diff --git a/src/Request/Frame/Body.php b/src/Request/Frame/Body.php
index 88aa8dc..f19fb7a 100644
--- a/src/Request/Frame/Body.php
+++ b/src/Request/Frame/Body.php
@@ -41,7 +41,7 @@ public static function of(Maybe $headers): Frame
     }
 
     /**
-     * @param positive-int $length
+     * @param int<1, max> $length
      *
      * @return Frame<Sequence<Str>>
      */