AngularJS: issues creating an API request

I have a scenario in which I have to deal with a misconfigured server, which only understands a stringified JSON. What works with the server is:

    var req = JSON.stringify({id: 0, method: 'getToken', params: ['something', 'password', 'some_more_randomness']});
    $http({
        url: 'http://something.com/API',
        method: 'POST',
        data: req,
        responseType: 'json'
    }).success(function (data) {
        console.log('data', data);
    }); // works

And I've tried to use $resources to take the hassle out of the picture, and I have something like:

var apiService = angular.module('apiService', ['ngResource']);

/**
* apiService Module
*
*/

apiService.factory('API', ['$resource', function ($resource) {
    return $resource('http://somethng.com/API', {}, {
        getToken: {
            method: 'POST',
            params: JSON.stringify({id: 0, method: 'getToken', params: ['something', 'password', 'some_more_randomness']})
        }
    });
}]);

Which doesn't work. The server cannot parse the parameters. I'm afraid I don't have access to the server to allow posting properly to it.

What I'd like to do, is to make the exact request from within the service. Other variations – enclosing JSON.stringify inside [] doesn't help either.

What can be done here?