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Remote MCP Server URL: Add One to Claude, ChatGPT, Cursor

A remote MCP server URL is one https address your AI app connects to. Add it in Claude, ChatGPT, Cursor and Claude Code, with a real test call and fixes.


Published · Updated · 6 min read

Cover image: One URL, no install

A remote MCP server URL is an HTTPS address, like https://api.weirapp.io/mcp, that your AI app connects to instead of running a program locally.

This guide is for anyone adding one to Claude, ChatGPT, Cursor or Claude Code. You get the steps for each app, checked against each vendor's docs in October 2026, and a real test call. Our example is Weir's MCP server, which we run.

In Claude Code, one line adds it:

claude mcp add --transport http weir https://api.weirapp.io/mcp
  1. Copy the URLhttps://api.weirapp.io/mcp, ending in /mcp.
  2. Add it to your appClaude, ChatGPT, Cursor or Claude Code.
  3. Sign inApprove the connection in the browser.
  4. Test itAsk a question that calls a free tool.

What is a remote MCP server URL?

MCP, the Model Context Protocol, lets an AI app call outside tools. The server is the program that holds those tools.

The MCP spec, version 2026-07-28, defines two standard ways to reach a server:

Transport Where it runs What you give the app
stdio (local) Your computer A command, like npx ...
Streamable HTTP Someone's server A URL, like https://.../mcp

With stdio, the app starts the server as a child process on your machine. With Streamable HTTP, each message is an HTTP POST to one URL. That URL is the remote MCP server URL.

A remote URL wins in three ways:

  • Nothing to install. No Node, Python or Docker on your laptop.
  • It follows your account. Claude's web, desktop and phone apps share one connector.
  • Chat apps need it. Claude and ChatGPT run in the cloud, so they can't start a program on your computer.

You may still see URLs ending in /sse. That is the older SSE transport, and Claude Code's docs call it deprecated.

Step 1: Add a remote MCP server URL in Claude

Claude calls these "custom connectors." On Pro and Max, as of October 2026:

  1. Open Customize, then Connectors.
  2. Click + Add, then Add custom connector.
  3. Name it Weir, paste https://api.weirapp.io/mcp, and click Continue.
  4. Keep the sign-in settings Claude detects, then click Add and approve in Weir.

On Team and Enterprise, an owner adds it under Organization settings, Connectors, Add, Custom, Web. Members then click Connect.

Claude's help center says the Free plan allows one custom connector. It also says Claude connects from Anthropic's cloud, so the URL must be public. A server on localhost won't work here. Our Claude integration guide covers the plan differences.

Step 2: Add it in ChatGPT

ChatGPT now creates a custom MCP server as a plugin, on the web:

  1. Go to chatgpt.com/plugins, click +, and choose Add custom MCP server.
  2. Name it, paste the URL as the Server URL, and pick OAuth.
  3. Select I understand and want to continue, then Create as a plugin.
  4. Install the plugin, then type @Weir in a chat.

OpenAI's help center lists full MCP support for Business, Enterprise and Edu. Pro accounts can connect servers with read and fetch tools only. See our ChatGPT integration guide for the full walk-through.

Step 3: Add it in Cursor

Cursor reads servers from ~/.cursor/mcp.json, or .cursor/mcp.json for one project. A remote server takes url where a local one takes command:

{
  "mcpServers": {
    "weir": { "url": "https://api.weirapp.io/mcp" }
  }
}

Cursor asks you to sign in the first time it connects. Cursor's docs also accept a headers block. With Weir, Cursor ignores a key there while the server offers sign-in. The Cursor guide walks through it.

Step 4: Add it in Claude Code

The --transport http flag marks the URL as remote. Then run /mcp inside Claude Code and pick Weir to sign in.

For CI, claude -p or any machine with no browser, send a key instead:

claude mcp add --transport http weir https://api.weirapp.io/mcp \
  --header "Authorization: Bearer $WEIR_API_KEY"

Add --scope user to use the server in every project. Claude Code's docs list three scopes: local by default, project and user.

If you sign in to Claude Code with the same Claude account, connectors from Step 1 show up there too.

Step 5: Test the connection with a real call

Start with a free tool, so a wrong setup costs nothing. Paste this into any of the four apps:

What's my Weir usage?

The app should call get_usage. We ran it on 26 October 2026 and got this back, trimmed:

{
  "data": { "balance": 8630, "tier": "free", "spendingPaused": false },
  "meta": { "creditsCharged": 0 }
}

Then try a paid call. We asked for @AnthropicAI's top 3 posts about MCP:

Search X for posts from @AnthropicAI about MCP, top 3.

It cost 4 credits: 1 for the call and 1 per post. The third post is the one that matters here:

{
  "text": "Claude Code can now connect to remote MCP servers. ...",
  "url": "https://x.com/AnthropicAI/status/1935367951542280239",
  "createdAt": "2025-06-18T16:04:11.000Z",
  "likeCount": 2561
}

Here is what the two test calls cost:

0credits for get_usage, the free check
4credits for a 3-post search
5,000free credits every month, no card

A 10-post search costs 11 credits, so the free credits cover about 450 of them.

If the remote MCP server won't connect

  • The app says it can't reach the server. Claude and ChatGPT connect from the cloud, so a private or localhost URL fails. Use a public https:// URL.
  • You put the URL in claude_desktop_config.json. That file is for local servers. Use the Connectors screen.
  • You get a 401 with no sign-in prompt. Weir answers a missing key with a 401 and a sign-in challenge. Send Authorization: Bearer <key> or sign in.
  • A tool returns 402. The account is out of credits. Retrying won't help; a person has to add credits.
  • Cline or n8n errors. Set the transport to Streamable HTTP, not SSE.

We sent a request with no key on 26 October 2026. Weir answered 401 with a header that points the app to its sign-in details:

HTTP/1.1 401 Unauthorized
Www-Authenticate: Bearer resource_metadata="https://api.weirapp.io/.well-known/oauth-protected-resource/mcp"

That header is how Claude, ChatGPT and Cursor know to open a sign-in page.

When not to use Weir

  • You need to post on X. Weir is read-only. X's own API can write.
  • You want a server that runs offline. A remote URL needs the internet.
  • You need tools for your own app's data. Build your own server; Weir only reads public Reddit and X data.

FAQ

What is a remote MCP server URL?

It is an HTTPS address, usually ending in /mcp, where an MCP server listens over the Streamable HTTP transport. You paste it into an AI app instead of installing a local program. Weir's is https://api.weirapp.io/mcp.

What is the difference between a local and a remote MCP server?

A local server runs on your computer as a process the app starts, over stdio. A remote server runs somewhere else and the app reaches it by URL. Chat apps like Claude and ChatGPT can only use remote ones.

Can Claude Desktop use a remote MCP server?

Yes, through Customize and Connectors, not the config file. claude_desktop_config.json only starts local servers. The connector then works in Claude on the web, desktop and phone.

Does a remote MCP server need an API key?

Not always. Most chat apps and coding agents sign in with OAuth in a browser. A key in an Authorization header is for scripts, CI and frameworks with no browser.

Sources

All checked on 26 October 2026:

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