diff --git a/core/lib/Drupal/Core/Config/Entity/ConfigEntityInterface.php b/core/lib/Drupal/Core/Config/Entity/ConfigEntityInterface.php
index 5aa737d..9b33764 100644
--- a/core/lib/Drupal/Core/Config/Entity/ConfigEntityInterface.php
+++ b/core/lib/Drupal/Core/Config/Entity/ConfigEntityInterface.php
@@ -18,7 +18,7 @@
    * Returns the original ID.
    *
    * @return string|null
-   *   The original ID, if any.
+   *   The original ID or NULL.
    */
   public function getOriginalId();
 
@@ -28,23 +28,21 @@ public function getOriginalId();
    * @param string $id
    *   The new ID to set as original ID.
    *
-   * @return self
+   * @return $this
    */
   public function setOriginalId($id);
 
   /**
    * Enables the configuration entity.
    *
-   * @return \Drupal\Core\Config\Entity\ConfigEntityInterface
-   *   The configuration entity.
+   * @return $this
    */
   public function enable();
 
   /**
    * Disables the configuration entity.
    *
-   * @return \Drupal\Core\Config\Entity\ConfigEntityInterface
-   *   The configuration entity.
+   * @return $this
    */
   public function disable();
 
@@ -54,8 +52,7 @@ public function disable();
    * @param bool $status
    *   The status of the configuration entity.
    *
-   * @return \Drupal\Core\Config\Entity\ConfigEntityInterface
-   *   The class instance that this method is called on.
+   * @return $this
    */
   public function setStatus($status);
 
@@ -80,14 +77,25 @@ public function setSyncing($status);
    *     checking and managing the status.
    *
    * @return bool
+   *   Whether the entity is enabled or not.
    */
   public function status();
 
   /**
-   * Returns whether the configuration entity is created, updated or deleted
-   * through the import process.
+   * Returns if this entity is changed as part of an import process.
+   *
+   * Code that changes configuration based on new, changed or deleted
+   * configuration entities must check this flag and only be executed if it is
+   * FALSE.
+   *
+   * An example is the default body field that is created when a new content
+   * type is created. If that creation happens as part of a configuration sync,
+   * the default body field will either be explicitly created or has been
+   * removed.
    *
    * @return bool
+   *   TRUE if the configuration entity is created, updated or deleted through
+   *   the import process.
    */
   public function isSyncing();
 
@@ -98,7 +106,7 @@ public function isSyncing();
    *   The name of the property that should be returned.
    *
    * @return mixed
-   *   The property, if existing, NULL otherwise.
+   *   The property if it exists, or NULL otherwise.
    */
   public function get($property_name);
 
@@ -117,7 +125,7 @@ public function set($property_name, $value);
    *
    * These are the values that get saved into config.
    *
-   * @return array
+   * @return mixed[]
    *   An array of exportable properties and their values.
    */
   public function getExportProperties();
diff --git a/core/lib/Drupal/Core/Entity/EntityInterface.php b/core/lib/Drupal/Core/Entity/EntityInterface.php
index 3e6af82..26a1853 100644
--- a/core/lib/Drupal/Core/Entity/EntityInterface.php
+++ b/core/lib/Drupal/Core/Entity/EntityInterface.php
@@ -223,7 +223,7 @@ public function postSave(EntityStorageControllerInterface $storage_controller, $
    *
    * @param \Drupal\Core\Entity\EntityStorageControllerInterface $storage_controller
    *   The entity storage controller object.
-   * @param array $values
+   * @param mixed[] $values
    *   An array of values to set, keyed by property name. If the entity type has
    *   bundles the bundle key has to be specified.
    */
@@ -232,7 +232,7 @@ public static function preCreate(EntityStorageControllerInterface $storage_contr
   /**
    * Acts on an entity after it is created but before hooks are invoked.
    *
-   * @param EntityStorageControllerInterface $storage_controller
+   * @param \Drupal\Core\Entity\EntityStorageControllerInterface $storage_controller
    *   The entity storage controller object.
    */
   public function postCreate(EntityStorageControllerInterface $storage_controller);
@@ -244,7 +244,7 @@ public function postCreate(EntityStorageControllerInterface $storage_controller)
    *
    * @param EntityStorageControllerInterface $storage_controller
    *   The entity storage controller object.
-   * @param \Drupal\Core\Entity\EntityInterface[] $entities
+   * @param static[] $entities
    *   An array of entities.
    */
   public static function preDelete(EntityStorageControllerInterface $storage_controller, array $entities);
@@ -256,7 +256,7 @@ public static function preDelete(EntityStorageControllerInterface $storage_contr
    *
    * @param EntityStorageControllerInterface $storage_controller
    *   The entity storage controller object.
-   * @param \Drupal\Core\Entity\EntityInterface[] $entities
+   * @param static[] $entities
    *   An array of entities.
    */
   public static function postDelete(EntityStorageControllerInterface $storage_controller, array $entities);
@@ -266,7 +266,7 @@ public static function postDelete(EntityStorageControllerInterface $storage_cont
    *
    * @param EntityStorageControllerInterface $storage_controller
    *   The entity storage controller object.
-   * @param \Drupal\Core\Entity\EntityInterface[] $entities
+   * @param static[] $entities
    *   An array of entities.
    */
   public static function postLoad(EntityStorageControllerInterface $storage_controller, array &$entities);
@@ -284,7 +284,7 @@ public function createDuplicate();
    * Returns the entity type definition.
    *
    * @return \Drupal\Core\Entity\EntityTypeInterface
-   *   Entity type definition.
+   *   The entity type definition.
    */
   public function getEntityType();