Estoy realizando un ejemplo de la página web de instrucciones API de Google Calendar. Pongo el código en el archivo example.js y lo comienzo connodo ejemplo.js en línea de comando.

var fs = require('fs');
var readline = require('readline');
var google = require('googleapis');
var googleAuth = require('google-auth-library');

// If modifying these scopes, delete your previously saved credentials
// at ~/.credentials/calendar-nodejs-quickstart.json
var SCOPES = ['https://www.googleapis.com/auth/calendar'];
var TOKEN_DIR = (process.env.HOME || process.env.HOMEPATH ||
    process.env.USERPROFILE) + '/.credentials/';
var TOKEN_PATH = TOKEN_DIR + 'calendar-nodejs-quickstart.json';

// Load client secrets from a local file.
fs.readFile('client_secret.json', function processClientSecrets(err, content) {
  if (err) {
    console.log('Error loading client secret file: ' + err);
    return;
  }
  // Authorize a client with the loaded credentials, then call the
  // Google Calendar API.
  authorize(JSON.parse(content), listEvents);
});

/**
 * Create an OAuth2 client with the given credentials, and then execute the
 * given callback function.
 *
 * @param {Object} credentials The authorization client credentials.
 * @param {function} callback The callback to call with the authorized client.
 */
function authorize(credentials, callback) {
  var clientSecret = credentials.installed.client_secret;
  var clientId = credentials.installed.client_id;
  var redirectUrl = credentials.installed.redirect_uris[0];
  var auth = new googleAuth();
  var oauth2Client = new auth.OAuth2(clientId, clientSecret, redirectUrl);

  // Check if we have previously stored a token.
  fs.readFile(TOKEN_PATH, function(err, token) {
    if (err) {
      getNewToken(oauth2Client, callback);
    } else {
      oauth2Client.credentials = JSON.parse(token);
      callback(oauth2Client);
    }
  });
}

/**
 * Get and store new token after prompting for user authorization, and then
 * execute the given callback with the authorized OAuth2 client.
 *
 * @param {google.auth.OAuth2} oauth2Client The OAuth2 client to get token for.
 * @param {getEventsCallback} callback The callback to call with the authorized
 *     client.
 */
function getNewToken(oauth2Client, callback) {
  var authUrl = oauth2Client.generateAuthUrl({
    access_type: 'offline',
    scope: SCOPES
  });
  console.log('Authorize this app by visiting this url: ', authUrl);
  var rl = readline.createInterface({
    input: process.stdin,
    output: process.stdout
  });
  rl.question('Enter the code from that page here: ', function(code) {
    rl.close();
    oauth2Client.getToken(code, function(err, token) {
      if (err) {
        console.log('Error while trying to retrieve access token', err);
        return;
      }
      oauth2Client.credentials = token;
      storeToken(token);
      callback(oauth2Client);
    });
  });
}

/**
 * Store token to disk be used in later program executions.
 *
 * @param {Object} token The token to store to disk.
 */
function storeToken(token) {
  try **strong text**{
    fs.mkdirSync(TOKEN_DIR);
  } catch (err) {
    if (err.code != 'EEXIST') {
      throw err;
    }
  }
  fs.writeFile(TOKEN_PATH, JSON.stringify(token));
  console.log('Token stored to ' + TOKEN_PATH);
}

/**
 * Lists the next 10 events on the user's primary calendar.
 *
 * @param {google.auth.OAuth2} auth An authorized OAuth2 client.
 */
function listEvents(auth) {
  var calendar = google.calendar('v3');
  calendar.events.list({
    auth: auth,
    calendarId: 'primary',
    timeMin: (new Date()).toISOString(),
    maxResults: 10,
    singleEvents: true,
    orderBy: 'startTime'
  }, function(err, response) {
    if (err) {
      console.log('The API returned an error: ' + err);
      return;
    }
    var events = response.items;
    if (events.length == 0) {
      console.log('No upcoming events found.');
    } else {
      console.log('Upcoming 10 events:');
      for (var i = 0; i < events.length; i++) {
        var event = events[i];
        var start = event.start.dateTime || event.start.date;
        console.log('%s - %s', start, event.summary);
      }
    }
  });
}

todo funciona todo el tiempo. Pero cuando trato de insertar un evento en el calendario de Google con este código.

  authorize(JSON.parse(content), addEvent);

function addEvent(auth) {
    var event = {
      'summary': 'Google I/O 2015',
      'location': '800 Howard St., San Francisco, CA 94103',
      'description': 'A chance to hear more about Google\'s developer products.',
      'start': {
        'dateTime': '2015-05-28T09:00:00-07:00',
        'timeZone': 'America/Los_Angeles',
      },
      'end': {
        'dateTime': '2015-05-28T17:00:00-07:00',
        'timeZone': 'America/Los_Angeles',
      },
      'recurrence': [
        'RRULE:FREQ=DAILY;COUNT=2'
      ],
      'attendees': [
        {'email': '[email protected]'},
        {'email': '[email protected]'},
      ],
      'reminders': {
        'useDefault': false,
        'overrides': [
          {'method': 'email', 'minutes': 24 * 60},
          {'method': 'popup', 'minutes': 10},
        ],
      },
    };

var calendar = google.calendar('v3');
    calendar.events.insert({
      auth: auth,
      calendarId: 'primary',
      resource: event,
    }, function(err, event) {
      if (err) {
        console.log('There was an error contacting the Calendar service: ' + err);
        return;
      }
      console.log('Event created: %s', event.htmlLink);
    });

Invariablemente obtengo:

Se produjo un error al contactar con el servicio de calendario: Error: falta la hora de finalización.

Que estoy haciendo mal.