diff --git a/src/Entities/AccessTokenEntityInterface.php b/src/Entities/AccessTokenEntityInterface.php
index 8cc20dd2..5d69eefd 100644
--- a/src/Entities/AccessTokenEntityInterface.php
+++ b/src/Entities/AccessTokenEntityInterface.php
@@ -9,17 +9,12 @@
 
 namespace League\OAuth2\Server\Entities;
 
-use Lcobucci\JWT\Token;
 use League\OAuth2\Server\CryptKey;
 
 interface AccessTokenEntityInterface extends TokenInterface
 {
     /**
      * Generate a string representation from the access token
-     *
-     * @param CryptKey $privateKey
-     *
-     * @return string
      */
-    public function convertToAccessToken(CryptKey $privateKey);
+    public function convertToAccessToken(CryptKey $privateKey): string;
 }
diff --git a/src/Entities/Traits/AccessTokenTrait.php b/src/Entities/Traits/AccessTokenTrait.php
index 08231784..fab41c46 100644
--- a/src/Entities/Traits/AccessTokenTrait.php
+++ b/src/Entities/Traits/AccessTokenTrait.php
@@ -42,12 +42,8 @@ trait AccessTokenTrait
 
     /**
      * Generate a string representation from the access token
-     *
-     * @param CryptKey $privateKey
-     *
-     * @return string
      */
-    public function convertToAccessToken(CryptKey $privateKey)
+    public function convertToAccessToken(CryptKey $privateKey): string
     {
         return (string) $this->convertToJWT($privateKey);
     }