diff --git a/src/Filter.php b/src/Filter.php
index 9112a67..5500cca 100644
--- a/src/Filter.php
+++ b/src/Filter.php
@@ -12,7 +12,7 @@
 
 final class Filter
 {
-    /** @var array<int, FormInterface> */
+    /** @var array<int|string, FormInterface> */
     private array $forms;
 
     public function __construct(private FormFactoryInterface $formFactory, private RequestStack $requestStack)