Connecting to Multiple MCP Servers

Overview

MCPServerAdapter in crewai-tools allows you to connect to multiple MCP servers concurrently. This is useful when your agents need to access tools distributed across different services or environments. The adapter aggregates tools from all specified servers, making them available to your CrewAI agents.

Configuration

To connect to multiple servers, you provide a list of server parameter dictionaries to MCPServerAdapter. Each dictionary in the list should define the parameters for one MCP server.

Supported transport types for each server in the list include stdio, sse, and streamable-http.

from crewai import Agent, Task, Crew, Process
from crewai_tools import MCPServerAdapter
from mcp import StdioServerParameters # Needed for Stdio example

# Define parameters for multiple MCP servers
server_params_list = [
    # Streamable HTTP Server
    {
        "url": "http://localhost:8001/mcp",
        "transport": "streamable-http"
    },
    # SSE Server
    {
        "url": "http://localhost:8000/sse",
        "transport": "sse"
    },
    # StdIO Server
    StdioServerParameters(
        command="python3",
        args=["servers/your_stdio_server.py"],
        env={"UV_PYTHON": "3.12", **os.environ},
    )
]

try:
    with MCPServerAdapter(server_params_list) as aggregated_tools:
        print(f"Available aggregated tools: {[tool.name for tool in aggregated_tools]}")

        multi_server_agent = Agent(
            role="Versatile Assistant",
            goal="Utilize tools from local Stdio, remote SSE, and remote HTTP MCP servers.",
            backstory="An AI agent capable of leveraging a diverse set of tools from multiple sources.",
            tools=aggregated_tools, # All tools are available here
            verbose=True,
        )

        ... # Your other agent, tasks, and crew code here

except Exception as e:
    print(f"Error connecting to or using multiple MCP servers (Managed): {e}")
    print("Ensure all MCP servers are running and accessible with correct configurations.")

Connection Management

When using the context manager (with statement), MCPServerAdapter handles the lifecycle (start and stop) of all connections to the configured MCP servers. This simplifies resource management and ensures that all connections are properly closed when the context is exited.