Rest API filter

Hello,

I am making a request to the Contacts module. Sugar only has two contacts in the system. One contains the word Smith for the Contact name. The filter does not seem to apply as all the records are returned - two in this case. Is there something that needs to be setup on the sugar side?

http://FQDN/sugarcrm/rest/v11_4/Contacts/filter 

POST:

{ "filter":[ { "name":{ "$contains":"Smith" } } ] }