{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://schema.govfresh.com/v1/_core/boundary.schema.json",
  "title": "Boundary",
  "description": "The extent of a governed area over a period of time.",
  "type": "object",
  "properties": {
    "@context": {},
    "@id": {"type": "string", "format": "iri", "description": "This boundary's own dereferenceable identifier."},
    "@type": {"const": "Boundary", "description": "Always `Boundary` - a separate, citable entity rather than a field on the jurisdiction, because boundaries change and the change matters: wards are redrawn, municipalities annex and merge, electoral districts are reapportioned. A 2022 contest was fought on the 2022 boundary, and a budget line or permit attributed to an area is anchored to the boundary in force at the time. Attaching a single current geometry to a `Jurisdiction` silently rewrites history."},
    "name": {"type": "string", "description": "A human-readable label for this boundary, e.g. 'Ward 3 (2022)'."},
    "boundaryOf": {
      "$ref": "reference.schema.json",
      "description": "The `Jurisdiction` this is the extent of."
    },
    "geometry": {"$ref": "geometry.schema.json", "description": "The `Geometry` describing this boundary's shape."},
    "validFrom": {"type": "string", "format": "date", "description": "When this extent took effect."},
    "validUntil": {
      "type": "string", "format": "date",
      "description": "When it ceased to apply. Absent means current. A superseded boundary is retained, not deleted - it is what historical records were drawn against."
    },
    "authoritative": {
      "type": "boolean",
      "description": "Whether this is the legally definitive extent, as opposed to a published rendering of it."
    },
    "supersedes": {"$ref": "reference.schema.json", "description": "The `Boundary` this replaced."},
    "identifier": {"type": "array", "items": {"$ref": "identifier.schema.json"}, "description": "Any scheme-qualified identifiers for this boundary beyond its `@id`."},
    "sourceDataset": {"type": "string", "format": "iri", "description": "The `Dataset` this record was published as part of."}
  },
  "required": ["@id", "@type", "boundaryOf", "geometry", "validFrom"],
  "additionalProperties": true
}