Creativity · MCP — integration

MCP + Anthropic SDK Integration

The Anthropic SDK accepts MCP-style tool definitions natively in 2026. A developer points the SDK at one or more MCP servers, the SDK advertises those servers' tools to Claude, and when Claude chooses to call a tool the SDK routes the request back to the MCP server, streams the result, and feeds it into the next model turn. This is the standard path for building custom agents on top of Claude Opus 4 and Sonnet 4.

MCP facts

Kind: integration
Ecosystem: anthropic-mcp
Language: Python / TypeScript
Transports: stdio, http

Capabilities

Register one or more MCP servers with an Anthropic client session
Auto-advertise tools and resources to the Messages API
Route tool calls back to the appropriate MCP server and stream results
Compatible with prompt caching and extended context windows

Install

pip install anthropic mcp # or: npm i @anthropic-ai/sdk @modelcontextprotocol/sdk

Configuration

from anthropic import Anthropic
from anthropic.mcp import StdioServer

client = Anthropic()
fs = StdioServer(command="npx", args=["-y", "@modelcontextprotocol/server-filesystem", "./repo"])

resp = client.messages.create(
    model="claude-opus-4-7",
    max_tokens=1024,
    mcp_servers=[fs],
    messages=[{"role": "user", "content": "Summarise the repo's README."}],
)

Frequently asked questions

Does the SDK auto-handle the tool-use loop?

Yes — when you pass mcp_servers, the SDK handles tool_use/tool_result round-trips internally and returns the final assistant message to the caller.

Can I mix MCP and inline tools?

Yes — pass both `tools=[...]` and `mcp_servers=[...]`. The SDK merges them. This is common when you want MCP servers for reusable capabilities and inline tools for app-specific logic.

What about prompt caching?

Anthropic's cache-control blocks still apply. Cache MCP tool schemas alongside system instructions to reduce per-turn token cost in long sessions.

Sources

Anthropic Python SDK — accessed 2026-04-20
Anthropic TypeScript SDK — accessed 2026-04-20
MCP specification — accessed 2026-04-20