During this process, they’ve run into several frequent problems that may “negatively impact” your pages from ranking in the search results. Google has listed out some of those problems, so one would assume the new tool that Google is working on would highlight these issues to webmasters.
These are the highlighted issues:
If your web server is unable to handle the volume of crawl requests for resources, it may have a negative impact on our capability to render your pages. If you’d like to ensure that your pages can be rendered by Google, make sure your servers are able to handle crawl requests for resources.
Google says the new tool is coming to Google Webmaster Tools “in the coming days.”