I want to know how many stackexchange sites there are. Querying http://api.stackexchange.com/2.2/sites , using a filter that makes "total" appear, I find that the value returned for total is always zero. For example,

http://api.stackexchange.com/2.2/sites?filter=!6P-i5S514Gfnl

Responds:

{ "total": 0 }

Is that the intended behavior?