diff --git a/src/wp-includes/post-functions.php b/src/wp-includes/post-functions.php
index 9897c81494..1b6af735e5 100644
--- a/src/wp-includes/post-functions.php
+++ b/src/wp-includes/post-functions.php
@@ -3608,10 +3608,10 @@ function _truncate_post_slug( $slug, $length = 200 ) {
  *
  * @since 2.3.0
  *
- * @param int    $post_id Optional. The Post ID. Does not default to the ID of the global $post.
- *                        Default 0.
- * @param string $tags    Optional. The tags to set for the post, separated by commas. Default empty.
- * @return array|false|WP_Error Will return false if $post_id is not an integer or is 0.
+ * @param int          $post_id Optional. The Post ID. Does not default to the ID of the global $post.
+ * @param string|array $tags    Optional. An array of tags to set for the post, or a string of tags
+ *                              separated by commas. Default empty.
+ * @return array|false|WP_Error Array of affected term IDs. WP_Error or false on failure.
  */
 function wp_add_post_tags( $post_id = 0, $tags = '' ) {
 	return wp_set_post_tags($post_id, $tags, true);
@@ -3624,11 +3624,11 @@ function wp_add_post_tags( $post_id = 0, $tags = '' ) {
  *
  * @see wp_set_object_terms()
  *
- * @param int    $post_id Optional. The Post ID. Does not default to the ID of the global $post.
- * @param string $tags    Optional. The tags to set for the post, separated by commas.
- *                        Default empty.
- * @param bool   $append  Optional. If true, don't delete existing tags, just add on. If false,
- *                        replace the tags with the new tags. Default false.
+ * @param int          $post_id Optional. The Post ID. Does not default to the ID of the global $post.
+ * @param string|array $tags    Optional. An array of tags to set for the post, or a string of tags
+ *                              separated by commas. Default empty.
+ * @param bool         $append  Optional. If true, don't delete existing tags, just add on. If false,
+ *                              replace the tags with the new tags. Default false.
  * @return array|false|WP_Error Array of affected term IDs. WP_Error or false on failure.
  */
 function wp_set_post_tags( $post_id = 0, $tags = '', $append = false ) {
@@ -3642,11 +3642,12 @@ function wp_set_post_tags( $post_id = 0, $tags = '', $append = false ) {
  *
  * @see wp_set_object_terms()
  *
- * @param int    $post_id  Optional. The Post ID. Does not default to the ID of the global $post.
- * @param string $tags     Optional. The tags to set for the post, separated by commas. Default empty.
- * @param string $taxonomy Optional. Taxonomy name. Default 'post_tag'.
- * @param bool   $append   Optional. If true, don't delete existing tags, just add on. If false,
- *                         replace the tags with the new tags. Default false.
+ * @param int          $post_id  Optional. The Post ID. Does not default to the ID of the global $post.
+ * @param string|array $tags     Optional. An array of terms to set for the post, or a string of terms
+ *                               separated by commas. Default empty.
+ * @param string       $taxonomy Optional. Taxonomy name. Default 'post_tag'.
+ * @param bool         $append   Optional. If true, don't delete existing terms, just add on. If false,
+ *                               replace the terms with the new terms. Default false.
  * @return array|false|WP_Error Array of affected term IDs. WP_Error or false on failure.
  */
 function wp_set_post_terms( $post_id = 0, $tags = '', $taxonomy = 'post_tag', $append = false ) {