diff --git a/core/modules/book/src/BookStorageInterface.php b/core/modules/book/src/BookStorageInterface.php
index fa7ab85..0a42a92 100644
--- a/core/modules/book/src/BookStorageInterface.php
+++ b/core/modules/book/src/BookStorageInterface.php
@@ -52,7 +52,7 @@ public function getChildRelativeDepth($book_link, $max_depth);
    *   Deletes a book entry.
    *
    * @return mixed
-   *   The return value is dependent on the database connection.
+   *   Number of deleted book entires.
    */
   public function delete($nid);
 
@@ -73,19 +73,8 @@ public function loadBookChildren($pid);
    * @param int|string $bid
    *   The ID of the book that we are building the tree for.
    * @param array $parameters
-   *   An associative array of build parameters. Possible keys:
-   *   - expanded: An array of parent link ids to return only book links that
-   *     are children of one of the plids in this list. If empty, the whole
-   *     outline is built, unless 'only_active_trail' is TRUE.
-   *   - active_trail: An array of nids, representing the coordinates of the
-   *     currently active book link.
-   *   - only_active_trail: Whether to only return links that are in the active
-   *     trail. This option is ignored, if 'expanded' is non-empty.
-   *   - min_depth: The minimum depth of book links in the resulting tree.
-   *     Defaults to 1, which is the default to build a whole tree for a book.
-   *   - max_depth: The maximum depth of book links in the resulting tree.
-   *   - conditions: An associative array of custom database select query
-   *     condition key/value pairs; see _menu_build_tree() for the actual query.
+   *   An associative array of build parameters. For info about individual
+   *   parameters see BookManager::bookTreeBuild().
    * @param int $min_depth
    *   The minimum depth of book links in the resulting tree.
    * @param int $max_depth