Which scheduling tools have an MCP server?

The similarities matter more than the differences. Both map an existing REST API into MCP, which is why the tool counts are close and both land around 35. Both are account-scoped through OAuth: the assistant acts as you, on your data.

That has a consequence worth being explicit about. Anything the assistant can read — booking history, who booked you, what they wrote in an intake form — it can also repeat in a conversation, put in a summary, or hand to another tool. For managing your own scheduling that is exactly the power you want. It is simply a different question from “how do I let a stranger book me safely.”

• Already on one of them — use that one. Neither server is differentiated enough to justify migrating a scheduling setup.
• Self-hosting, data residency or open source matters — Cal.com. Calendly is vendor-hosted only.
• You want the widest integration ecosystem — Calendly, which also has more third-party MCP wrappers if the official tool surface is not enough.
• Team routing, round-robin, payments — both do these well, and are the right category of tool for it.

There is a third approach that does not belong in the comparison above, because it is not trying to do the same job.

Instead of authenticating an assistant into your account, the server computes free/busy internally and exposes only the resulting open slots, with no authentication required to read them and no tool capable of returning a calendar event. That inverts who the integration is for: not your assistant managing your calendar, but somebody else's assistant being able to reach you without either side sharing credentials.

This pattern is not exclusive to any one product, and it would be misleading to imply otherwise: Cal.com's REST API already returns another user's open slots without authentication. The difference is what is exposed to an assistant as a callable tool, and whether anything intersects several people's availability in one step rather than leaving you to do it.

Lucie Sync works this way — we build it, which is why it is in its own section rather than the table. It is not a standalone alternative to Calendly or Cal.com and does not try to be: no team round-robin, no routing forms, no payments, Google Calendar only. It is one of the utilities that come with a Lucie Network membership, built for a narrower problem — founders, investors and operators trying to make time with people at other companies, where the usual booking-link asymmetry (my link, you fit around me) reads wrong between peers and does not extend past two people.

If that is the problem you have, the mechanics are in the connector docs and the reasoning is in agent-to-agent scheduling. If you want an assistant administering your own scheduling account, the two servers above are the better answer and this one will disappoint you.