Connect an AI assistant
You can connect an AI assistant (Claude by Anthropic; ChatGPT via Developer mode) to your calendars. It then answers questions about your availability — “Am I free Thursday at 2pm?”, “Where do I have two hours in one block this week?” — and, when you ask, creates events too.
Supported today are Claude, Claude Code and ChatGPT – Gemini and Mistral are coming soon. You can also connect automation tools with MCP support: n8n and Zapier have their own guides. For an overview with all benefits, see the product page.
What makes it different: you decide per calendar what the assistant may see and do. Calendars you don’t share simply don’t exist for it.
Video: explained in 8 minutes
Section titled “Video: explained in 8 minutes”The full walkthrough — all three routes (Claude, Claude Code, ChatGPT), granting calendars, the first event from a prompt and the access log:
Clicking play loads YouTube. Data will be sent to Google.
What the assistant can do
Section titled “What the assistant can do”- Read availability — straight from the provider (Google, Outlook, iCloud, GMX, …), not from a copy. You set how much detail it gets per calendar: only whether you’re busy, title and time, or full details. → What the assistant sees
- Find events — “When is my dentist appointment?”, “When was the meeting with Julius?” — searches title, location and description of your events. Only in calendars whose visibility level shows titles; “Busy only” calendars cannot be searched. → What the assistant sees
- Create and manage events (on every plan) — when you ask, it adds events and manages the ones it created itself. Never your existing ones. → Write access
- Send feedback — if something’s missing (“move my existing event”), the assistant can report it to us on your request. If you like, we’ll get back to you once about it.
All tools in technical detail: For developers: tool reference.
What stays in your hands
Section titled “What stays in your hands”- You pick the calendars one by one and set the detail level (and optionally write access) for each.
- You can revoke access at any time — one click on the “AI assistant” page and the access is dead immediately. There’s also a kill switch that revokes every access at once.
- Every query is logged — only that and what was queried, never the content of your events. On Professional you can export the log as CSV.
- Access expires automatically if it goes unused for a long time.
Connect the assistant
Section titled “Connect the assistant”Pick your assistant — every route leads to the same grant:
Connect Claude — via Claude’s connector directory (the simplest route).
Connect Claude Code — in the terminal, via a command.
Connect ChatGPT — via Developer mode (advanced).- Connect n8n — AI agent workflows with calendar access, via key.
- Connect Zapier — calendar tools as regular Zap steps, no AI model needed.
Revoke access
Section titled “Revoke access”You can cut off an assistant’s access yourself at any time — the revoke in Kalender Sync is the authoritative one, regardless of what happens in the assistant itself:
- Individually: under AI assistant, click Revoke on that access. Effective immediately; all of that access’s tokens are dead.
- Kill switch: one click revokes every access at once.
Removing a connector only in the assistant (Claude, ChatGPT) disconnects it there locally — the access at our end stays until you revoke it in Kalender Sync (or until it expires automatically after long disuse).