After long delay, we release a beta version of API
For now the calls will be unlimited. When oficial version will be released the free version will allow to make calls every 5 minutes.

The API returns the coins that works with no problem and are online.
example
{"name":"Dogecoin","tag":"DOGE","algo":"scrypt","reward":"250001.000000","prof":"7788.01","
lastprice":"0.00000122","avgday":"9146.18","avgweek":"7397.03","avgtwoweeks":"7136.88","avgmonth":"5339.77"}

hope it helps