json_schema: {
      "$schema": "http://json-schema.org/draft-04/schema#",
      "title": "Contacts",
      "description": "Contacts: name, freeform contact methods",
      "type": "object",
      "properties": {
          "name": {
              "type": "string"
          }
      },
      "minProperties": 1,
      "maxProperties": 5,
      "required": [
          "name"
      ],
      "additionalProperties": {
          "type": "string",
          "pattern": "^([0-9]{3}) [0-9]{3}-[0-9]{4}$"
      }
  }