diff -r 48c4eec2b7e6 -r 8c2e4d02f4ef wp/wp-includes/ms-site.php
--- a/wp/wp-includes/ms-site.php	Fri Sep 05 18:40:08 2025 +0200
+++ b/wp/wp-includes/ms-site.php	Fri Sep 05 18:52:52 2025 +0200
@@ -439,8 +439,8 @@
  *
  * @param string|array $args Optional. Array or string of arguments. See WP_Site_Query::__construct()
  *                           for information on accepted arguments. Default empty array.
- * @return array|int List of WP_Site objects, a list of site IDs when 'fields' is set to 'ids',
- *                   or the number of sites when 'count' is passed as a query var.
+ * @return WP_Site[]|int[]|int List of WP_Site objects, a list of site IDs when 'fields' is set to 'ids',
+ *                             or the number of sites when 'count' is passed as a query var.
  */
 function get_sites( $args = array() ) {
 	$query = new WP_Site_Query();
@@ -1026,7 +1026,13 @@
  *
  * @param int    $site_id    Site ID.
  * @param string $meta_key   Metadata name.
- * @param mixed  $meta_value Metadata value. Must be serializable if non-scalar.
+ * @param mixed  $meta_value Metadata value. Arrays and objects are stored as serialized data and
+ *                           will be returned as the same type when retrieved. Other data types will
+ *                           be stored as strings in the database:
+ *                           - false is stored and retrieved as an empty string ('')
+ *                           - true is stored and retrieved as '1'
+ *                           - numbers (both integer and float) are stored and retrieved as strings
+ *                           Must be serializable if non-scalar.
  * @param bool   $unique     Optional. Whether the same key should not be added.
  *                           Default false.
  * @return int|false Meta ID on success, false on failure.
@@ -1069,7 +1075,13 @@
  * @return mixed An array of values if `$single` is false.
  *               The value of meta data field if `$single` is true.
  *               False for an invalid `$site_id` (non-numeric, zero, or negative value).
- *               An empty string if a valid but non-existing site ID is passed.
+ *               An empty array if a valid but non-existing site ID is passed and `$single` is false.
+ *               An empty string if a valid but non-existing site ID is passed and `$single` is true.
+ *               Note: Non-serialized values are returned as strings:
+ *               - false values are returned as empty strings ('')
+ *               - true values are returned as '1'
+ *               - numbers (both integer and float) are returned as strings
+ *               Arrays and objects retain their original type.
  */
 function get_site_meta( $site_id, $key = '', $single = false ) {
 	return get_metadata( 'blog', $site_id, $key, $single );