Connect a client

Every client needs the same two things: the endpoint https://api.infinity.swiss/mcp, and an administrator of the organisation who approves the connection in the browser. There is no client ID or secret to create beforehand — the overview explains how the authorisation works.

Claude
ChatGPT
Cursor
VS Code
Other clients

On claude.ai and in the desktop app, open Customize, then Connectors, press the plus button and choose “Add custom connector”. Enter https://api.infinity.swiss/mcp and connect; Claude sends you to Infinity to sign in and approve. In a Team or Enterprise workspace an owner has to add the connector in the organisation settings first. Leave the OAuth client fields under Advanced settings empty, because Claude registers itself.In Claude Code, add the server and then authenticate:

claude mcp add --transport http infinity https://api.infinity.swiss/mcp

Running /mcp in Claude Code lists the server and offers to authenticate it, which opens the same consent page. Add --scope project to the command to write the server into the repository’s .mcp.json instead of your own configuration.

Adding an MCP server is part of ChatGPT’s developer mode, which you turn on under Settings, Security and login, and which an administrator may have to allow for a workspace first. Then create a new app on the apps page and give it the full URL https://api.infinity.swiss/mcp. ChatGPT runs the sign-in and consent flow, after which you pick which of the Infinity tools the app may use.

Add the server to .cursor/mcp.json in a project, or to ~/.cursor/mcp.json to have it everywhere:

{
  "mcpServers": {
    "infinity": {
      "url": "https://api.infinity.swiss/mcp"
    }
  }
}

The url is what makes the entry a remote server; no further fields are needed, as Cursor registers itself and handles the OAuth flow. Enable and authenticate the server on the Customize page.

Add the server to .vscode/mcp.json in the workspace, or run “MCP: Add Server” from the command palette and pick the HTTP option:

{
  "servers": {
    "infinity": {
      "type": "http",
      "url": "https://api.infinity.swiss/mcp"
    }
  }
}

A browser window opens for the authorisation the first time the server is started. VS Code registers itself, so the oauth block other servers need can be left out.

Any client that speaks Streamable HTTP and OAuth 2.1 works. What it needs to know:

The endpoint https://api.infinity.swiss/mcp
Protected resource metadata at https://api.infinity.swiss/.well-known/oauth-protected-resource/mcp and authorisation server metadata at https://api.infinity.swiss/.well-known/oauth-authorization-server
The authorisation code grant with PKCE (S256), and resource set to https://api.infinity.swiss/mcp
A redirect URI on https, or on http at localhost or 127.0.0.1 with any port. Custom schemes are rejected.
Either a Client ID Metadata Document, which we prefer, or dynamic client registration at https://api.infinity.swiss/oauth/register. Clients are public, so no secret is issued.

To try the server out before wiring it into a client, point the MCP Inspector at it, which walks through the same authorisation flow:

npx @modelcontextprotocol/inspector \
  --server-url https://api.infinity.swiss/mcp --transport http

When a connection does not work

A tool call that needs a scope the connection was not granted fails with an insufficient_scope challenge. Connect the client again and grant the module it asks for; the new approval replaces the existing connection. If consent never appears, check that the person approving is an administrator of the organisation, and that the client’s redirect URI is https or loopback.

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When a connection does not work

​When a connection does not work

When a connection does not work