The Clash of Clans developer website is now live at https://developer.clashofclans.com. Access Clan Search, Global and Local Leaderboards, Clan and Player Profiles and Leagues. More to come soon!
The Clash Game API provides near real-time access to game related data. In order to access the API, you need a developer account and a key for your application. Getting Started page can be found here, and Supercell’s Terms of Service here.
Source: Supercell Forum