{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "#/components/schemas/Annotation",
  "title": "Annotation",
  "description": "Text annotation (URL citation)",
  "properties": {
    "end_index": {
      "description": "End character index of the annotated text",
      "format": "int32",
      "type": "integer"
    },
    "start_index": {
      "description": "Start character index of the annotated text",
      "format": "int32",
      "type": "integer"
    },
    "title": {
      "description": "Title of the cited source",
      "type": "string"
    },
    "type": {
      "description": "Annotation type (url_citation)",
      "type": "string"
    },
    "url": {
      "description": "URL of the cited source",
      "type": "string"
    }
  },
  "type": "object"
}