Tool Labs (or Tools) is a hosting environment for community developers working on tools and bots that help users maintain and use Wikimedia wikis. Tool Labs provides access to replicas of Wikimedia databases and other services that allow developers to easily compute analytics, do bot work, and create tools to help editors and other volunteers in their work. The infrastructure is supported by a dedicated group of Wikimedia Foundation staff and volunteers.
Read more about Tool Labs on wikitech (the Wikimedia technical infrastructure wiki).