "description": "When a date deadline ends.", "questions": [ { "text": "When exactly does a deadline on this date expire?", "kind": "boundary" }, { "text": "Which time zone governs it?", "kind": "definition" } ] } ] } ] }, { "id": "role-and-use", "name": "Role and use", "description": "What the date is for.", "rationale": "Typed dates carry rules: a date of birth is personal data, an expiry date has consequences.", "layers": [ { "id": "role", "name": "Role", "description": "Birth, death, expiry, effective.", "findings": [ { "id": "role-finding", "name": "Date role", "description": "The role and its rules.", "questions": [ { "text": "What role does this date play in the record?", "kind": "definition" }, { "text": "What rules follow from that role?", "kind": "boundary" } ] } ] }, { "id": "protection", "name": "Protection", "description": "Personal data concerns.", "findings": [ { "id": "protection-finding", "name": "Data protection", "description": "Whether it is personal data.", "questions": [ { "text": "Is this date personal data, such as a date of birth?", "kind": "boundary" }, { "text": "What limits apply to sharing it?", "kind": "action" } ] } ] } ] } ] }, "openQuestions": [ "Should the registry require a calendar and precision for every date?", "How should uncertain and approximate dates be recorded?", "Which role types of date need their own entries?" ], "statistics": { "bundles": 4, "layers": 8, "findings": 8, "questions": 16 } }, "draft": { "generator": "vr.draft.v3", "status": "draft-generated", "researched": false, "archetype": "abstract concept", "method": "Written from the archetype playbook - what this kind of thing needs beyond identity and provenance - and from the structure that recurred across 6,333 models already researched by two engines. Applied to this entry by rule. No source was read for this thing and no claim here is researched. This entry carries no facets of its own, so they were inferred from its domain - a guess about a whole domain applied to one thing.", "facetsInferred": true, "nextPass": "A researcher replaces this draft with a sourced specification. Treat every sentence below as a proposal to argue with.", "purpose": "Give an agent a durable, checkable way to recognise a calendar date, record what state it is in, and decide what may be done with it.", "whatItIs": "Let an agent handle dates with their calendar, precision, time zone dependence and format, and avoid the common errors of ambiguous or converted dates.", "characteristics": { "substance": "abstract", "origin": "conceptual", "agency": "inert" }, "whatYouCanDoWithIt": [ "observed and measured" ], "distinguishingFeatures": [ "Names folded into this entry, which a task may need to split apart again: date of death, date of birth, best before date, expiration date, butsumetsu, date of death of author(s), unknown vital dates, date of birth of author, accession date, prefectural citizens' day, sacred month, date of preface.", "809 finer distinctions are held as aliases rather than separate entries, because telling them apart needs a task that asks for it.", "Described in 67 Wikipedia languages, which is a measure of how widely the thing is known, not of how important it is." ], "openQuestionsForResearch": [ "Which of the bundles below does a real task actually need, and which are ceremony?", "What does this thing have that the facets do not capture at all?", "Which neighbouring kind is most often confused with a calendar date, and on what evidence are they told apart?" ], "whatItIsMadeOf": "an abstraction with no physical instance", "physicalCharacter": [ "Does nothing on its own; everything it does, something else did to it.", "These come from the domain this entry sits in rather than from the entry itself, so treat them as a first guess about the whole domain applied to one thing." ], "whatCanBeDoneWithIt": [ "observe it, measure it, record its state" ], "howItIsRecognised": [ "Nothing to see. What is recognised is an instance of it, and which instances count is exactly what is argued about." ], "relatedModels": [ { "relation": "covers", "note": "Finer kinds folded into this entry because telling them apart needs a task that asks for it. Each is a model waiting to be split out when one does.", "targets": [ "date of death", "date of birth", "best before date", "expiration date", "butsumetsu", "date of death of author(s)", "unknown vital dates", "date of birth of author", "accession date", "prefectural citizens' day", "sacred month", "date of preface" ] } ], "standing": "Described in 67 Wikipedia languages, which measures how widely it is written about rather than how important or how common it is. 809 finer distinctions are held inside this entry as names rather than as separate models.", "structure": { "bundles": [ { "id": "identity-and-classification", "name": "Identity, naming and classification", "description": "How an agent tells one calendar date from another, and a calendar date from things that resemble it.", "rationale": "Recognition comes before every other claim. Without stable identity nothing else in the model can be trusted to be about the same thing twice.", "layers": [ { "id": "naming-and-identifiers", "name": "Names and identifiers", "description": "The names this thing goes by and the identifiers that survive translation and time.", "findings": [ { "id": "preferred-name-and-aliases", "name": "Preferred name, aliases and local names", "description": "Which name to use, which names mean the same thing, and which merely sound similar.", "questions": [ { "id": "preferred-name-and-aliases-q01", "text": "What identifies and describes the name of a calendar date, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "preferred-name-and-aliases-q02", "text": "Who or what asserted this about the name of a calendar date, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "preferred-name-and-aliases-q03", "text": "What may an agent decide or do once the name of a calendar date is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] }, { "id": "stable-identifiers", "name": "Stable identifiers and external keys", "description": "Identifiers that keep pointing at this kind of thing across systems and languages.", "questions": [ { "id": "stable-identifiers-q01", "text": "What identifies and describes an identifier for a calendar date, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "stable-identifiers-q02", "text": "Who or what asserted this about an identifier for a calendar date, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "stable-identifiers-q03", "text": "What may an agent decide or do once an identifier for a calendar date is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] } ] }, { "id": "classification-and-granularity", "name": "Classification and granularity", "description": "Where a calendar date sits among kinds, and how finely a task needs to cut it.", "findings": [ { "id": "kind-and-parents", "name": "Kind, parents and neighbouring kinds", "description": "The classes this thing belongs to and the ones it is next to.", "questions": [ { "id": "kind-and-parents-q01", "text": "What identifies and describes the kind of a calendar date, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "kind-and-parents-q02", "text": "Who or what asserted this about the kind of a calendar date, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "kind-and-parents-q03", "text": "What may an agent decide or do once the kind of a calendar date is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] }, { "id": "distinguishing-features", "name": "Distinguishing features", "description": "What separates a calendar date from the things most often confused with it.", "questions": [ { "id": "distinguishing-features-q01", "text": "What identifies and describes what distinguishes a calendar date, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "distinguishing-features-q02", "text": "Who or what asserted this about what distinguishes a calendar date, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "distinguishing-features-q03", "text": "What may an agent decide or do once what distinguishes a calendar date is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] } ] } ] }, { "id": "state-and-lifecycle", "name": "State and lifecycle", "description": "The states a calendar date passes through and the events that move it between them.", "rationale": "Most decisions about a thing depend on what state it is in now, which is a claim with a time on it, not a property.", "layers": [ { "id": "lifecycle-stages", "name": "Lifecycle stages", "description": "From coming into existence to ceasing to be one of these.", "findings": [ { "id": "stages-and-transitions", "name": "Stages and transitions", "description": "The stages worth naming and what moves a calendar date between them.", "questions": [ { "id": "stages-and-transitions-q01", "text": "What identifies and describes the lifecycle of a calendar date, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "stages-and-transitions-q02", "text": "Who or what asserted this about the lifecycle of a calendar date, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "stages-and-transitions-q03", "text": "What may an agent decide or do once the lifecycle of a calendar date is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] } ] }, { "id": "observations-and-status", "name": "Observations and current status", "description": "What is observed about a calendar date, how often and by whom.", "findings": [ { "id": "observation-record", "name": "Observation record", "description": "How an observation of a calendar date is recorded so that it can be superseded rather than overwritten.", "questions": [ { "id": "observation-record-q01", "text": "What identifies and describes an observation of a calendar date, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "observation-record-q02", "text": "Who or what asserted this about an observation of a calendar date, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "observation-record-q03", "text": "What may an agent decide or do once an observation of a calendar date is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] } ] } ] }, { "id": "definitions-in-contest", "name": "Definitions and who holds them", "description": "What calendar date is taken to mean, and by whom.", "rationale": "When a field disagrees about a concept, the disagreement is the content. A model that picks one definition silently destroys the information.", "layers": [ { "id": "competing-definitions", "name": "Competing definitions", "description": "The main readings and the traditions behind them.", "findings": [ { "id": "definition-map", "name": "Definitions and their holders", "description": "Each definition with the school or body that holds it.", "questions": [ { "id": "definition-map-q01", "text": "Which definitions of calendar date are in use, and which tradition or body holds each?", "kind": "definition" }, { "id": "definition-map-q02", "text": "What turns on the difference between them in practice?", "kind": "boundary" } ] } ] }, { "id": "operationalisation", "name": "Operationalisation", "description": "How it is measured or applied when it has to be.", "findings": [ { "id": "operational-record", "name": "Measures and proxies", "description": "Instruments and indicators used to stand in for it.", "questions": [ { "id": "operational-record-q01", "text": "How is calendar date operationalised or measured in practice, and by what instrument?", "kind": "measurement" }, { "id": "operational-record-q02", "text": "What does that operationalisation leave out, and when does that matter?", "kind": "boundary" } ] } ] } ] }, { "id": "instances-and-use", "name": "Instances, use and consequence", "description": "What counts as an instance of calendar date and what follows from calling something that.", "rationale": "Applying a concept is an act with consequences, so a model must say what the label licenses and what it does not.", "layers": [ { "id": "instances", "name": "What counts as an instance", "description": "Clear cases, borderline cases and non-cases.", "findings": [ { "id": "instance-tests", "name": "Tests for an instance", "description": "What would settle whether something falls under it.", "questions": [ { "id": "instance-tests-q01", "text": "What would settle whether something is an instance of calendar date?", "kind": "boundary" }, { "id": "instance-tests-q02", "text": "Which borderline cases are argued about, and on what grounds?", "kind": "definition" } ] } ] }, { "id": "consequence", "name": "Consequence of application", "description": "Rights, duties or decisions that follow from the label.", "findings": [ { "id": "consequence-record", "name": "What the label licenses", "description": "What an agent may do once something is classified this way.", "questions": [ { "id": "consequence-record-q01", "text": "What follows practically once something is treated as calendar date?", "kind": "action" }, { "id": "consequence-record-q02", "text": "What must an agent not infer from the label alone?", "kind": "action" } ] } ] } ] }, { "id": "provenance-and-evidence", "name": "Provenance, evidence and time", "description": "Where every claim about a calendar date came from and when it held.", "rationale": "A claim without a source and a time cannot be superseded, only overwritten, and an agent that overwrites loses the ability to explain itself.", "layers": [ { "id": "source-and-authority", "name": "Source and authority", "description": "Who said it, on what evidence, and how strongly.", "findings": [ { "id": "claim-provenance", "name": "Claim provenance and confidence", "description": "The authority behind each claim about a calendar date and how confident it is.", "questions": [ { "id": "claim-provenance-q01", "text": "What identifies and describes a claim about a calendar date, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "claim-provenance-q02", "text": "Who or what asserted this about a claim about a calendar date, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "claim-provenance-q03", "text": "What may an agent decide or do once a claim about a calendar date is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] } ] }, { "id": "time-and-versions", "name": "Time, versions and supersession", "description": "When a claim was true, when it was learnt, and what replaced it.", "findings": [ { "id": "validity-and-supersession", "name": "Validity period and supersession", "description": "How an old claim about a calendar date is retired without being erased.", "questions": [ { "id": "validity-and-supersession-q01", "text": "What identifies and describes the validity of a claim about a calendar date, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "validity-and-supersession-q02", "text": "Who or what asserted this about the validity of a claim about a calendar date, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "validity-and-supersession-q03", "text": "What may an agent decide or do once the validity of a claim about a calendar date is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] } ] } ] } ] }, "statistics": { "bundles": 5, "layers": 10, "findings": 12, "questions": 32 } } } }