diff --git a/src/Psalm/Internal/Fork/PsalmRestarter.php b/src/Psalm/Internal/Fork/PsalmRestarter.php
index 6d1dada4c3a..08154a47cb4 100644
--- a/src/Psalm/Internal/Fork/PsalmRestarter.php
+++ b/src/Psalm/Internal/Fork/PsalmRestarter.php
@@ -125,7 +125,7 @@ private static function toBytes(string $value): int
     /**
      * No type hint to allow xdebug-handler v1 and v2 usage
      *
-     * @param string[] $command
+     * @param non-empty-list<string> $command
      * @phpcsSuppress SlevomatCodingStandard.TypeHints.ParameterTypeHint.MissingNativeTypeHint
      */
     protected function restart($command): void
@@ -167,6 +167,7 @@ protected function restart($command): void
             0,
             $additional_options,
         );
+        assert(count($command) > 1);
 
         parent::restart($command);
     }