Google this week began offering an alpha version of Google APIs Client Library for JavaScript, which provides access to HTTP-based APIs on the Web, as well as to many of Google’s public APIs.

Specifically, Googlebot cannot access your JavaScript and/or CSS files because of restrictions in your robots.txt file.

The update specifies that, for optimal rendering and indexing, you should allow Googlebot access to the JavaScript, CSS, and image files used by your page.