Parse.serverURL = 'http://MY_IP.compute-1.amazonaws.com/parse/';

Parse.Cloud.define("countUsers", function(request, response) {
    var query = new Parse.Query("_Users");
    query.count({
        success: function(count) {
            response.success(count);
        },
        error: function(error) {
            response.error("Count failed" + error.message);
        }
    });
});

Parse.Cloud.define('hello', function(request, response) {
  response.success('Hi'); // it works
});

Parse.Cloud.job('test', function(request, response){
     response.success('OK');
 });

{
    "code": 141,
    "error": "Invalid function: "hello""
}