WebsAndLibraries.js

jQuery.ajax({
	url: "/_api/web/webs?$expand=Lists",
	headers: { accept: "application/json;odata=verbose"}
}).done(function(json){
	var i=0, j=0, html=[], web=null, list=null;
	html.push('<table><tr><th>Web</th><th>Library</th><th>Description</th></tr>')
	for (;i<json.d.results.length;i++){
		web = json.d.results[i];
		for (;j<web.Lists.results.length;j++){
			list = web.Lists.results[j];
			// filter for only visible, document libraries
			if (!list.Hidden && list.BaseType===1) {
				html.push('<tr><td>'+web.Title+'</td><td>'+list.Title+'</td><td>'+list.Description+'</td></tr>');
			}
		}
	}
	html.push('</table>');
	// place the generated table on the page somewhere in a div with the id of LibrarySummary
	jQuery("#LibrarySummary").html(html.join(''));
});