The three meta tags the plugin adds to your home page are;

<meta name="google-site-verification" content="******" />
<meta name="msvalidate.01" content="******" />
<meta name="y_key" content="******" />

Naturally you get to specify the content values. You get those from the webmaster area of each search engine;

Google: http://mail.google.com/webmasters/
Bing: http://www.bing.com/webmaster
Yahoo: https://siteexplorer.search.yahoo.com/

When you activate the plugin, under your blog Settings menu you'll see an extra menu item called  PC Search Engine Verify. Click on that for the plugin options page where you can enter the information you've got from the webmaster tools for your domain.

Once you provide a content value for a specific search engine, the meta tag will be displayed in the head section of your home page. If there's no content value, the meta tag for that search engine isn't displayed.

The plugin has been added to the official wordpress plugin repository, which is where you should download it from to make sure you get any updates ..etc. You can get it from here;

http://wordpress.org/extend/plugins/pc-searchengine-verify/

Let me know how it works for you…

What the plugin does

You probably know that when a search engine spider visits your site, one of the first things it does is look for a file called robots.txt which tells it which files and folders it can go and look at. By default, WordPress lets every robot go everywhere. That might be ok for some people, but I prefer to exercise a bit more control over things.

For example, if the robot identifies itself as a bad bot – yes, some of them do – then I don't want it to go anywhere. All it's probably going to do is trawl for email addresses to add to a spam list somewhere. And I don't really want any robots poking their noses into such places as the WordPress admin folder. Control freak? Me? Don't know what you mean…

The solution is to add the names of bad bots to your robots.txt file and disallow them from going anywhere, and add the names of common search engine spiders and specify which locations or files they are allowed to visit.

This plugin will do that in a completely hands free way by setting up a virtual robots.txt file for your blog as soon as it's activated. Whenever a request for a robots.txt file comes in, WordPress will display the contents of your virtual robots.txt file. No physical file is created on your site but one is shown to the search engine bot.

By default, your virtual robots.txt file will have Google's Mediabot allowed, a bunch of spam-bots disallowed, and a few of the standard WordPress folders and files disallowed. The default collection of bad bots is borrowed from http://www.clickability.co.uk/robotstxt.html.

Ok, even though it's completely automated and hands free I admit there are times when I want to tweak what's contained in the virtual robots.txt file. There's now a handy options page which lets you edit the contents.

Oh yeah, and if you mess up your robots.txt file you can just deactivate and reactivate the plugin and it will revert back to the default list of rules.

Also, if the plugin detects an existing sitemap.xml file (or if you are using my XML Sitemap plugin) it will add a reference to your sitemap.xml to the end of the robots.txt file. I'm told this helps with the discovery of your sitemap.xml and indexing of your pages. That's got to be a good idea.

How to use the plugin

With the plugin now being hosted on WordPress, the easiest way to install this baby is to visit your blog admin pages, click the Plugins menu, and then click the Add New menu. In the search box type something like "robots.txt" and with a bit of luck you should see PC Robots.txt in the list that appears. To the right of it you'll see a link to Install the plugin. Click that.

If you happen to be using the version that was hosted on this site, please delete it and install a new version using the instruction above. That way you'll always have the latest version and you'll get notified of updates and such by WordPress.

The official download page is at http://wordpress.org/extend/plugins/pc-robotstxt/

And please do give me a shout to let me know if it works for you or not :-)