Webmaster tools are used to submit your website to the search engines and you can get a different SEO analysis report by the webmaster tool and on behalf of that report you can improve your site in which area you find your pages are not enough capability to get a good ranking in the search engines.
There are a list of mainly used webmaster tools:
Google Search console
Google webmaster tool is a search engine tool used to submit your website to increase the visibility in Google searches. The tool also helps to find backlinks, submit sitemap and analyze various data to improve optimization techniques for your website.