diff --git a/src/SchemaNormalizer.php b/src/SchemaNormalizer.php
index 6278554a..d21d1932 100644
--- a/src/SchemaNormalizer.php
+++ b/src/SchemaNormalizer.php
@@ -98,7 +98,6 @@ public function normalize(string $json): string
             ));
         }
 
-        /** @var array|\stdClass $normalized */
         $normalized = $this->normalizeData(
             $decoded,
             $schema
@@ -115,12 +114,12 @@ public function normalize(string $json): string
     }
 
     /**
-     * @param array|bool|float|int|\stdClass|string $data
-     * @param \stdClass                             $schema
+     * @param null|array|bool|float|int|\stdClass|string $data
+     * @param \stdClass                                  $schema
      *
      * @throws \InvalidArgumentException
      *
-     * @return array|bool|float|int|\stdClass|string
+     * @return null|array|bool|float|int|\stdClass|string
      */
     private function normalizeData($data, \stdClass $schema)
     {
diff --git a/src/Validator/SchemaValidatorInterface.php b/src/Validator/SchemaValidatorInterface.php
index e9f34f12..1d240628 100644
--- a/src/Validator/SchemaValidatorInterface.php
+++ b/src/Validator/SchemaValidatorInterface.php
@@ -16,8 +16,8 @@
 interface SchemaValidatorInterface
 {
     /**
-     * @param array|\stdClass $data
-     * @param \stdClass       $schema
+     * @param null|array|bool|float|int|\stdClass|string $data
+     * @param \stdClass                                  $schema
      *
      * @return bool
      */