diff --git a/src/Link/Metadata/MetadataObject.php b/src/Link/Metadata/MetadataObject.php
index 2f124f7..da124f1 100644
--- a/src/Link/Metadata/MetadataObject.php
+++ b/src/Link/Metadata/MetadataObject.php
@@ -3,8 +3,11 @@
 namespace Hyvor\Unfold\Link\Metadata;
 
 
+use Hyvor\Unfold\Unfolded\UnfoldedAuthor;
+use Hyvor\Unfold\Unfolded\UnfoldedTag;
+
 /**
- * @template T extends string|DateTimeInterface|UnfoldedAuthor|UnfoldedTag
+ * @template T of string|\DateTimeInterface|UnfoldedAuthor|UnfoldedTag = string
  */
 class MetadataObject
 {
diff --git a/src/Link/Metadata/MetadataPriority.php b/src/Link/Metadata/MetadataPriority.php
index 15f451d..5127d5e 100644
--- a/src/Link/Metadata/MetadataPriority.php
+++ b/src/Link/Metadata/MetadataPriority.php
@@ -56,7 +56,7 @@ private function prioritizedAll(array $keys)
          *    'OG_TITLE' => [MetadataObject],
          * ]
          */
-        $keysNames = array_map(fn($key) => $key->name, $keys);
+        $keysNames = array_map(fn ($key) => $key->name, $keys);
         uksort($keyedMetadata, function ($a, $b) use ($keysNames) {
             return array_search($a, $keysNames) - array_search($b, $keysNames);
         });
@@ -64,7 +64,7 @@ private function prioritizedAll(array $keys)
         // index by 0,1,2
         $keyedMetadata = array_values($keyedMetadata);
         // return the values
-        return array_map(fn($metadata) => $metadata->value, $keyedMetadata[0] ?? []);
+        return array_map(fn ($metadata) => $metadata->value, $keyedMetadata[0] ?? []);
     }
 
     /**
@@ -144,7 +144,7 @@ public function siteUrl(string $url): ?string
             return $host ? $scheme . '://' . $host : null;
         }
 
-        return null; // @ignoreCodeCoverage
+        return null; // @codeCoverageIgnore
     }
 
 
diff --git a/src/Unfold.php b/src/Unfold.php
index 22aabad..e9cf45e 100644
--- a/src/Unfold.php
+++ b/src/Unfold.php
@@ -30,6 +30,7 @@ public static function unfold(
         } else {
             // both
             // TODO:
+            throw new \Exception('Not implemented yet');
         }
     }
 }