diff --git a/src/wp-admin/includes/class-wp-automatic-updater.php b/src/wp-admin/includes/class-wp-automatic-updater.php
index 4cf2b0b75b..bc5eaaf536 100644
--- a/src/wp-admin/includes/class-wp-automatic-updater.php
+++ b/src/wp-admin/includes/class-wp-automatic-updater.php
@@ -197,7 +197,29 @@ class WP_Automatic_Updater {
 		 * @since 3.7.0
 		 *
 		 * @param bool   $update Whether to update.
-		 * @param object $item   The update offer.
+		 * @param object $item {
+		 *     The update offer.
+		 *
+		 *     @type string   $current            The version number of the update offer.
+		 *     @type bool     $disable_autoupdate Whether automatic updates for this particular update offer have been
+		 *                                        remotely disabled via the update API response.
+		 *     @type bool     $dismissed          Whether this update offer has previously been dismissed.
+		 *     @type string   $download           URL to the ZIP file for the update.
+		 *     @type string   $locale             Locale of the update offer, eg. `en_US`.
+		 *     @type string   $mysql_version      Minimum required MySQL version for the update.
+		 *     @type object   $packages {
+		 *         URLs for various ZIP packages for the update.
+		 *
+		 *         @type false|string $full
+		 *         @type false|string $no_content
+		 *         @type false|string $new_bundled
+		 *         @type false|string $partial
+		 *         @type false|string $rollback
+		 *     }
+		 *     @type string   $php_version        Minimum required PHP version for the update.
+		 *     @type string   $plugin             File name of the plugin in the update offer, eg. `akismet/akismet.php`.
+		 *     @type string   $theme              Directory name of the theme in the update offer, eg. `twentytwenty`.
+		 * }
 		 */
 		$update = apply_filters( "auto_update_{$type}", $update, $item );