Leash

Inspiration

Connect an AI agent to your Mac and macOS asks one question: may "node" control Calendar? One Allow, and every Node program can read your calendar, mail and messages. We wanted consent shaped like the task: this calendar, these fields, for one hour.

What it does

Leash sits between the agent and Calendar, Reminders, Mail and Messages.

• Grants scoped to named calendars, mailboxes and lists, specific fields, and an expiry. Create them from your real accounts in the viewer.
• Filtering: the model only sees what a grant covers. Private notes and personal calendars never reach it.
• The agent must say why. Anything outside a grant raises a dialog showing its reason. Deny is the default.
• Touch ID for every send, even inside a grant.
• A hash-chained ledger of every call, with a live viewer, countdowns and Revoke.

In the demo, a prompt-injected email tells the agent to text everyone a link. Leash stops it, shows the agent's reason, and logs the denial.

How we built it

Node.js MCP server, fixed JXA scripts (no agent-written code runs), a Swift Touch ID helper, and a local web viewer.

What's next

The agent in its own macOS VM with its own Apple Account (the VM already boots), approvals on your iPhone, and a signed Leash app.

Built With

• applescript
• claude
• claude-desktop
• javascript
• jxa
• localauthentication
• macos
• model-context-protocol
• node.js
• swift
• touch-id
• zod