diff --git a/core/lib/Drupal/Component/Reflection/MockFileFinder.php b/core/lib/Drupal/Component/Reflection/MockFileFinder.php
index c6f26b4..140d190 100644
--- a/core/lib/Drupal/Component/Reflection/MockFileFinder.php
+++ b/core/lib/Drupal/Component/Reflection/MockFileFinder.php
@@ -1,7 +1,8 @@
 <?php
 
 /**
- * Definition of Drupal\Core\Plugin\Discovery\DumbFindFile.
+ * @file
+ * Definition of Drupal\Component\Reflection\MockFileFinder.
  */
 
 namespace Drupal\Component\Reflection;
@@ -9,9 +10,9 @@ namespace Drupal\Component\Reflection;
 use Doctrine\Common\Reflection\ClassFinderInterface;
 
 /**
- * A dumb file finder. It only returns a single filename.
+ * Defines a mock file finder that only returns a single filename.
  *
- * It can be used with \Doctrine\Common\Reflection\StaticReflectionParser if
+ * This can be used with \Doctrine\Common\Reflection\StaticReflectionParser if
  * the filename is known and inheritance is not a concern (for example, if
  * only the class annotation is needed).
  */
@@ -31,14 +32,14 @@ class MockFileFinder implements ClassFinderInterface {
   }
 
   /**
-   * Implements Doctrine\Common\Reflection\ClassFinderInterface::findFile().
+   * Implements \Doctrine\Common\Reflection\ClassFinderInterface::findFile().
    */
   public function findFile($class) {
     return $this->filename;
   }
 
   /**
-   * Factory for the mock file finder.
+   * Creates new mock file finder objects.
    */
   static public function create($filename) {
     $object = new static(array());
diff --git a/core/lib/Drupal/Core/Annotation/Plugin.php b/core/lib/Drupal/Core/Annotation/Plugin.php
index ee5977f..7018b77 100644
--- a/core/lib/Drupal/Core/Annotation/Plugin.php
+++ b/core/lib/Drupal/Core/Annotation/Plugin.php
@@ -10,6 +10,11 @@ namespace Drupal\Core\Annotation;
 use Drupal\Core\Annotation\AnnotationInterface;
 
 /**
+ * Defines a Plugin object.
+ *
+ * @todo
+ *   Add some documentation about what plugins are...
+ *
  * @Annotation
  */
 class Plugin implements AnnotationInterface {
@@ -44,4 +49,5 @@ class Plugin implements AnnotationInterface {
   public function get() {
     return $this->definition;
   }
+
 }
diff --git a/core/lib/Drupal/Core/Annotation/Translation.php b/core/lib/Drupal/Core/Annotation/Translation.php
index ebe886d..4ba68d2 100644
--- a/core/lib/Drupal/Core/Annotation/Translation.php
+++ b/core/lib/Drupal/Core/Annotation/Translation.php
@@ -10,6 +10,11 @@ namespace Drupal\Core\Annotation;
 use Drupal\Core\Annotation\AnnotationInterface;
 
 /**
+ * Defines a translation object.
+ *
+ * @todo
+ *   Document this class.
+ *
  * @Annotation
  */
 class Translation implements AnnotationInterface {
@@ -44,4 +49,5 @@ class Translation implements AnnotationInterface {
   public function get() {
     return $this->translation;
   }
+
 }
diff --git a/core/lib/Drupal/Core/Plugin/Discovery/AnnotatedClassDiscovery.php b/core/lib/Drupal/Core/Plugin/Discovery/AnnotatedClassDiscovery.php
index 1ef5c46..658be56 100644
--- a/core/lib/Drupal/Core/Plugin/Discovery/AnnotatedClassDiscovery.php
+++ b/core/lib/Drupal/Core/Plugin/Discovery/AnnotatedClassDiscovery.php
@@ -16,7 +16,7 @@ use Doctrine\Common\Annotations\AnnotationRegistry;
 use Doctrine\Common\Reflection\StaticReflectionParser;
 
 /**
- * A discovery mechanism that finds annotated plugins in PSR-0 namespaces.
+ * Defines a discovery mechanism to find annotated plugins in PSR-0 namespaces.
  */
 class AnnotatedClassDiscovery implements DiscoveryInterface {
 
@@ -38,6 +38,10 @@ class AnnotatedClassDiscovery implements DiscoveryInterface {
 
   /**
    * Implements Drupal\Component\Plugin\Discovery\DiscoveryInterface::getDefinitions().
+   *
+   * @todo
+   *   Inline documentation and whitespace should be added to this method to
+   *   make it more legible.
    */
   public function getDefinitions() {
     $definitions = array();
diff --git a/core/modules/aggregator/lib/Drupal/aggregator/Plugin/aggregator/fetcher/DefaultFetcher.php b/core/modules/aggregator/lib/Drupal/aggregator/Plugin/aggregator/fetcher/DefaultFetcher.php
index 583b0be..bbe883c 100644
--- a/core/modules/aggregator/lib/Drupal/aggregator/Plugin/aggregator/fetcher/DefaultFetcher.php
+++ b/core/modules/aggregator/lib/Drupal/aggregator/Plugin/aggregator/fetcher/DefaultFetcher.php
@@ -15,9 +15,7 @@ use Drupal\Core\Annotation\Translation;
  * Defines a default fetcher implementation.
  *
  * Uses drupal_http_request() to download the feed.
- */
-
-/**
+ *
  * @Plugin(
  *   id = "aggregator",
  *   title = @Translation("Default fetcher"),