{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://civitasconnect.digital/core/extensions/v1",
  "title": "CORE JSON Schema Extensions",
  "description": "Defines the x-* extension fields used by CORE JSON Schema documents and CORE editor metadata.",
  "type": "object",
  "properties": {
    "x-core-ref": {
      "$ref": "#/$defs/CoreRef"
    },
    "x-xsd-source": {
      "$ref": "#/$defs/XsdSource"
    },
    "x-ui-position": {
      "$ref": "#/$defs/UiPosition"
    },
    "x-ui-styles": {
      "$ref": "#/$defs/UiStyles"
    }
  },
  "additionalProperties": false,
  "$defs": {
    "CoreRef": {
      "description": "Foreign-key reference metadata: the annotated string field holds the CORE URN of another artifact. 'type' names the referenced artifact and may be either a concrete artifact URN (e.g. an Element URN — a strongly-typed FK whose existence is checked against the registry) or an 'urn:core:type:<Kind>' category URN (used by the generic CORE-IR artifact meta-schemas, where the concrete target is not fixed). The URN is always global.",
      "type": "object",
      "required": ["type"],
      "properties": {
        "type": {
          "type": "string",
          "description": "CORE URN of the referenced artifact (a concrete artifact URN) or an 'urn:core:type:<Kind>' category URN.",
          "pattern": "^urn:core:"
        }
      },
      "additionalProperties": false
    },
    "XsdSource": {
      "description": "URN of the raw XSD artifact from which a JSON Schema view was derived.",
      "type": "string",
      "pattern": "^urn:"
    },
    "UiPosition": {
      "description": "Visual position in the pipeline canvas (x/y coordinates in pixels).",
      "type": "object",
      "properties": {
        "x": { "type": "number" },
        "y": { "type": "number" }
      }
    },
    "UiStyles": {
      "description": "Host UI state carried by a stored model — the editor diagram (nodes, edges, positions, labels). Opaque to the registry (host-owned, split off on read); shape is intentionally permissive.",
      "type": "object"
    }
  }
}