json_schema: {
      "additionalProperties": false,
      "description": "An exception GTM server-side event.",
      "properties": {
          "description": {
              "description": "The description of the exception that occurred.",
              "maxLength": 4096,
              "type": [
                  "string",
                  "null"
              ]
          },
          "fatal": {
              "description": "Whether or not the exception was a fatal one.",
              "type": [
                  "boolean",
                  "null"
              ]
          }
      },
      "self": {
          "format": "jsonschema",
          "name": "exception",
          "vendor": "com.google.tag-manager.server-side",
          "version": "1-0-0"
      },
      "type": "object"
  }