modelcontextprotocol/typescript-sdk

It solves the fragmentation of LLM context integration by providing a unified protocol and SDK, enabling developers to build reusable context providers and clients without coupling to specific LLM APIs. This standardizes tool, resource, and prompt schemas using Standard Schema, allowing interoperability across different LLM applications.

Developers can build MCP servers that expose tools, resources, and prompts to LLMs, and MCP clients that connect to these servers. Real-world use cases include creating custom knowledge bases, API wrappers, or automation tools that LLMs can invoke. The ceiling includes complex multi-server setups with authentication, streaming, and integration with web frameworks like Express, Fastify, and Hono.