My HTTP Server

A small Model Context Protocol (MCP) server built with:

• @modelcontextprotocol/sdk
• express
• typescript
• zod

The app exposes a Streamable HTTP MCP endpoint at /mcp and includes a few example tools, resources, and prompts centered around cryptocurrency data.

Project Structure

src/
  server.ts
  http/
    createMcpApp.ts
  mcp/
    createMcpServer.ts
  services/
    cryptoService.ts

Responsibilities

• src/server.ts Starts the HTTP server and wires the app together.

• src/http/createMcpApp.ts Contains the HTTP and MCP transport boilerplate: request parsing, origin validation, session management, and /mcp route handling.

• src/mcp/createMcpServer.ts Defines the MCP server itself: tools, resources, prompts, and their schemas.

• src/services/cryptoService.ts Contains the business logic for symbol normalization, Binance API calls, and activity log access.

Features

The server currently registers:

• Tools: ping, add_numbers, get_price, get_price_change

• Resources: activity_log, crypto_price

• Prompt: executive_summary

The crypto-related tools call Binance's public market-data endpoints and append activity to activity.log.

Requirements

• Node.js 20+
• npm

Node 20+ is recommended because the app relies on the built-in fetch API.

Install

npm install

Run

Start the server directly from TypeScript with tsx:

npx tsx src/server.ts

By default, the server listens on:

http://127.0.0.1:8787/mcp

You can override the port with PORT:

PORT=3000 npx tsx src/server.ts

Build / Type Check

This repo does not currently include a tsconfig.json or build script, so the simplest way to validate the TypeScript sources is:

npx tsc --noEmit --module nodenext --moduleResolution nodenext --target es2022 --esModuleInterop src/server.ts src/http/createMcpApp.ts src/mcp/createMcpServer.ts src/services/cryptoService.ts

If you want to add a real build pipeline later, the next step would usually be:

1. Add a tsconfig.json
2. Add build, dev, and typecheck scripts to package.json
3. Emit compiled JavaScript into a dist/ directory

Testing

There is not a dedicated automated test suite yet.

Right now, the practical testing flow is:

1. Run the TypeScript check command above
2. Start the server with npx tsx src/server.ts
3. Connect with an MCP client and exercise the registered tools/resources/prompts

Suggested Manual Smoke Tests

• Call ping and confirm it returns pong
• Call add_numbers with two values and confirm the sum
• Call get_price with BTC, ETH, Bitcoin, or Ethereum
• Call get_price_change and confirm a 24-hour summary is returned
• Read the activity_log resource and confirm requests are recorded
• Use the executive_summary prompt and confirm it references the crypto tools correctly

Notes

• The HTTP boilerplate and session handling are intentionally separate from business logic.
• Session state is stored in memory, so this server is best suited for local development or simple demos.
• The crypto tools depend on outbound network access to Binance.
• The activity log is stored locally in activity.log at the project root.

Future Improvements

• Add tsconfig.json
• Add npm scripts for dev, build, typecheck, and test
• Add automated tests for:
  • symbol normalization
  • Binance response handling
  • MCP tool/resource/prompt registration
  • HTTP session lifecycle