diff --git a/lib/galaxy/tool_util/verify/interactor.py b/lib/galaxy/tool_util/verify/interactor.py
index 1a286758c45f..da4bf13baf3b 100644
--- a/lib/galaxy/tool_util/verify/interactor.py
+++ b/lib/galaxy/tool_util/verify/interactor.py
@@ -819,7 +819,7 @@ def __submit_tool(self, history_id, tool_id, tool_input, extra_data=None, files=
         data = dict(
             history_id=history_id, tool_id=tool_id, inputs=dumps(tool_input), tool_version=tool_version, **extra_data
         )
-        return self._post("tools", files=files, data=data, json=True)
+        return self._post("tools", files=files, data=data)
 
     def ensure_user_with_email(self, email, password=None):
         admin_key = self.master_api_key