With this event I could set notes to user by department selected on chat start.
Example:
<script>

$zopim(function() {
$zopim.livechat.set({
language: 'pt_BR',
name: 'user',
email: 'user@site.com',
onChatStart: function(e) {
var departament = e.Departament;

$.ajax({
url: 'http://www.mysite.com/getNotesByUserByDepartament',
data: {User: 'xxxxxx', Departament: departament},
type: "POST",
dataType: "json",
success: function (returnNotes) {
$zopim.livechat.setNotes(returnNotes);
});
});
}
});
});

</script>