diff --git a/src/DependencyInjection/Configuration.php b/src/DependencyInjection/Configuration.php
index a98fb9e..1c96f0e 100644
--- a/src/DependencyInjection/Configuration.php
+++ b/src/DependencyInjection/Configuration.php
@@ -28,8 +28,8 @@ public function getConfigTreeBuilder(): TreeBuilder
                 ->arrayNode('server')
                     ->addDefaultsIfNotSet()
                     ->children()
-                        ->stringNode('name')->defaultValue(self::DEFAULT_NAME)->end()
-                        ->stringNode('version')->defaultValue(self::DEFAULT_VERSION)->end()
+                        ->scalarNode('name')->defaultValue(self::DEFAULT_NAME)->end()
+                        ->scalarNode('version')->defaultValue(self::DEFAULT_VERSION)->end()
                     ->end()
                 ->end()
             ->end();
diff --git a/src/MethodHandler/InitializeMethodHandler.php b/src/MethodHandler/InitializeMethodHandler.php
index 8909c02..35096d6 100644
--- a/src/MethodHandler/InitializeMethodHandler.php
+++ b/src/MethodHandler/InitializeMethodHandler.php
@@ -19,7 +19,7 @@
 #[AsMethodHandler(methodName: 'initialize')]
 class InitializeMethodHandler implements MethodHandlerInterface
 {
-    public const string PROTOCOL_VERSION = '2025-03-26';
+    public const string PROTOCOL_VERSION = '2024-11-05';
 
     public function __construct(
         private readonly string $serverName,
diff --git a/src/Service/ResponseFactory.php b/src/Service/ResponseFactory.php
index c872f5b..85434a7 100644
--- a/src/Service/ResponseFactory.php
+++ b/src/Service/ResponseFactory.php
@@ -46,6 +46,7 @@ private function createResponse(JsonRpcResponse $response): JsonResponse
     {
         $json = $this->serializer->serialize($response, 'json', [
             AbstractObjectNormalizer::SKIP_NULL_VALUES => true,
+            AbstractObjectNormalizer::PRESERVE_EMPTY_OBJECTS => true,
         ]);
 
         return JsonResponse::fromJsonString($json, JsonResponse::HTTP_OK);