Mcp Nest

MCP Nest is a ready‑to‑use NestJS module that turns any Nest application into a fully‑featured Model Context Protocol server. By leveraging the familiar dependency‑injection patterns of Nest, developers can expose their business logic as AI‑ready tools, serve data through a resource system, and craft reusable prompt templates—all without writing boilerplate MCP code. This integration solves the pain of bridging complex backend services to AI assistants, allowing teams to reuse existing codebases and infrastructure while providing a clean, typed interface for agents.

The server offers multi‑transport support, enabling communication over HTTP with Server‑Sent Events, streamable HTTP responses, or even STDIO. This flexibility means the same MCP instance can serve web clients, command‑line tools, or embedded systems. Tools are automatically discovered and validated with Zod, ensuring that input schemas are enforced at runtime. Interactive tool calls let agents request additional user input on the fly, while progress notifications keep users informed during long operations. Full access to the HTTP request context inside tool handlers further enhances integration with authentication, logging, or other middleware.

A powerful resource system allows static files and dynamic data to be served directly through MCP URIs. Parameterized resource templates enable developers to expose APIs that accept path variables, turning simple data endpoints into AI‑friendly resources. Complementing this is a prompt system that lets you define and reuse prompt templates, reducing duplication and keeping conversational logic consistent across tools.

Security is built into the stack with guard‑based authentication, OAuth support, and an optional built‑in authorization server (currently in beta) that can be swapped for external providers like Keycloak or Auth0. This means you can enforce fine‑grained access control without leaving the Nest ecosystem.

In practice, MCP Nest shines in scenarios where an AI assistant needs to orchestrate complex business workflows—such as generating invoices, querying inventory, or initiating approvals—while maintaining strong typing, security, and observability. By embedding the MCP server inside a Nest application, teams can deliver AI‑enabled features that are as reliable and maintainable as their traditional services.