JavaScript License Web Labels is a format that the FSF proposes webmasters use to publish license information and source code for the JavaScript they deploy on their sites. It looks simple enough to be accessible to any visitor, but provides enough detail that automated tools can confirm that all of a site's JavaScript is actually free. Such software will make it practical for people to run free JavaScript and refuse nonfree code. Tools like this are already being developed: LibreJS is a plug-in for Mozilla-based browsers that will support JavaScript License Web Labels.