Docs: Various docblock improvements.

See #51800


git-svn-id: https://develop.svn.wordpress.org/trunk@49790 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/post.php

@@ -5508,7 +5508,9 @@ function get_page_uri( $page = 0 ) {
  *     @type string|array $post_status  A comma-separated list or array of post statuses to include.
  *                                      Default 'publish'.
  * }
- * @return array|false Array of pages matching defaults or `$args`.
+ * @return WP_Post[]|int[]|false Array of pages (or hierarchical post type items). Boolean false if the
+ *                               specified post type is not hierarchical or the specified status is not
+ *                               supported by the post type.
  */
 function get_pages( $args = array() ) {
 	global $wpdb;