These are the readme of the Validator extension.

Extension page on mediawiki.org: https://www.mediawiki.org/wiki/Extension:Validator
Latest version of the release notes: https://gerrit.wikimedia.org/r/gitweb?p=mediawiki/extensions/Validator.git;a=blob;f=README

== About ==

Validator is an extension that makes parameter validation functionality available
to other extensions. This enables other extensions to validate parameters, set them
to their defaults, and generate error messages, while only defining the parameters
and their criteria.

Notes on installing Validator are found in the file INSTALL.

== Contributors ==

https://www.mediawiki.org/wiki/Extension:Validator#Contributing_to_the_project
