How to Add an MCP Server to Claude, ChatGPT and Cursor

Quick answer: An MCP server gives an AI assistant tools it can call, such as a calculator or a DNS lookup. To add a remote MCP server to Claude, open Settings, then Connectors, choose Add custom connector and paste the server URL. In Claude Code run claude mcp add --transport http with a name and the URL. Cursor and VS Code take the same URL in a small JSON file. This guide uses the free server at https://irfanaslam.io/mcp, which needs no sign-up or API key.

What an MCP server is

The Model Context Protocol (MCP) is an open standard for connecting AI assistants to outside tools and data. Anthropic published it in late 2024, and Claude, ChatGPT, Cursor, VS Code, Windsurf and many other apps now support it.

An MCP server lists tools, each with a name, a description and the inputs it accepts. Your AI app reads that list when it connects. When a question needs a tool, the model fills in the inputs, the app sends the call to the server, and the answer comes back into the chat. You ask in plain language; the model decides which tool to use.

Servers come in two kinds:

• Local servers run as a program on your computer and talk over standard input and output. They suit tools that need your files.
• Remote servers run on the internet and are reached with a URL over Streamable HTTP. Nothing is installed, and they work in web and mobile apps too.

A remote MCP server is the easiest way to start, because connecting one is just pasting a URL.

The free MCP server used in this guide

The examples use irfanaslam.io/mcp, a free public MCP server I built and run on Cloudflare Workers. It needs no account and no API key, and it stores nothing you send. It has 71 tools in four groups:

Each tool matches a free browser tool on irfanaslam.io, so you can check any answer by hand.

Add an MCP server to Claude (web, desktop and mobile)

1. Open Claude and go to Settings, then Connectors.
2. Choose Add custom connector.
3. Enter a name such as Irfan Aslam Tools and the URL https://irfanaslam.io/mcp. Leave the advanced OAuth fields empty; this server needs no sign-in.
4. Click Add. Claude connects and reads the tool list.
5. In a chat, open the tools menu (the sliders or plus button) and make sure the connector is switched on.

A connector you add on the web also appears in the Claude desktop and mobile apps signed in to the same account. On Team and Enterprise plans an owner may need to allow custom connectors first.

Claude asks before it runs a tool the first time. You can allow it once or always for that tool.

Add an MCP server to Claude Code

Claude Code adds remote servers with one command:

claude mcp add --transport http irfanaslam https://irfanaslam.io/mcp

Add --scope user to make it available in every project, or --scope project to save it in the project's .mcp.json so your team gets it too. Check the connection with:

claude mcp list

Inside a session, /mcp shows each server's status and tools.

Add an MCP server to ChatGPT

ChatGPT supports remote MCP servers as custom connectors on plans that allow them. Open Settings, then Apps & Connectors, then Advanced settings, and turn on Developer mode. Back in Apps & Connectors choose Create, give it a name, paste the server URL and set authentication to No authentication. Then pick the connector from the tools menu in a new chat.

Menu names change often in ChatGPT, so if a step looks different, look for the developer mode or custom connector setting.

Add an MCP server to Cursor and VS Code

Cursor reads servers from ~/.cursor/mcp.json (all projects) or .cursor/mcp.json (one project):

{
  "mcpServers": {
    "irfanaslam": {
      "url": "https://irfanaslam.io/mcp"
    }
  }
}

VS Code with GitHub Copilot reads .vscode/mcp.json in the workspace. You can also run MCP: Add Server from the Command Palette:

{
  "servers": {
    "irfanaslam": {
      "type": "http",
      "url": "https://irfanaslam.io/mcp"
    }
  }
}

Use agent mode in the chat panel, then open the tools picker to see the server's tools.

Cursor works best with fewer tools per server. Instead of the full server, you can add only the groups you need: https://irfanaslam.io/mcp/saudi, https://irfanaslam.io/mcp/hse, https://irfanaslam.io/mcp/dev or https://irfanaslam.io/mcp/web.

Apps that only run local servers

Some older clients only start local servers. The open-source mcp-remote package bridges them to a remote URL. It needs Node.js:

{
  "mcpServers": {
    "irfanaslam": {
      "command": "npx",
      "args": [
        "-y",
        "mcp-remote",
        "https://irfanaslam.io/mcp"
      ]
    }
  }
}

To test a server without any AI app, run the official MCP Inspector with npx @modelcontextprotocol/inspector, choose Streamable HTTP and enter the URL. It lists the tools and lets you call them by hand.

Things to ask once it is connected

• "How much end-of-service award do I get after 6 years on SAR 12,000 if I resign?" (uses the Saudi end-of-service tool, Labor Law Articles 84 and 85)
• "What is my take-home salary on SAR 9,000 basic and SAR 2,250 housing as a Saudi first registered with GOSI in 2025?"
• "Convert 1 Ramadan 1448 to a Gregorian date and give me Riyadh prayer times that day."
• "What is the price of 21 karat gold per gram in Saudi Arabia today, and how much zakat do I owe on SAR 120,000 in savings?"
• "Check the SPF, DKIM and DMARC records of my domain and tell me what to fix."
• "It is 44 °C with 25% humidity. Is heavy outdoor work safe, and what work-rest cycle do we need?" (heat stress tool)
• "Run an SEO check on my homepage and list what to fix."

The model often chains tools on its own: for the zakat question it fetches the live gold price, works out the nisab and then the zakat due.

Is it safe to connect an MCP server?

A connector lets the model send data to the server, so treat it like any website you type into. Before adding one:

• Use servers from people or companies you trust, and read what each tool does.
• Prefer read-only tools. Every tool on this server only reads or calculates; none can change anything.
• Keep tool approval on for servers that can write, send or delete.
• Watch for prompt injection: text a tool returns from the web can contain instructions. Good apps show tool results to you, so read them.

This server is stateless: each request is answered and forgotten, there are no accounts or cookies, and a rate limit of about 60 calls a minute per network keeps it fair. Results are estimates, not legal, religious or financial advice.

Troubleshooting