diff --git a/Mediator/Mediator.php b/Mediator/Mediator.php
index 7de6669..9a9c3f1 100644
--- a/Mediator/Mediator.php
+++ b/Mediator/Mediator.php
@@ -25,6 +25,11 @@ class Mediator implements MediatorInterface
     protected $database;
     protected $client;
 
+    /**
+     * @param Subsystem\Database $db
+     * @param Subsystem\Client   $cl
+     * @param Subsystem\Server   $srv
+     */
     public function setColleague(Subsystem\Database $db, Subsystem\Client $cl, Subsystem\Server $srv)
     {
         $this->database = $db;
@@ -32,19 +37,31 @@ class Mediator implements MediatorInterface
         $this->client = $cl;
     }
 
+    /**
+     * make request
+     */
     public function makeRequest()
     {
         $this->server->process();
     }
 
+    /**
+     * query db
+     *
+     * @return mixed
+     */
     public function queryDb()
     {
         return $this->database->getData();
     }
 
+    /**
+     * send response
+     *
+     * @param string $content
+     */
     public function sendResponse($content)
     {
         $this->client->output($content);
     }
-
-}
\ No newline at end of file
+}
diff --git a/Mediator/MediatorInterface.php b/Mediator/MediatorInterface.php
index 15ea67b..d7e6a41 100644
--- a/Mediator/MediatorInterface.php
+++ b/Mediator/MediatorInterface.php
@@ -13,15 +13,15 @@ interface MediatorInterface
      *
      * @param string $content
      */
-    function sendResponse($content);
+    public function sendResponse($content);
 
     /**
      * makes a request
      */
-    function makeRequest();
+    public function makeRequest();
 
     /**
      * queries the DB
      */
-    function queryDb();
+    public function queryDb();
 }
diff --git a/Mediator/Subsystem/Client.php b/Mediator/Subsystem/Client.php
index 899575d..ef00aa0 100644
--- a/Mediator/Subsystem/Client.php
+++ b/Mediator/Subsystem/Client.php
@@ -9,15 +9,21 @@ use DesignPatterns\Mediator\Colleague;
  */
 class Client extends Colleague
 {
-
+    /**
+     * request
+     */
     public function request()
     {
         $this->getMediator()->makeRequest();
     }
 
+    /**
+     * output content
+     *
+     * @param string $content
+     */
     public function output($content)
     {
         echo $content;
     }
-
 }
diff --git a/Mediator/Subsystem/Database.php b/Mediator/Subsystem/Database.php
index 92c4f17..80acf28 100644
--- a/Mediator/Subsystem/Database.php
+++ b/Mediator/Subsystem/Database.php
@@ -9,10 +9,11 @@ use DesignPatterns\Mediator\Colleague;
  */
 class Database extends Colleague
 {
-
+    /**
+     * @return string
+     */
     public function getData()
     {
         return "World";
     }
-
 }
diff --git a/Mediator/Subsystem/Server.php b/Mediator/Subsystem/Server.php
index f23414f..34b7400 100644
--- a/Mediator/Subsystem/Server.php
+++ b/Mediator/Subsystem/Server.php
@@ -9,7 +9,9 @@ use DesignPatterns\Mediator\Colleague;
  */
 class Server extends Colleague
 {
-
+    /**
+     * process on server
+     */
     public function process()
     {
         $data = $this->getMediator()->queryDb();