# Multi Calendar

Your Outlook.com, Microsoft 365, Google, iCloud and other calendars, in one connector.

Free time across all of them, events, booking pages, circles and group polls.

[Add to Claude](https://claude.ai/directory/connectors/lumman-multi-calendar)

Free for every calendar you connect. Any number of booking pages and circles for $50 a year or $5 a month.

- Works with: Claude, ChatGPT, Claude Code and Cursor (and other AI apps)
- Calendars: Any number ([Outlook.com](https://lumman.co/mcp/multi-calendar/outlook), [Microsoft 365](https://lumman.co/mcp/multi-calendar/microsoft-365), [Google](https://lumman.co/mcp/multi-calendar/google), [iCloud](https://lumman.co/mcp/multi-calendar/icloud), [Yahoo](https://lumman.co/mcp/multi-calendar/yahoo), [AOL](https://lumman.co/mcp/multi-calendar/aol), [CalDAV](https://lumman.co/mcp/multi-calendar/other))
- Free: Every calendar (1 booking page, 1 circle)
- Plan: Any number (of booking pages and circles)
- Publisher: Lumman Ltd (Verified by Microsoft)
- Tools: 21 (within 3 permissions, each ticked per calendar account)

## Your calendars

- Each calendar account has its own permissions - you tick what your AI app may do in it.
- The words of every event are screened for prompt attacks before they reach your AI app, and the words of everything it writes before they reach your calendar's provider.
- We keep no copy of your calendars. Events are read from Microsoft, Google, Apple or the calendar's own server each time they are needed. [Privacy Policy](https://lumman.co/privacy)
- Made by Lumman Ltd, a publisher verified by Microsoft.
- A circle sees only its members' busy times - never what their events say.
- Guests book on your own booking page, with no account of their own.

## Your AI app

- [Claude](https://lumman.co/mcp/claude) - From Claude's connectors directory
- [ChatGPT](https://lumman.co/mcp/chatgpt) - As a custom MCP server
- [Claude Code](https://lumman.co/mcp/claude-code) - As a plugin, in two commands
- [Cursor](https://lumman.co/mcp/cursor) - In ~/.cursor/mcp.json

## One request, as it runs

You ask: “When are Tom and I both free for an hour next week? Book the first one.”

1. Finds the circle you share with Tom (`circles_list`)
2. Reads busy time across your 3 calendars and Tom's, and finds Tue 14:00, Wed 10:00 and Thu 16:30 (`circles_free_times_find`)
3. Books Tuesday 14:00 and invites Tom (`events_create`)

## Adding it

1. Add to Claude: Press Add to Claude here. Claude opens a small window on this site.
2. Sign in and add your calendars: Sign in to Lumman with Google, Microsoft, a passkey or an emailed code. Outlook.com and Microsoft 365 calendars connect with Microsoft, Google calendars with Google, iCloud calendars with an app-specific password made at Apple, and Yahoo, AOL, Fastmail, Zoho, GMX and other CalDAV calendars with their address and a password, their server sending their meetings' invitations and answers where it does.
3. Ask: Claude finds free time, books and answers invitations, within the permission each calendar account has.

## Price

- Free: Every calendar. 1 booking page and 1 circle. No card.
- Plan: Any number of booking pages and circles. $50 a year or $5 a month. Switch from monthly to yearly at any time. Cancel any time - the paid period runs to its end.

## Tools

- List calendars (`calendars_list`)
- Read events (`events_list`)
- Read an event (`events_get`)
- Find a time (`free_times_find`)
- Create an event (`events_create`)
- Change an event (`events_edit`)
- Cancel an event (`events_cancel`)
- Answer an invitation (`events_respond`)
- Read scheduling preferences (`preferences_get`)
- Change scheduling preferences (`preferences_set`)
- Show busy time everywhere (`busy_everywhere_set`)
- Make a booking link (`booking_links_create`)
- Set up a booking page (`booking_page_set`)
- Make a group poll (`polls_create`)
- Read a poll's answers (`polls_results`)
- Book a poll's time (`polls_book`)
- List open links and polls (`links_polls_list`)
- Close a link or poll (`links_polls_close`)
- Invite people into a circle (`circles_invite`)
- List circles (`circles_list`)
- Find a time for a circle (`circles_free_times_find`)

## Connect

Address for your AI client: https://books.lumman.co/mcp/calendar

### ChatGPT

1. Plugins > + > Add custom MCP server.
2. Name it, paste the address, choose OAuth, tick the box, press Create as a plugin.
3. Install it, sign in and approve, then @-mention it in a chat.

## If something fails

- The sign-in window ran out or closed: Close it and connect again from your AI client - that opens a fresh request. Any calendar you added stays in your account.
- No calendar is connected yet: Open https://lumman.co/mcp/account/multi-calendar, signed in with the account you approved your AI client with, and add an Outlook, Google, iCloud or other calendar. Then ask again.
- A calendar account stopped working: Microsoft or Google no longer accepts the access it gave, as when the approval is withdrawn there, or Apple no longer accepts its app-specific password, as when it is deleted or the Apple Account password changes, or a CalDAV server no longer accepts its password, as when it is deleted or changed there. Open your account, press Reconnect on that account and ask again.
- The day's actions are used: Multi Calendar takes up to 1,000 actions in any 24 hours, and the answer names the time the next one is available.