I would like to be able to access the url parameters in my run function and make actions based on those params. However, I was pretty surprised to see that ui.router's $stateParams object is empty in my run function. 
angular.module('app', ['ui.router'])
.run(['$rootScope', '$state', '$stateParams', '$location', function($rootScope, $state, $stateParams, $location) {
    $rootScope.$state = $state;
    $rootScope.location = $location;
    $rootScope.$stateParams = $stateParams;
    $rootScope.$on('$stateChangeStart', function(event, toState) {
      if (toState.name === 'main') {
      event.preventDefault();
      $state.go('main.child', {
        param: 1
      })
      }
    });
    console.log('$stateParams is empty!');
    console.log($stateParams);
    console.log($rootScope.$stateParams);
}])
.config(['$stateProvider', '$urlRouterProvider', '$locationProvider', function($stateProvider, $urlRouterProvider, $locationProvider) {
    $stateProvider
        .state('main', {
            url: '',
            template: '<div>hey</div><div ui-view></div>'
        })
        .state('main.child', {
            url: '/:param',
            template: 'child state template'
        });
}]);
Is it possible to access the params accessed from $stateParams in the run function? Or are they only available in the config function? Why are they not accessible in the run function? 
Plnkr: http://plnkr.co/edit/1YXKRmR48LyxbGXWq66Y?p=preview
Thanks for any help.