This NPM action allows you to query npmjs.com for NPM packages. It then shows you a result-set of matching packages with their descriptions, allowing you to open any of them in your browser.
Clone/download this repository's master and double-click the NPM.lbaction. LaunchBar will then prompt you, whether you'd want to install it.
Type npm and NPM should then appear. Press the Space key and type in a package name (e.g. webp) - then simply wait a few seconds. Press the Enter key to open the chosen package in your browser (-> npmjs.com).