diff --git a/src/Symfony/Component/DependencyInjection/ContainerBuilder.php b/src/Symfony/Component/DependencyInjection/ContainerBuilder.php
index 3d1fa8b7ba..262defd376 100644
--- a/src/Symfony/Component/DependencyInjection/ContainerBuilder.php
+++ b/src/Symfony/Component/DependencyInjection/ContainerBuilder.php
@@ -729,8 +729,8 @@ class ContainerBuilder extends Container implements TaggedContainerInterface
      * This methods allows for simple registration of service definition
      * with a fluid interface.
      *
-     * @param string $id    The service identifier
-     * @param string $class The service class
+     * @param string $id         The service identifier
+     * @param string $class|null The service class
      *
      * @return Definition A Definition instance
      */
diff --git a/src/Symfony/Component/DependencyInjection/Definition.php b/src/Symfony/Component/DependencyInjection/Definition.php
index 7781220a97..8eb90c9c86 100644
--- a/src/Symfony/Component/DependencyInjection/Definition.php
+++ b/src/Symfony/Component/DependencyInjection/Definition.php
@@ -265,6 +265,13 @@ class Definition
         return $this;
     }
 
+    /**
+     * Sets the properties to define when creating the service.
+     *
+     * @param array $properties
+     *
+     * @return $this
+     */
     public function setProperties(array $properties)
     {
         $this->properties = $properties;
@@ -272,11 +279,24 @@ class Definition
         return $this;
     }
 
+    /**
+     * Gets the properties to define when creating the service.
+     *
+     * @return array
+     */
     public function getProperties()
     {
         return $this->properties;
     }
 
+    /**
+     * Sets a specific property.
+     *
+     * @param string $name
+     * @param mixed  $value
+     *
+     * @return $this
+     */
     public function setProperty($name, $value)
     {
         $this->properties[$name] = $value;
@@ -299,7 +319,7 @@ class Definition
     }
 
     /**
-     * Sets a specific argument.
+     * Replaces a specific argument.
      *
      * @param int   $index
      * @param mixed $argument
@@ -854,7 +874,7 @@ class Definition
     }
 
     /**
-     * Sets autowired.
+     * Enables/disables autowiring.
      *
      * @param bool $autowired
      *