Quickstart Resources

A repository of servers and clients from the following Model Context Protocol tutorials:
- Quickstart – a simple MCP weather server
- Building MCP clients – an LLM-powered chatbot MCP client

Extended Features

This repository has been enhanced with additional implementations:

Integration Methods

| Method | For Custom GPTs? | For CLI/Dev Use? |
|----------------------|:----------------:|:----------------:|
| index.ts (Claude) | ❌ | ✅ |
| index-openai.ts | ❌ | ✅ |
| http-bridge.ts | ✅ | ✅ |

- Claude Integration (index.ts): Original CLI client using Anthropic's Claude
- OpenAI Integration (index-openai.ts): Alternative CLI client using OpenAI GPT models (not for custom GPTs)
- HTTP API Bridge (http-bridge.ts): REST API server for connecting custom GPTs via Actions (recommended for GPT Builder)

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Custom GPT Integration

The HTTP API bridge is the only supported method for connecting custom GPTs in OpenAI's GPT Builder:

- REST API server for custom GPT Actions
- File: http-bridge.ts
- Web-based integration via OpenAPI schema
- Endpoints: /weather/forecast, /weather/alerts

How to Connect Your Custom GPT to Your MCP Server

Step 1: Start Your Servers

1. Start the MCP Weather Server

   cd weather-server-typescript

   npm run build

   node build/index.js

   

2. Start the HTTP Bridge

   cd mcp-client-typescript

   npm run build-bridge

   node build/http-bridge.js ../weather-server-typescript/build/index.js

   

Step 2: Expose Your Local Server to the Internet

OpenAI requires a public HTTPS endpoint for Actions. The easiest way is to use ngrok:

ngrok http 3000

- This will give you a public HTTPS URL like https://randomstring.ngrok.io.

Step 3: Prepare Your OpenAPI Schema

- Download or copy your OpenAPI schema from http://localhost:3000/openapi.json.
- Update the "servers" section to use your ngrok URL:

  "servers": [

    { "url": "https://randomstring.ngrok.io" }

  ]

  

- Add a privacy policy and terms of service to the "info" section:

  "info": {

    "title": "Weather API",

    "description": "Weather forecasts and alerts via MCP",

    "version": "1.0.0",

    "termsOfService": "https://www.example.com/terms",

    "x-privacy-policy-url": "https://www.example.com/privacy"

  }

  

- You can use placeholder URLs or your own.

Step 4: Configure Your Custom GPT in GPT Builder

1. Go to ChatGPT GPT Builder
2. Click the Actions tab.
3. Import the schema from your ngrok URL (e.g., https://randomstring.ngrok.io/openapi.json) or paste the edited JSON.
4. Set Authentication to "None".
5. Save and publish your GPT.

Step 5: Test Your Custom GPT

Ask your GPT:
- "What's the weather forecast for San Francisco?"
- "Are there any weather alerts in California?"
- "Get me the forecast for latitude 40.7, longitude -74.0"

Your GPT will call your HTTP bridge, which will call your MCP server and return real weather data!

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Using the HTTP Bridge with Remote or Third-Party MCP Servers

By default, the HTTP bridge is designed to launch and connect to a local MCP server (e.g., your weather server). However, you can also use it to connect to any MCP server that is accessible from your machine, including:

- A remote MCP server running on another machine or in the cloud
- A third-party MCP-compatible service
- A Dockerized MCP server with a mapped port

How to Connect the HTTP Bridge to a Remote MCP Server:

1. Ensure the remote MCP server is running and accessible
- The server must be reachable from the machine running the HTTP bridge (e.g., via public IP, VPN, or SSH tunnel).
- The server should support the same MCP stdio or TCP transport.

2. Modify the HTTP bridge launch command
Instead of launching a local script, you can point the bridge to a remote server by:
- Using an SSH command to start the server remotely and pipe stdio over SSH
- (Or, for advanced users) Modifying the bridge to use a TCP transport if the MCP server exposes a TCP socket

Example: Using SSH to connect to a remote MCP server

   node build/http-bridge.js "ssh user@remotehost 'node /path/to/remote/build/index.js'"

   

- This will use SSH to start the MCP server on the remote host and connect the stdio streams to your bridge.

3. (Optional) Use TCP Transport for Direct Network Connections
- If your MCP server supports TCP, you can modify the bridge to use TcpClientTransport instead of StdioClientTransport and provide the remote host/port.

Example (pseudo-code):

   import { TcpClientTransport } from '@modelcontextprotocol/sdk/client/tcp.js';

   // ...

   this.transport = new TcpClientTransport({ host: 'remotehost', port: 12345 });

   

4. Continue with the rest of the setup
- Expose your HTTP bridge with ngrok or deploy it to a public server as before.
- Your custom GPT will now be able to access any MCP server you can reach!

Tip:
This flexibility means you can use the HTTP bridge as a universal adapter for any MCP-compatible tool, whether it's running locally, in the cloud, or provided by a third party.

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Troubleshooting & Tips

- Public URL Required: OpenAI will not accept localhost or http:// URLs for public GPTs. Always use your ngrok HTTPS URL.
- Privacy Policy: A valid privacy policy URL is required for public GPTs. Use a placeholder or generate one at privacypolicies.com.
- Schema Import Issues: If importing from URL fails, copy the JSON and paste it manually.
- ngrok Free Plan: The URL changes each time you restart ngrok. Update your schema and GPT config if you restart ngrok.
- Production: For a permanent solution, deploy your bridge to a public HTTPS server and use your real domain.

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Architecture Overview

Custom GPT ──Actions──> HTTP Bridge ──MCP──> Weather Server ──API──> National Weather Service

Quick Demo

1. Start weather server: cd weather-server-typescript && npm run build && node build/index.js 2. Start HTTP bridge: cd mcp-client-typescript && npm run build-bridge && node build/http-bridge.js ../weather-server-typescript/build/index.js 3. Create custom GPT with Actions pointing to your ngrok URL (see above) 4. Ask: "What's the weather in San Francisco?"

See mcp-client-typescript/README.md for detailed setup instructions.