Tooltip for fullcalendar in year view

eventMouseover: function(calEvent, jsEvent) {
    var tooltip = '<div class="tooltipevent" style="width:100px;height:100px;background:#ccc;position:absolute;z-index:10001;">' + calEvent.title + '</div>';
    var $tooltip = $(tooltip).appendTo('body');

    $(this).mouseover(function(e) {
        $(this).css('z-index', 10000);
        $tooltip.fadeIn('500');
        $tooltip.fadeTo('10', 1.9);
    }).mousemove(function(e) {
        $tooltip.css('top', e.pageY + 10);
        $tooltip.css('left', e.pageX + 20);
    });
},

eventMouseout: function(calEvent, jsEvent) {
    $(this).css('z-index', 8);
    $('.tooltipevent').remove();
},

You can use the html title attribute without any tooltip lib :

$('#calendar').fullCalendar({
    events: [
        {
            title: 'My Event',
            start: '2014-01-01',
            tooltip: 'This is a cool event'
        }
        // more events here
    ],
    eventRender: function(event, element) {
        element.attr('title', event.tooltip);
    }
});