cordova -d plugin add https://github.com/phonegap/phonegap-facebook-plugin.git --variable APP_ID="123456789" --variable APP_NAME="myApplication"

npm ERR! addLocal Could not install /path_to_cloned/phonegap-facebook-plugin
Error: Failed to fetch plugin /path_to_cloned/phonegap-facebook-plugin via registry.

Probably this is either a connection problem, or plugin spec is incorrect.
Check your connection and plugin name/version/URL.
Error: ENOENT, open '/path_to_cloned/phonegap-facebook-plugin'
    at registry.fetch.fail.then.pinfo (/usr/local/lib/node_modules/cordova/node_modules/cordova-lib/src/plugman/fetch.js:146:33)
    at _rejected (/usr/local/lib/node_modules/cordova/node_modules/q/q.js:797:24)
    at /usr/local/lib/node_modules/cordova/node_modules/q/q.js:823:30
    at Promise.when (/usr/local/lib/node_modules/cordova/node_modules/q/q.js:1035:31)
    at Promise.promise.promiseDispatch (/usr/local/lib/node_modules/cordova/node_modules/q/q.js:741:41)
    at /usr/local/lib/node_modules/cordova/node_modules/q/q.js:557:44
    at flush (/usr/local/lib/node_modules/cordova/node_modules/q/q.js:108:17)
    at process._tickCallback (node.js:448:13)