// main.js
(function () {
//Creates the anonymous user agent so that you can send messages
var userAgent = new SIP.UA();
// send the message when the button is clicked
document.getElementById('send').addEventListener("click", function() {
userAgent.message("[email protected]", "Hello Bryan!");}, false);
}) ();
<!DOCTYPE html>
<html>
<body>
<button id="send">Send Message</button>
<script src="sip-devel.min.js"></script>
<script src="main.js"></script>
</body>
</html>