diff --git a/Models/Tag.php b/Models/Tag.php
index 1678e0d..fa34374 100755
--- a/Models/Tag.php
+++ b/Models/Tag.php
@@ -164,7 +164,7 @@ class Tag implements \JsonSerializable, ArrayableInterface
     /**
      * {@inheritdoc}
      */
-    public function jsonSerialize()
+    public function jsonSerialize() : mixed
     {
         return $this->toArray();
     }
diff --git a/Models/TagL11n.php b/Models/TagL11n.php
index b7ef869..34c21c4 100755
--- a/Models/TagL11n.php
+++ b/Models/TagL11n.php
@@ -126,7 +126,7 @@ class TagL11n implements \JsonSerializable, ArrayableInterface
     /**
      * {@inheritdoc}
      */
-    public function jsonSerialize()
+    public function jsonSerialize() : mixed
     {
         return $this->toArray();
     }