Try like below.
$('#calendar').fullCalendar({
events: [
{
title: 'My Event',
start: '2010-01-01',
description: 'This is a cool event'
}
],
eventRender: function(event, element) {
element.qtip({
content: event.description
});
}
});
For more info :
eventRender
I hope this will help to you.