deer-flow/backend/src/mcp/tools.py

"""Load MCP tools using langchain-mcp-adapters."""

import logging

from langchain_core.tools import BaseTool

from src.config.extensions_config import get_extensions_config
from src.mcp.client import build_servers_config

logger = logging.getLogger(__name__)


async def get_mcp_tools() -> list[BaseTool]:
    """Get all tools from enabled MCP servers.

    Returns:
        List of LangChain tools from all enabled MCP servers.
    """
    try:
        from langchain_mcp_adapters.client import MultiServerMCPClient
    except ImportError:
        logger.warning("langchain-mcp-adapters not installed. Install it to enable MCP tools: pip install langchain-mcp-adapters")
        return []

    extensions_config = get_extensions_config()
    servers_config = build_servers_config(extensions_config)

    if not servers_config:
        logger.info("No enabled MCP servers configured")
        return []

    try:
        # Create the multi-server MCP client
        logger.info(f"Initializing MCP client with {len(servers_config)} server(s)")
        client = MultiServerMCPClient(servers_config)

        # Get all tools from all servers
        tools = await client.get_tools()
        logger.info(f"Successfully loaded {len(tools)} tool(s) from MCP servers")

        return tools

    except Exception as e:
        logger.error(f"Failed to load MCP tools: {e}", exc_info=True)
        return []