diff --git a/src/Providers/Mistral/Maps/ToolMap.php b/src/Providers/Mistral/Maps/ToolMap.php
index 1b8a0e532..28bba3c84 100644
--- a/src/Providers/Mistral/Maps/ToolMap.php
+++ b/src/Providers/Mistral/Maps/ToolMap.php
@@ -21,7 +21,7 @@ public static function map(array $tools): array
                 'description' => $tool->description(),
                 'parameters' => [
                     'type' => 'object',
-                    'properties' => $tool->parametersAsArray(),
+                    'properties' => $tool->parametersAsArray() ?: (object) [],
                     'required' => $tool->requiredParameters(),
                 ],
             ],