MCP TypeScript SDK (V2) / @modelcontextprotocol/server

@modelcontextprotocol/server

The MCP (Model Context Protocol) TypeScript server SDK. Build MCP servers that expose tools, resources, and prompts.

This is v2 of the MCP TypeScript SDK, the stable release line, implementing the 2026-07-28 MCP spec. It replaces the single @modelcontextprotocol/sdk package from v1. Start with the documentation; coming from v1, see the migration guide. Found a problem? Open an issue.

Install

npm install @modelcontextprotocol/server

TypeScript ≥6.0 no longer auto-includes @types/* — add "types": ["node"] to your tsconfig.json compilerOptions (the published .d.mts references Buffer).

Optional framework adapters: @modelcontextprotocol/express, @modelcontextprotocol/fastify, @modelcontextprotocol/hono, @modelcontextprotocol/node.

Documentation

• Repository README — overview, package layout, examples
• Server guide — tools, resources, prompts, and the rest of the server surface
• Serving guide — stdio, HTTP, the framework adapters, sessions, and authorization
• API reference
• MCP specification

Modules

• fromJsonSchema
• index
• server/completable
• server/completable.examples
• server/createMcpHandler
• server/invoke
• server/legacyInputRequiredShim
• server/listenRouter
• server/mcp
• server/mcp.examples
• server/middleware/bearerAuth
• server/middleware/bearerAuth.examples
• server/middleware/hostHeaderValidation
• server/middleware/hostHeaderValidation.examples
• server/middleware/oauthMetadata
• server/middleware/oauthMetadata.examples
• server/middleware/originValidation
• server/perRequestTransport
• server/requestBody
• server/requestStateCodec
• server/scopeChallenge
• server/server
• server/serverEventBus
• server/serveStdio
• server/sseKeepAlive
• server/stdio
• server/stdio.examples
• server/streamableHttp
• server/streamableHttp.examples
• shimsBrowser
• shimsNode
• shimsWorkerd
• stdio
• validators/ajv
• validators/cfWorker