Manual:Noindex
From Linux Web Expert
Noindex can be used to prevent indexing of a page by search engines.
Using Wikitext
To change the index preferences for specific pages, use one of these magic words:
__INDEX____NOINDEX__
These magic words work for a given namespace. One may need to adjust $wgExemptFromUserRobotsControl.
To test whether they function for a given page, you can use the PHP function Title::canUseNoindex().
Using site Configuration
There are some site configurations that can be set. Some of them:
Using PHP
An example code in PHP, for example to be used by extension developers, would be:
$wgOut->setRobotPolicy('noindex,nofollow');
Or, if one wished to be more selective:
$wgOut->setIndexPolicy('noindex');
