MustDo MCP server

mustdo-mcp

日本語版はこちら (README.ja.md)

MCP server for MustDo — the iOS To-Do alarm that keeps ringing until you do it.

It lets Claude (Claude Code, Claude Desktop, claude.ai, the Claude iPhone app) and any other Model Context Protocol client read and write your MustDo To-Dos.

CloudKit private database of your Apple ID (container iCloud.jp.lightning.mustdo, zone MustDo). This server talks to Apple's CloudKit Web Services and reads/writes the same records as the iPhone app.

• Your data stays in your iCloud. MustDo has no database of its own for To-Dos. They live in the

hosted relay (see below) keeps To-Do content on Lightning LLC servers.

• The developer never stores your To-Dos. Neither the local server in this repository nor the

• After a write, CloudKit pushes a silent notification to your iPhone, so the app updates right away.

Two ways to use it

A. Hosted relay — https://ltng.jp/api/mustdo/mcp

Sign in with the same Apple ID you use in the MustDo app.

1. claude.ai → Settings → Connectors → Add custom connector → URL https://ltng.jp/api/mustdo/mcp (name it "MustDo").
2. Click Connect. You will see a consent page on ltng.jp explaining what is stored, then Apple's sign-in page.

1. Done. The same connector is available in the Claude iPhone app.

What the relay keeps, honestly:

encrypted with AWS KMS (AWS Tokyo region) so it can call CloudKit on your behalf on each request.

• When you sign in, Apple issues a CloudKit sign-in token (ckWebAuthToken). The relay stores this token

After confirming with your Apple ID, the stored token is deleted immediately. It is also deleted automatically when Apple invalidates the sign-in (the tools then return RECONNECT_REQUIRED; just reconnect).

• It also stores hashed OAuth access/refresh tokens for the connector itself.
• It does not store or log your To-Do content, your Apple ID email, your password, or your raw iCloud user ID.
• Disconnect: remove the connector in claude.ai and visit .

Full write-up: .

B. Run locally (stdio)

Requirements:

• macOS with Node.js 24 or newer
• The MustDo app installed and synced to iCloud at least once (the app creates the zone and the Account record)
• A CloudKit API Token for the MustDo container. It is not currently distributed to the public — see "About the CloudKit API Token" below. Without it, use the hosted relay (A)

git clone https://github.com/lightning-llc-jpn/mustdo-mcp mustdo-mcp
cd mustdo-mcp
npm install
npm run build        # -> dist/index.js
npm test             # vitest; CloudKit is mocked

Register with Claude Code:

claude mcp add mustdo \
  -e MUSTDO_CK_API_TOKEN=<MUSTDO_CK_API_TOKEN> \
  -e MUSTDO_CK_ENV=production \
  -- node /path/to/mustdo-mcp/dist/index.js

Or put the settings in ~/.mustdo/config.json and register without -e:

{
  "apiToken": "<MUSTDO_CK_API_TOKEN>",
  "environment": "production"
}

Then ask Claude to run the sign_in tool once. The server opens Apple's sign-in page in your browser, listens on http://localhost:51234/callback, and saves the returned token to ~/.mustdo/auth.json (mode 0600).

Shortened. The full README is on GitHub.