MCPX Anthropic Client

This library allows you connect your Anthropic models to mcp.run and expose your installed servlets as tools which can be invoked in process (without spinning up many server processes).

Usage

Install

You just need the mcpx-anthropic library and the anthropic library (if you don't already have it).

npm install @dylibso/mcpx-anthropic @anthropic-ai/sdk

To get an mcp.run session id, run this command and follow the instructions:

npx --yes -p @dylibso/mcpx@latest gen-session

Code

This package exports a message driver designed to wrap the Anthropic createMessage API:

import Anthropic from "@anthropic-ai/sdk";
import createDriver from "@dylibso/mcpx-anthropic"

const anthropic = new Anthropic({
  apiKey: process.env.ANTHROPIC_API_KEY
})

const mcpx = await createDriver({
  anthropic,
  sessionId: process.env.MCP_RUN_SESSION_ID,
})

const messages = [];

// call any tool compatible api, e.g chat completion:
// let's ask it to evalute some javascript. If you have
// this tool installed: https://www.mcp.run/bhelx/eval-js it should
// determine and use this to evaluate it in a sandbox
messages.push({
  role: 'user',
  content: `
    Write a djb2hash function in javascript and evalute it on the string "Hello, World!"
  `
});

// this will automatically process all tool calls
// until there are none left
const response = await mcpx.createMessage({
  max_tokens: 1024,
  messages,
  model: 'claude-3-5-sonnet-latest',
});

console.log(response.content)
//=> The DJB2 hash of the string "Hello, World!" is `-1763540338`.

Examples

• Example chat application