Connect Yahoo Calendar to Claude and ChatGPT
Multi Calendar connects Yahoo calendars to Claude and ChatGPT with an app password, never your Yahoo password.
For yahoo.com, ymail.com and rocketmail.com accounts, and those at other domains whose mail Yahoo Mail's own servers receive.
The AI apps' own connectors
Multi Calendar's other provider pages name what the AI apps' own connectors do for their providers: Outlook.com and Hotmail, Microsoft 365, Google Calendar, iCloud, Another calendar.
Connect it
At YahooYahoo makes an app password only in a browser you have signed in to Yahoo with for several days in a row - never in a private window.
The link opens Yahoo in a new tab.
- 1
Sign in to your Yahoo Account Security page at login.yahoo.com.
- 2
Under External connections, choose Create app password.
- 3
Name it Lumman, choose Generate password and copy it.
Yahoo shows it once - leave that page open until Lumman asks for it.
Add it to
- 4Add to ClaudeOpens claude.ai - press Connect there.
- 5
Sign in, add your Yahoo calendar and approve Claude in the window Claude opens - choose Yahoo, AOL, Fastmail, Zoho, GMX or another, type the address and paste the app password when it asks
- 6
Ask Claude about your week
- 4
Run in Claude Code
/plugin marketplace add lumman-lab/multi-calendar/plugin install multi-calendar@multi-calendarRun the first, then the second.
- 5
Sign in, add your Yahoo calendar and approve Claude Code on the Lumman page your browser opens - choose Yahoo, AOL, Fastmail, Zoho, GMX or another, type the address and paste the app password when it asks. If none opens, run /mcp and choose multi-calendar.
- 6
Ask, or run
/multi-calendar:week
Works fully on ChatGPT Business, Enterprise and Edu.
- 4
Copy the address
- 5Open 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.
- 6
Install it, then sign in, add your Yahoo calendar and approve on the Lumman page it opens - choose Yahoo, AOL, Fastmail, Zoho, GMX or another, type the address and paste the app password when it asks. In a chat, type @ and choose Multi Calendar.
- 4
Add to
~/.cursor/mcp.json - 5
Sign in, add your Yahoo calendar and approve Cursor on the Lumman page Cursor opens - choose Yahoo, AOL, Fastmail, Zoho, GMX or another, type the address and paste the app password when it asks
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 connect. Any number of booking pages and circles for $50 a year or $5 a month.
Reach and limits
- Find free time across it and every other calendar you add.
- Create, move and cancel events.
- Share booking links and a booking page, run group polls, and find a time with the people in a circle.
- A meeting with guests is made only where its server says it sends the invitations, updates and cancellations itself, from your own address.
- An invitation is answered here only where its server sends the answer - otherwise answer it from its letter or in the calendar's own app.
- Its calendars receive bookings only where its server sends invitations.
- An event keeps no privacy, out of office, focus time or video link, and shows only as busy or free.
If it refuses
- caldav.calendar.yahoo.com refused this password. Check the username and the password.
- Multi Calendar does not connect AT&T or Verizon.net calendars, nor those of a company whose mail Yahoo keeps, such as Rogers. Nothing was sent.
Connection
- Calendar server
- caldav.calendar.yahoo.com
- Login
- Your whole address and the app password
- Check
- Yahoo's calendar server accepts the password before the account is added
Your data
- Stored
- The app password, encrypted under a key held outside the database
- Calendars
- No copy kept - read from the calendar on each call
- Removing it
- Disconnecting deletes our copy of the password, which works until you delete it on your Yahoo Account Security page under External connections.
Tools
- Offered
- All 21 - events_respond answers only where its server sends answers, and events_cancel cancels only an event the account organises
Everything else
Multi Calendar's address, sign-in, limits and every tool: Multi Calendar's technical details.