diff --git a/composer.json b/composer.json
index 8871dd7..7704667 100644
--- a/composer.json
+++ b/composer.json
@@ -10,10 +10,10 @@
         }
     ],
     "require": {
-        "php": "^7.4 || ^8.0"
+        "php": "^7.4 || ^8.0",
+        "vimeo/psalm": "^4.6"
     },
     "require-dev": {
-        "vimeo/psalm": "^4.6",
         "friendsofphp/php-cs-fixer": "^2.18",
         "roave/security-advisories": "dev-master",
         "squizlabs/php_codesniffer": "^3.5"
@@ -52,4 +52,4 @@
         }
     },
     "minimum-stability": "dev"
-}
+}
\ No newline at end of file
diff --git a/src/Argument.php b/src/Argument.php
index e3bad64..be72b38 100644
--- a/src/Argument.php
+++ b/src/Argument.php
@@ -12,7 +12,7 @@ final class Argument
 {
     /**
      * @param list<PhpParser\Node\Arg> $arguments
-     * @param int<0, max> $index
+     * @param 0|positive-int $index
      */
     public static function getType(
         array $arguments,