diff --git a/src/Provider/AbstractProvider.php b/src/Provider/AbstractProvider.php
index eb624176..ef970e77 100644
--- a/src/Provider/AbstractProvider.php
+++ b/src/Provider/AbstractProvider.php
@@ -615,7 +615,7 @@ protected function getAccessTokenRequest(array $params)
     /**
      * Requests an access token using a specified grant and option set.
      *
-     * @param  mixed                $grant
+     * @param  AbstractGrant|string $grant
      * @param  array<string, mixed> $options
      * @return AccessTokenInterface
      * @throws IdentityProviderException