Microsoft 365
Work and school calendars on Microsoft 365 connect to Multi Calendar with Microsoft sign-in, once your organisation allows it.
For calendars Microsoft hosts in Exchange Online - not your organisation's own Exchange server.
Add it to
- 1Add to ClaudeOpens claude.ai - press Connect there.
- 2
Sign in, choose Outlook.com or Microsoft 365 and allow access at Microsoft in the window Claude opens. That adds your calendar and approves Claude in one step.
- 3
Ask Claude about your week
- 1
Run in Claude Code
/plugin marketplace add lumman-lab/multi-calendar/plugin install multi-calendar@multi-calendarRun the first, then the second.
- 2
Sign in, choose Outlook.com or Microsoft 365 and allow access at Microsoft on the Lumman page your browser opens. That adds your calendar and approves Claude Code in one step. If none opens, run /mcp and choose multi-calendar.
- 3
Ask, or run
/multi-calendar:week
Needs ChatGPT Pro, Business, Enterprise or Edu. Plus and Free cannot add it.
- 1
Copy the address
- 2Open ChatGPT plugins
Press +, choose Add custom MCP server, name it Multi Calendar, paste the address, choose OAuth, tick the box and press Create as a plugin.
- 3
Install it, then sign in, choose Outlook.com or Microsoft 365 and allow access at Microsoft on the Lumman page it opens. That adds your calendar and approves ChatGPT in one step. In a chat, type @ and choose Multi Calendar.
- 1
Add to
~/.cursor/mcp.json - 2
Sign in, choose Outlook.com or Microsoft 365 and allow access at Microsoft on the Lumman page Cursor opens. That adds your calendar and approves Cursor in one step.
Streamable HTTP, OAuth 2.1 with dynamic client registration. No key or client id.
- VS Code
Run MCP: Add Server, choose HTTP, paste the address and name it multi-calendar.
- Gemini CLI
gemini extensions install https://github.com/lumman-lab/multi-calendarIts first call opens Lumman's sign-in; /mcp auth multi-calendar opens it again.
- Antigravity
agy plugin install https://github.com/lumman-lab/multi-calendarRun /mcp, open multi-calendar_multi-calendar and choose Authenticate; approve on the Lumman page, then paste the code Antigravity shows back into it.
Free for every calendar you have. Any number of booking pages and circles for $50 a year or $5 a month.
Limits
- If Microsoft says your organisation has to approve Lumman first, Lumman shows the address where your administrator approves it. Once they have, connect the calendar again.
- An event can show you as out of office, but Outlook makes no focus time.
Connection
- Reached through
- Microsoft Graph
- Permissions
- Calendars.ReadWrite, User.Read, offline_access - delegated
Your data
- Stored
- Microsoft's credential, encrypted under a key held outside the database
- Calendars
- No copy kept - read from the calendar on each call
- Removing it
- Disconnecting deletes our credential.
Tools
- Offered
- All 21
Everything else
Multi Calendar's address, sign-in, limits and every tool: Multi Calendar's technical details.