Connecting a client

Before you start

You need an Inkfree account on any plan, and an AI client that supports remote MCP servers over streamable HTTP with OAuth sign-in. Every client connects to the same address:

https://api.inkfree.app/core/inkfree/mcp/

Keep the trailing slash. Menu names in each client change between versions, so the steps below describe where to look rather than promising exact labels.

How do I connect Claude?

In Claude on the web or the Claude desktop app:

1. Open Settings → Connectors.
2. Choose Add custom connector and name it, for example "Inkfree".
3. Paste the MCP endpoint above as the URL and save.
4. Click Connect. Claude opens the Inkfree sign-in page.
5. Log in with your Inkfree account, review the consent screen, and click Approve.

The connector is then available in new chats.

How do I connect ChatGPT?

ChatGPT supports custom MCP connectors from its settings, on the plans that offer them:

1. Open Settings and go to the Apps (or Connectors) area.
2. Add a custom connector and paste the same MCP endpoint.
3. Sign in to Inkfree when prompted and click Approve.

If you cannot find the option, your ChatGPT plan or workspace settings may not allow custom connectors yet.

Claude Code

Add the server from your terminal:

claude mcp add --transport http inkfree https://api.inkfree.app/core/inkfree/mcp/

Then run /mcp inside Claude Code, choose inkfree, and authenticate. Your browser opens the Inkfree sign-in and consent screens.

VS Code

In VS Code with GitHub Copilot agent mode, add the server to .vscode/mcp.json in your workspace (or to your user MCP configuration):

{
  "servers": {
    "inkfree": {
      "type": "http",
      "url": "https://api.inkfree.app/core/inkfree/mcp/"
    }
  }
}

Start the server from the file or the MCP servers list, then sign in to Inkfree in the browser window that opens.

Other MCP clients

Any client that can add a remote MCP server with OAuth follows the same pattern: add the URL, sign in, approve. The client must support streamable HTTP and OAuth 2.1 with dynamic client registration.

How sign-in works

The Inkfree MCP server is an OAuth 2.1 protected resource. A compliant client handles every step itself:

1. Discovery. An unauthenticated request returns 401 with a WWW-Authenticate: Bearer resource_metadata="…" header. The client reads that protected resource metadata to find the Inkfree authorization server.
2. Registration. The client registers itself through dynamic client registration (RFC 7591) as a public client, so there is no client secret to configure.
3. Authorization. The client opens the authorization code flow with PKCE (S256). You log in to Inkfree and approve the requested scopes on the consent screen.
4. Tokens. Access tokens last one hour. The client refreshes them in the background with a rotating refresh token, so you are not asked to sign in again while you keep using the connector.

The server advertises three scopes: mcp:read, mcp:write, and mcp:send. Tokens act as the user who approved them, with that user's Inkfree role.

Disconnecting

Remove the Inkfree connector or server entry from your AI client's settings. The client stops calling Inkfree immediately, and actions it already took stay in each envelope's audit trail.

Troubleshooting

• The client cannot connect. Check that the URL ends with /mcp/, including the trailing slash.
• The sign-in page belongs to a different product. The URL is wrong. Remove the server and add it again with the exact MCP endpoint above.
• Registration fails with `invalid_redirect_uri`. The client uses a redirect scheme the server does not accept. See the note under Other MCP clients.
• A tool call is refused. Read the error the assistant reports. Common causes are acting on an envelope you do not own (for example, sharing someone else's envelope), deleting a Pending envelope before voiding it, or deleting a folder that is not empty.
• Calls fail with a rate-limit message. Wait for the retry time the error reports, then try again.