MCP Simple Server

A simple server implementing the Model Context Protocol (MCP).

Setup

1. Install dependencies:

npm install

2. Start the server:

npm start

The server will run on http://localhost:3001 by default.

Using the Stdio Server

This project includes a stdio-based implementation of the MCP server that communicates via standard input/output instead of HTTP/SSE.

Running the Stdio Server

npm run stdio

The stdio server accepts JSON-RPC messages via stdin and responds via stdout. All logs are sent to stderr to avoid interfering with the JSON-RPC messages.

Using the MCP Inspector

If you want to use the MCP Inspector with the stdio server, we've created a bridge that connects the HTTP-based inspector to our stdio server:

npm run bridge

This will:
1. Start the stdio server as a child process
2. Create an HTTP server on port 3001
3. Forward JSON-RPC requests from HTTP to the stdio server
4. Return responses back to the HTTP clients

You can then connect the MCP Inspector to http://localhost:3001 and it will work with the stdio server.

Using the Interactive CLI

An interactive command-line interface is provided for easy interaction with the stdio server:

npm run cli

This will start an interactive shell where you can enter search queries:

MCP CLI - Interactive interface to the MCP server
Type "exit" or press Ctrl+C to quit
Examples:
  documents/javascript - Search for documents with keyword "javascript"
  help - Show this help message
--------------------------------------------------
> 

You can enter simple keywords or full document URIs to search.

Using the Sample Client

A sample client is included to demonstrate how to communicate with the stdio server programmatically:

npm run client <query>

For example:

npm run client javascript

This will:
1. Start the stdio server as a child process
2. Send a query for documents matching "javascript"
3. Display the results and exit

Communicating Directly with the Stdio Server

You can also communicate directly with the stdio server by piping JSON-RPC messages:

echo '{"jsonrpc":"2.0","id":"1","method":"mcp.uri","params":{"uri":"documents/sample"}}' | node stdio-server.mjs

Custom Domain Setup

You can access the server via a custom domain by mapping it in your hosts file.

Automatic Setup

Run the included setup script with sudo permissions:

sudo ./hosts-setup.sh

This will add mcp.local to your hosts file pointing to 127.0.0.1 and flush your DNS cache.

Manual Setup

1. Edit your hosts file:
- On macOS/Linux: /etc/hosts
- On Windows: C:\Windows\System32\drivers\etc\hosts

2. Add the following line:

127.0.0.1 mcp.local

3. Flush your DNS cache:
- On macOS: sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder
- On Windows: ipconfig /flushdns
- On Linux: Depends on your distribution

4. Access the server at http://mcp.local:3001

Environment Variables

You can customize the server by setting the following environment variables:

- PORT: The port to run the server on (default: 3001)
- DOMAIN_NAME: The custom domain name (default: mcp.local)
- SERVER_IP: The IP address to bind to (default: 127.0.0.1)

Example:

PORT=8080 DOMAIN_NAME=myapi.local npm start