diff --git a/core/lib/Drupal/Core/Entity/Query/QueryInterface.php b/core/lib/Drupal/Core/Entity/Query/QueryInterface.php
index 8852f0b..7d6ad79 100644
--- a/core/lib/Drupal/Core/Entity/Query/QueryInterface.php
+++ b/core/lib/Drupal/Core/Entity/Query/QueryInterface.php
@@ -18,6 +18,7 @@
    * Gets the ID of the entity type for this query.
    *
    * @return string
+   *   The entity type ID.
    */
   public function getEntityTypeId();
 
@@ -73,7 +74,7 @@ public function getEntityTypeId();
    *   The value for $field. In most cases, this is a scalar and it's treated as
    *   case-insensitive. For more complex operators, it is an array. The meaning
    *   of each element in the array is dependent on $operator.
-   * @param $operator
+   * @param string|null $operator
    *   Possible values:
    *   - '=', '<>', '>', '>=', '<', '<=', 'STARTS_WITH', 'CONTAINS',
    *     'ENDS_WITH': These operators expect $value to be a literal of the
@@ -82,7 +83,7 @@ public function getEntityTypeId();
    *     literals of the same type as the column.
    *   - 'BETWEEN': This operator expects $value to be an array of two literals
    *     of the same type as the column.
-   * @param $langcode
+   * @param string|null $langcode
    *   Language code (optional). If omitted, any translation satisfies the
    *   condition. However, if two or more conditions omit the langcode within
    *   one condition group then they are presumed to apply to the same
@@ -90,7 +91,8 @@ public function getEntityTypeId();
    *   and another does not they are not presumed to apply to the same
    *   translation.
    *
-   * @return \Drupal\Core\Entity\Query\QueryInterface
+   * @return $this
+   *
    * @see \Drupal\Core\Entity\Query\andConditionGroup
    * @see \Drupal\Core\Entity\Query\orConditionGroup
    */
@@ -99,22 +101,24 @@ public function condition($field, $value = NULL, $operator = NULL, $langcode = N
   /**
    * Queries for a non-empty value on a field.
    *
-   * @param $field
+   * @param string $field
    *   Name of a field.
-   * @param $langcode
+   * @param string|null $langcode
    *   Language code (optional).
-   * @return \Drupal\Core\Entity\Query\QueryInterface
+   *
+   * @return $this
    */
   public function exists($field, $langcode = NULL);
 
   /**
    * Queries for an empty field.
    *
-   * @param $field.
+   * @param string $field.
    *   Name of a field.
-   * @param $langcode
+   * @param string|null $langcode
    *   Language code (optional).
-   * @return \Drupal\Core\Entity\Query\QueryInterface
+   *
+   * @return $this
    */
   public function notExists($field, $langcode = NULL);
 
@@ -128,27 +132,37 @@ public function notExists($field, $langcode = NULL);
    *   An optional integer to distinguish between multiple pagers on one page.
    *   If not provided, one is automatically calculated.
    *
-   * @return \Drupal\Core\Entity\Query\QueryInterface
-   *   The called object.
+   * @return $this
    */
   public function pager($limit = 10, $element = NULL);
 
   /**
-   * @param null $start
-   * @param null $length
-   * @return \Drupal\Core\Entity\Query\QueryInterface
-   *   The called object.
+   * Defines the range of the query.
+   *
+   * @param int|null $start
+   *   The first record from the result set to return. If NULL, removes any
+   *   range directives that are set.
+   * @param int|null $length
+   *   The maximum number of rows to return. If $start and $length are NULL,
+   *   then a complete result set will be generated. If $start is not NULL and
+   *   $length is NULL, then an empty result set will be generated.
+   *
+   * @return $this
    */
   public function range($start = NULL, $length = NULL);
 
   /**
-   * @param $field
-   *   Name of a field.
+   * Sorts the result set by a given field.
+   *
+   * @param string $field
+   *   Name of a field on which to sort.
    * @param string $direction
-   * @param $langcode
+   *   The direction to sort. Legal values are "ASC" and "DESC".
+   *   Any other value will be converted to "ASC".
+   * @param string|null $langcode
    *   Language code (optional).
-   * @return \Drupal\Core\Entity\Query\QueryInterface
-   *   The called object.
+   *
+   * @return $this
    */
   public function sort($field, $direction = 'ASC', $langcode = NULL);
 
@@ -157,8 +171,7 @@ public function sort($field, $direction = 'ASC', $langcode = NULL);
    *
    * For count queries, execute() returns the number entities found.
    *
-   * @return \Drupal\Core\Entity\Query\QueryInterface
-   *   The called object.
+   * @return $this
    */
   public function count();
 
@@ -171,14 +184,17 @@ public function count();
    *   specify what to sort on. This can be an entity or a field as described
    *   in condition().
    *
-   * @return \Drupal\Core\Entity\Query\QueryInterface
-   *   The called object.
+   * @return $this
    */
   public function tableSort(&$headers);
 
   /**
-   * @return \Drupal\Core\Entity\Query\QueryInterface
-   *   The called object.
+   * Enables or disables access checking for this query.
+   *
+   * @param bool $access_check
+   *   Whether access check is requested or not. Defaults to TRUE.
+   *
+   * @return $this
    */
   public function accessCheck($access_check = TRUE);
 
@@ -212,8 +228,9 @@ public function execute();
    * @endcode
    *
    * @return \Drupal\Core\Entity\Query\ConditionInterface
+   *   A condition object whose conditions will be combined with AND.
    */
-  public function andConditionGroup();
+    public function andConditionGroup();
 
   /**
    * Creates a new group of conditions ORed together.
@@ -240,6 +257,7 @@ public function andConditionGroup();
    * @endcode
    *
    * @return \Drupal\Core\Entity\Query\ConditionInterface
+   *   A condition object whose conditions will be combined with OR.
    */
   public function orConditionGroup();