Fixing MCP initialization

app.py

@@ -4,6 +4,7 @@ from mcp.client.stdio import StdioServerParameters
 from smolagents import InferenceClientModel, CodeAgent, ToolCollection
 from smolagents.mcp_client import MCPClient
 
+mcp_client = None
 try:
     mcp_client = MCPClient(
         # Try this working example on the hub:
@@ -25,4 +26,5 @@ try:
 
     demo.launch()
 finally:
-    mcp_client.disconnect()
+    if mcp_client:
+        mcp_client.disconnect()