diff --git a/plugin_type_example/src/Annotation/Sandwich.php b/plugin_type_example/src/Annotation/Sandwich.php
index ed1626c..1b8f5a9 100644
--- a/plugin_type_example/src/Annotation/Sandwich.php
+++ b/plugin_type_example/src/Annotation/Sandwich.php
@@ -19,6 +19,9 @@ use Drupal\Component\Annotation\Plugin;
  * @see \Drupal\plugin_type_example\SandwichPluginManager
  * @see plugin_api
  *
+ * Note that the "@ Annotation" line below is required and should be the last
+ * line in the docblock. It's used for discovery of Annotation definitions.
+ *
  * @Annotation
  */
 class Sandwich extends Plugin {
diff --git a/plugin_type_example/src/Controller/PluginTypeExampleController.php b/plugin_type_example/src/Controller/PluginTypeExampleController.php
index e2e8ee9..4463596 100644
--- a/plugin_type_example/src/Controller/PluginTypeExampleController.php
+++ b/plugin_type_example/src/Controller/PluginTypeExampleController.php
@@ -63,9 +63,9 @@ class PluginTypeExampleController extends ControllerBase {
       // are defined in the annotation at the top of the plugin class: see
       // \Drupal\plugin_type_example\Plugin\Sandwich\ExampleHamSandwich.
       $items[] = t("@id (calories: @calories, description: @description )", array(
-        '@id'       => $sandwich_plugin_definition['id'],
+        '@id' => $sandwich_plugin_definition['id'],
         '@calories' => $sandwich_plugin_definition['calories'],
-        '@description'   => $sandwich_plugin_definition['description'],
+        '@description' => $sandwich_plugin_definition['description'],
       ));
     }
 
diff --git a/plugin_type_example/src/SandwichInterface.php b/plugin_type_example/src/SandwichInterface.php
index 39a54a6..210f3d9 100644
--- a/plugin_type_example/src/SandwichInterface.php
+++ b/plugin_type_example/src/SandwichInterface.php
@@ -6,7 +6,7 @@
  *
  * When defining a new plugin type you need to define an interface that all
  * plugins of the new type will implement. This ensures that consumers of the
- * plugin type of a consistent way of accessing the plugins functionality. It
+ * plugin type have a consistent way of accessing the plugin's functionality. It
  * should include access to any public properties, and methods for accomplishing
  * whatever business logic anyone accessing the plugin might want to use.
  *
diff --git a/plugin_type_example/src/SandwichPluginManager.php b/plugin_type_example/src/SandwichPluginManager.php
index f137b43..e77fce5 100644
--- a/plugin_type_example/src/SandwichPluginManager.php
+++ b/plugin_type_example/src/SandwichPluginManager.php
@@ -37,7 +37,9 @@ class SandwichPluginManager extends DefaultPluginManager {
   public function __construct(\Traversable $namespaces, CacheBackendInterface $cache_backend, ModuleHandlerInterface $module_handler) {
     // We replace the $subdir parameter with our own value.
     // This tells the plugin manager to look for Sandwich plugins in the
-    // 'src/Plugin/Sandwich' subdirectory of any enabled modules.
+    // 'src/Plugin/Sandwich' subdirectory of any enabled modules. This also
+    // serves to define the PSR-4 subnamespace in which sandwich plugins will
+    // live. Example: Drupal\{module_name}\Plugin\Sandwich\MySandwichPlugin;
     $subdir = 'Plugin/Sandwich';
 
     // The name of the interface that plugins should adhere to. Drupal will