diff --git a/src/wp-includes/class-wp-theme-json.php b/src/wp-includes/class-wp-theme-json.php
index 1af02531cc1a1..11f547ae5a94d 100644
--- a/src/wp-includes/class-wp-theme-json.php
+++ b/src/wp-includes/class-wp-theme-json.php
@@ -313,10 +313,12 @@ class WP_Theme_JSON {
 	 * @since 5.8.0 As `ALLOWED_TOP_LEVEL_KEYS`.
 	 * @since 5.9.0 Renamed from `ALLOWED_TOP_LEVEL_KEYS` to `VALID_TOP_LEVEL_KEYS`,
 	 *              added the `customTemplates` and `templateParts` values.
+	 * @since 6.3.0 Added the `description` value.
 	 * @var string[]
 	 */
 	const VALID_TOP_LEVEL_KEYS = array(
 		'customTemplates',
+		'description',
 		'patterns',
 		'settings',
 		'styles',