diff --git a/api/core/mcp/auth_client.py b/api/core/mcp/auth_client.py
index bbf18ab780..7613c2733c 100644
--- a/api/core/mcp/auth_client.py
+++ b/api/core/mcp/auth_client.py
@@ -180,7 +180,9 @@ class MCPClientWithAuthRetry(MCPClient):
         """
         return self._execute_with_retry(super().list_tools)
 
-    def invoke_tool(self, tool_name: str, tool_args: dict[str, Any], _meta: dict[str, Any] | None = None) -> CallToolResult:
+    def invoke_tool(
+        self, tool_name: str, tool_args: dict[str, Any], _meta: dict[str, Any] | None = None
+    ) -> CallToolResult:
         """
         Invoke a tool on the MCP server with auth retry.
 
diff --git a/api/core/mcp/mcp_client.py b/api/core/mcp/mcp_client.py
index 5e9f1f4058..5929204ecb 100644
--- a/api/core/mcp/mcp_client.py
+++ b/api/core/mcp/mcp_client.py
@@ -96,7 +96,9 @@ class MCPClient:
         response = self._session.list_tools()
         return response.tools
 
-    def invoke_tool(self, tool_name: str, tool_args: dict[str, Any], _meta: dict[str, Any] | None = None) -> CallToolResult:
+    def invoke_tool(
+        self, tool_name: str, tool_args: dict[str, Any], _meta: dict[str, Any] | None = None
+    ) -> CallToolResult:
         """Call a tool"""
         if not self._session:
             raise ValueError("Session not initialized.")