diff --git a/app/Http/Controllers/Api/ExecutionController.php b/app/Http/Controllers/Api/ExecutionController.php
index bbab7d4..a1f46ab 100644
--- a/app/Http/Controllers/Api/ExecutionController.php
+++ b/app/Http/Controllers/Api/ExecutionController.php
@@ -17,6 +17,7 @@ class ExecutionController extends Controller
             'project_id' => 'required|exists:projects,id',
             'input' => 'required|string',
             'output' => 'required|string',
+            'cost' => 'required|string',
         ]);
 
         $project = Project::find($request->project_id);