The widget code is just a javascript library. Being a Javascript library displayed in the browser it is visible and is really nothing more than a wrapper around API calls. So I am not sure what level of detail you are looking for from a security perspective. It is like any other Javascript library out there. Anyone with a web browser can look at the code in the library. Unless you can narrow the question down whether or not this file can be used to hack Purecloud is way to broad of a question. The widget library is confined to a specific area of purecloud.
Second, I would strongly encourage you to take a look at our Web Messaging API. While we continue to support our WebChat API, Web Messaging is where all of the R & D efforts in the organization is being spent.
Thanks,
John Carnell
Manager, Developer Engagement