diff --git a/src/LiveComponent/src/Hydration/HydrationExtensionInterface.php b/src/LiveComponent/src/Hydration/HydrationExtensionInterface.php
index 9b7b0202243..3a62a6c9baa 100644
--- a/src/LiveComponent/src/Hydration/HydrationExtensionInterface.php
+++ b/src/LiveComponent/src/Hydration/HydrationExtensionInterface.php
@@ -13,8 +13,14 @@
 
 interface HydrationExtensionInterface
 {
+    /**
+     * @param class-string $className
+     */
     public function supports(string $className): bool;
 
+    /**
+     * @param class-string $className
+     */
     public function hydrate(mixed $value, string $className): ?object;
 
     /**