diff --git a/src/CloudflarePagesMiddleware.php b/src/CloudflarePagesMiddleware.php
index 8d8bc39..19ff02f 100644
--- a/src/CloudflarePagesMiddleware.php
+++ b/src/CloudflarePagesMiddleware.php
@@ -10,7 +10,7 @@
 
 class CloudflarePagesMiddleware
 {
-    public function handle(Request $request, Closure $next, $ttl, $tags): Response
+    public function handle(Request $request, Closure $next, string $ttl, string $tags): Response
     {
         /** @var Response $response */
         $response = $next($request);