diff --git a/src/Support/Generator/Types/Type.php b/src/Support/Generator/Types/Type.php
index 191335dfc..2f4cb4e0d 100644
--- a/src/Support/Generator/Types/Type.php
+++ b/src/Support/Generator/Types/Type.php
@@ -57,7 +57,8 @@ public function addProperties(Type $fromType)
     public function toArray()
     {
         return array_merge(array_filter([
-            'type' => $this->nullable ? [$this->type, 'null'] : $this->type,
+            'type' => $this->type,
+            'nullable' => $this->nullable,
             'format' => $this->format,
             'description' => $this->description,
             'enum' => count($this->enum) ? $this->enum : null,