MCP TypeScript SDK

The MCP TypeScript SDK is the official TypeScript implementation of the Model Context Protocol — the open standard for connecting LLMs to external tools, data sources, and prompts. It runs on Node.js, Bun, and Deno, and ships server libraries (tools/resources/prompts, Streamable HTTP and stdio transports, auth helpers), client libraries (transports, high-level helpers, OAuth), and thin middleware adapters for Express, Fastify, Hono, and raw Node HTTP. Version 2 (the current stable line) implements the 2026-07-28 MCP spec as the split packages @modelcontextprotocol/server and @modelcontextprotocol/client; the v1 @modelcontextprotocol/sdk package remains on a maintenance branch.

Install the package(s) you need (Node.js, Bun, or Deno — README-verified):

```bash

npm install @modelcontextprotocol/server

# or

npm install @modelcontextprotocol/client

# Bun / Deno equivalents:

bun add @modelcontextprotocol/server

deno add npm:@modelcontextprotocol/server

```

Optional thin middleware adapters for your framework (no new MCP functionality, per README):

```bash

npm install @modelcontextprotocol/express express # Express

npm install @modelcontextprotocol/fastify fastify # Fastify

npm install @modelcontextprotocol/hono hono # Hono

npm install @modelcontextprotocol/node # raw Node http

```

Start with the v2 ten-minute server tutorial: https://ts.sdk.modelcontextprotocol.io/v2/ — runnable examples live in the repo's examples/ directory, and a migration guide covers v1 -> v2.