Using MCP Tools with LlamaIndex

LlamaIndex provides robust support for consuming MCP servers through the llama-index-tools-mcp package.

Installation

pip install llama-index-tools-mcp

Basic Usage

The most common usage will be converting an MCP server into a list of llama-index tool definitions:

from llama_index.tools.mcp import BasicMCPClient, McpToolSpec

# Connect to MCP server
mcp_client = BasicMCPClient("http://127.0.0.1:8000/sse")
mcp_tool_spec = McpToolSpec(client=mcp_client)

# Get tools
tools = await mcp_tool_spec.to_tool_list_async()

Using with Agents

Once you have a list of tools, you can plug this into any existing agent:

from llama_index.core.agent.workflow import FunctionAgent
from llama_index.llms.openai import OpenAI

agent = FunctionAgent(
    tools=tools,
    llm=OpenAI(model="gpt-5-mini"),
    system_prompt="You are a helpful assistant.",
)

response = await agent.run("Your query here")

You can read more about agents in the Agents Guide.

Connection Types

The BasicMCPClient supports multiple transport methods:

# Server-Sent Events
sse_client = BasicMCPClient("https://example.com/sse")

# Streamable HTTP
http_client = BasicMCPClient("https://example.com/mcp")

# Local process
local_client = BasicMCPClient("python", args=["server.py"])