Fax from Claude and Other AI Assistants

The connector URL

FaxUp works with any assistant that supports remote MCP servers. There is no sign-up and no API key:

https://mcp.faxup.net/mcp

Claude

Claude on the web, desktop and mobile

1. Open Claude, then Settings and Connectors.
2. Choose Add custom connector.
3. Name it FaxUp, paste https://mcp.faxup.net/mcp as the URL, and add it. Leave the advanced (OAuth) settings empty.
4. In a chat, attach or link your PDF and ask Claude to fax it.

On a Team or Enterprise plan, an owner may need to add the connector for the organisation first.

Claude Desktop config file

If you prefer the config file, add this to claude_desktop_config.json (Settings, Developer, Edit Config) and restart Claude. It needs Node.js.

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

Claude Code

claude mcp add --transport http faxup https://mcp.faxup.net/mcp

Cursor

Add FaxUp to Cursor with one click, or put this in ~/.cursor/mcp.json:

{
  "mcpServers": {
    "faxup": { "url": "https://mcp.faxup.net/mcp" }
  }
}

ChatGPT (Developer Mode)

FaxUp is not in the ChatGPT app directory. On plans that offer Developer Mode, turn it on under Settings, Apps, Advanced settings, then create a connector with the URL above and no authentication.

Other assistants

VS Code, Windsurf, Zed and other MCP clients: add a remote (Streamable HTTP) server with the URL above. Clients that only run local servers can use npx -y mcp-remote https://mcp.faxup.net/mcp.

How it stays safe: you confirm and pay

1. The assistant prepares the fax. FaxUp checks that the number is a fax line in a country it serves (mobile and premium-rate numbers are refused) and that the file is a readable PDF, then returns a link. Nothing is sent and nothing is charged.
2. You check it.The link shows every page, the full number and the price, and asks whether you asked for this fax. If you didn't, cancel it and the file is deleted.
3. You send it on faxup.net. The fax opens in the normal send page, where you see it again, pay $2.99 through Stripe (or use your credits or FaxUp Unlimited) and press Send.

The connector holds no FaxUp, payment or carrier credentials, so no assistant, and no document that tries to trick one, can send a fax by itself. Always check the number on the confirm page: a fax to the wrong number can't be called back.

What the assistant can do

• send_fax: prepare a fax of a PDF, with an optional cover page, and get the confirm link.
• get_fax_status: see whether you opened, cancelled or sent it.
• get_price_quote: what a fax costs, and whether a number can be faxed.
• list_supported_countries: the 62 countries FaxUp reaches.

Questions or a problem with the connector: [email protected].