Cal.com documentation

What it does

Open-source scheduling infrastructure - booking pages, event types, and a scheduling API/platform - offered both as a free, self-hostable open-source product and as hosted SaaS.

Access and connection

MCP support: official

Access requirements: free - Cal.com's Free plan has "no usage limits" and includes 100+ app integrations; API-key generation is a self-serve account setting in documentation found, not gated behind a paid tier. Cal.com is also open-source and self-hostable via Docker - a genuinely free path Calendly does not offer. Caveat: "Custom APIs" / "Additional APIs" language appears in the Teams ($12/user/mo) and Organizations ($28/user/mo) plan marketing copy, suggesting some advanced API surface (Platform/Orgs-prefixed endpoints) is tier-gated even though basic API-key access is not.

Authentication: Two paths. Hosted server (mcp.cal.com) uses OAuth 2.1 - "your client handles the authorization flow automatically," no API key needed. Self-hosted/local server uses a Cal.com API key generated at Settings -> Developer -> API Keys, passed via a CAL_API_KEY environment variable, run over stdio with Node.js (npx @calcom/cal-mcp@latest).

Research checked: 2026-08-24

These details come from the catalog research. Check the vendor sources below for current setup instructions. They do not establish that a connection or tool call was tested.