fix: remove pycache files and finalize integration

mcp_client.py

@@ -5,7 +5,7 @@ Enables integration with MCP servers like skills.sh to discover and use tools
 import json
 import requests
 from typing import Dict, List, Any, Optional
-from langchain.tools import Tool
+from langchain_core.tools import Tool
 import logging
 
 logger = logging.getLogger(__name__)
@@ -97,6 +97,7 @@ class MCPClient:
             return self._available_tools
         except Exception as e:
             logger.error(f"Failed to list tools from MCP server {self.server_url}: {e}")
+            self._available_tools = []
             return []
     
     def call_tool(self, tool_name: str, arguments: Dict[str, Any]) -> Any: