diff --git a/classes/Config.php b/classes/Config.php
index 7d33665..69cb26b 100644
--- a/classes/Config.php
+++ b/classes/Config.php
@@ -65,10 +65,16 @@ class Config
      */
     public $curl_params = array();
 
-    private $configFile;
+    /**
+     * YAML config file path
+     * @var string
+     */
+    private $file;
 
     /**
      * Config constructor
+     *
+     * @param string $yamlfile YAML config file path
      */
     private function __construct($yamlfile)
     {
@@ -91,6 +97,8 @@ class Config
     /**
      * Get singleton instance
      *
+     * @param string $yamlfile YAML config file name
+     *
      * @return Config
      */
     public static function getInstance($yamlfile = 'config.yml')
diff --git a/tests/ConfigTest.php b/tests/ConfigTest.php
index 8ea8e84..6527ec3 100644
--- a/tests/ConfigTest.php
+++ b/tests/ConfigTest.php
@@ -12,8 +12,15 @@ use Alltube\Config;
 class ConfigTest extends \PHPUnit_Framework_TestCase
 {
 
+    /**
+     * Config class instance
+     * @var Config
+     */
     private $config;
 
+    /**
+     * Prepare tests
+     */
     protected function setUp()
     {
         $this->config = Config::getInstance('config_test.yml');
@@ -35,6 +42,10 @@ class ConfigTest extends \PHPUnit_Framework_TestCase
         $this->assertInternalType('string', $this->config->rtmpdump);
     }
 
+    /**
+     * Test the getInstance function with the CONVERT environment variable
+     * @return void
+     */
     public function testGetInstanceWithEnv()
     {
         putenv('CONVERT=1');