MCP TypeScript Template

A TypeScript template for building remote Model Context Protocol (MCP) servers with modern tooling and best practices while leveraging the MCP TypeScript SDK.

Features

This template provides:

• TypeScript 7 - Native compiler with strict configuration; TypeScript 6 remains available for typescript-eslint's compiler API

• Effect - Typed configuration, validation, logging, error handling, and async workflows

• Vite - Fast build system with ES modules output

• Express - Fast, unopinionated web framework for HTTP server

• ESLint + Prettier - Code quality and formatting

• Docker - Containerization support

• Example Tools - echo and elicit_echo tools demonstrating tool implementation, structured output, annotations, and MCP elicitation

Related MCP server: MCP Server Boilerplate

Getting Started

The easiest way to get started is using degit:

1. Create a new project from this template

   npx degit nickytonline/mcp-typescript-template my-mcp-server
   cd my-mcp-server

2. Install dependencies

   npm install

3. Build the project

   npm run build

4. Start the server

   npm start

The server will be available at http://localhost:3000 for MCP connections.

Alternative: Using GitHub Template

You can also click the "Use this template" button on GitHub to create a new repository, then clone it:

git clone <your-repo-url>
cd my-mcp-server
npm install

Development

Type checking

npm run typecheck uses the TypeScript 7 compiler. The typescript package is an npm alias for the TypeScript 6 compatibility package because typescript-eslint still depends on TypeScript's legacy compiler API; the compatibility package is available as tsc6 when needed.

Watch mode for development (with hot reloading)

npm run dev

Build the project

npm run build

Linting

• Lint the project

npm run lint

• Fix all auto-fixable lint errors

npm run lint:fix

Formatting

• Format files in the project

npm run format

• Check formatting

npm run format:check

Testing Your MCP Server

You can test your MCP server using the MCP Inspector:

npx @modelcontextprotocol/inspector

This will launch a web interface that allows you to:

• Connect to your MCP server

• Test your tools interactively

• View request/response messages

• Debug your MCP implementation

Make sure your server is running (using npm start or npm run dev) before connecting with the inspector.

Available Tools

The template includes two example tools:

echo

Echoes back the provided message - a simple example to demonstrate MCP tool implementation.

Parameters:

• message (string) - The message to echo back

elicit_echo

Demonstrates MCP elicitation: the tool takes no input, asks the connected client to prompt the user for a message, then echoes it back. Handles all three elicitation outcomes (accept, decline, cancel) and errors when the client doesn't support elicitation.

Both tools declare an outputSchema and return structuredContent alongside the text result, and carry annotations (readOnlyHint, idempotentHint, openWorldHint) describing their safety profile.

Customizing Your MCP Server

1. Update package.json - Change name, description, and keywords

2. Modify src/tools.ts - Replace the echo / elicit_echo tools with your custom tools

3. Add your logic - Create additional TypeScript files for your business logic

4. Update README - Document your specific MCP server functionality

Docker

Build and run using Docker:

• Build the Docker image

docker build -t my-mcp-server .

• Run the container

docker run -p 3000:3000 my-mcp-server

Docker Compose

A docker-compose.yml is included with a health check pre-configured:

docker compose up --build

Project Structure

mcp-typescript-template/
├── src/
│   ├── app.ts            # Express app and MCP Node adapter wiring
│   ├── app.test.ts       # HTTP boundary integration tests
│   ├── index.ts          # Effect startup and shutdown
│   ├── tools.ts          # Tool registration (registerTools) and logic
│   ├── tools.test.ts     # Integration tests (in-memory client/server)
│   ├── config.ts         # Env var loading and validation (Effect Config)
│   ├── logger.ts         # Effect structured logging
│   └── lib/
│       ├── utils.ts      # MCP response helpers
│       ├── mcp-schema.ts  # Effect Schema → MCP Standard Schema adapter
│       ├── utils.test.ts # Unit tests
│       └── mcp-schema.test.ts # Schema adapter and dialect tests
├── dist/                 # Built output (generated)
├── tsconfig.json         # TypeScript configuration
├── vite.config.ts        # Vite build configuration
├── eslint.config.js      # ESLint configuration
├── Dockerfile            # Docker configuration
└── package.json          # Dependencies and scripts

Architecture

This template follows a simple architecture:

• HTTP Transport - Uses Express with createMcpHandler (@modelcontextprotocol/server) for remote MCP connections

• Stateless - Per the MCP 2026-07-28 spec: no session handshake or session ID; the app creates a fresh server per request and supports older clients through the SDK fallback

• Tool Registration - registerTools(server) in src/tools.ts is the single source of truth for tool wiring; getServer() and the tests both use it

• Typed I/O - Effect Schema inputSchema/outputSchema values adapted to MCP Standard Schema, plus structuredContent for typed results

• JSON Schema Dialects - The adapter supports both MCP-requested draft-07 and draft-2020-12 output

• Error Handling - Genuine tool execution failures return isError: true via createErrorResult rather than being thrown; protocol, transport, and capability failures (e.g. an unsupported elicitation) can still reject the client call

• Health Check - GET /health is a plain liveness endpoint (used by the Docker health check); GET /mcp is routed to the MCP handler itself

Example: Adding a New Tool

Add the registration inside registerTools() in src/tools.ts. See the create-mcp-tool skill (.agents/skills/create-mcp-tool) for the full walkthrough.

import type { CallToolResult, ServerContext } from "@modelcontextprotocol/server";
import { Effect, Schema } from "effect";
import { toMcpSchema } from "./lib/mcp-schema.ts";
import { createTextResult, runMcpEffect } from "./lib/utils.ts";

server.registerTool(
  "my_tool",
  {
    title: "My Custom Tool",
    description: "Description of what this tool does",
    inputSchema: toMcpSchema(
      Schema.Struct({
        param1: Schema.String,
        param2: Schema.optional(Schema.Number),
      }),
    ),
    outputSchema: toMcpSchema(Schema.Struct({ output: Schema.String })),
    annotations: { readOnlyHint: true, openWorldHint: false },
  },
  (args, ctx) => runMcpEffect(myTool(args, ctx)),
);

function myTool(
  args: { param1: string; param2?: number },
  _ctx: ServerContext,
): Effect.Effect<CallToolResult> {
  return Effect.succeed(createTextResult({ output: args.param1 }));
}

Keep the tool workflow in Effect and use runMcpEffect() only where it crosses back into the MCP SDK callback API. For asynchronous work, use Effect.tryPromise; for independent parallel work, use Effect.all with explicit concurrency.

Why Express?

This template uses Express for the HTTP server, which provides:

• MCP SDK Compatibility - Full compatibility with @modelcontextprotocol/server's createMcpHandler, adapted to Node/Express via @modelcontextprotocol/node's toNodeHandler

• Mature & Stable - Battle-tested HTTP server with extensive ecosystem

• TypeScript Support - Excellent TypeScript support with comprehensive type definitions

• Middleware Ecosystem - Rich ecosystem of middleware for common tasks

• Documentation - Comprehensive documentation and community support

• Reliability - Proven reliability for production applications

Repository Guidelines

Contributors should review AGENTS.md for project structure, coding standards, and pull request expectations before opening changes.