Scheduling & Booking · Integration
Cal.com
Add Cal.com to your product for your customers, and give your AI agents governed access to it.
Cal.com is open source scheduling, and the openness is not a footnote here: a customer may be on the hosted service or running their own instance on their own domain, so a connection has to know where it is pointing as well as who it is acting as. Beyond that the model is clean. An event type defines what can be booked, how long it lasts and the questions a booker answers, availability is computed from the connected calendars and the schedules attached to that event type, and a booking is created, moved or cancelled against it. Round robin and collective event types spread bookings across a team, which means the person who ends up on the call is decided by rules the customer set and not by your product picking somebody. Booking created, rescheduled and cancelled events are delivered as they happen. fastn keeps each account's credentials per tenant.
In your product
Embedded for your customers. Per-tenant auth, no per-customer code, maintained by fastn.
Let each customer connect their own Cal.com account, hosted or self-run, so bookings land on the calendar they already keep.
Read live availability for an event type before your product offers a time, rather than storing a slot that has since gone.
Create, reschedule and cancel bookings from inside your product, including the answers a booker gave.
React to booking created, rescheduled and cancelled events so downstream work starts without polling for it.
For your AI agents
Governed, audited access for the agents you build, through the MCP server.
An agent finds a mutually free slot and books it against the right event type, with the booking attributed.
An agent reschedules a meeting on request and confirms what the attendees were told.
An agent reports which bookings were cancelled this week and what reasons were given.
Example prompt
Book a 30 minute intro call with this customer at the first slot both of us have free next week.
Set up Cal.com in 4 steps
- 01Enable the Cal.com connector in your fastn dashboard.
- 02Have each customer authorise their own account, and record the instance URL where they self-host.
- 03Choose the event types your product books against and map the booking questions you collect.
- 04Call it from your product and expose the same governed connection to your agents.
Why teams use the Cal.com integration
What you get by embedding it with fastn instead of building it yourself.
- Ship a Cal.com integration without building it. Your customers connect their own Cal.com account inside your product and work their bookings, events and availability there, with no per-customer code on your side.
- Handle the part that actually costs time: availability is only true at the moment you read it, so a stale free/busy picture becomes a double booking somebody has to apologise for. fastn owns the auth, token refresh, rate limits, pagination and breaking-change fixes, so a Cal.com update is not your on-call problem.
- One integration serves your product and your agents. The same governed Cal.com connection powers in-product features and gives AI agents scoped, audited access, so you let people book and reschedule without leaving your product without wiring it twice.
Used by these teams
Compare with
Calendly
TidyCal
Google CalendarOften used alongside
Tools the same teams tend to run next to Cal.com, across other categories.
Slack
Microsoft Teams
Twilio
AircallCal.com integration FAQ
How do I add a Cal.com integration to my product?
Enable the Cal.com connector in your fastn dashboard, then let each customer authenticate their own Cal.com account. fastn handles the OAuth flow, token storage and refresh per tenant, so there is no Cal.com client code in your app and no per-customer branch in your codebase. Setup is 4 steps.
Do my customers each connect their own Cal.com account?
Yes. Every connection is scoped to the individual customer, so each authorises their own Cal.com account and only ever sees their own bookings, events and availability. That per-tenant isolation is the point of an embedded integration: you support the long tail of customer setups without maintaining an integration per customer.
Can AI agents use this Cal.com integration?
Yes. The same connection is exposed to your agents through the fastn MCP gateway, with permissions scoped per tenant and every call audited. An agent finds a mutually free slot and books it against the right event type, with the booking attributed.
Who maintains the Cal.com integration?
fastn does. When Cal.com changes an endpoint, deprecates a field or alters its auth, the fix lands in the connector rather than in your backlog, and your customers' connections keep working.
Can my product create, reschedule or cancel bookings in Cal.com automatically?
Yes, in each customer's own account. Your product reads live availability, places a booking, moves it or cancels it, and reacts when someone books or cancels on the other side.
Does it respect each team's own availability rules in Cal.com?
Yes. Working hours, buffers, lead times, resource capacity and routing rules are configured per customer and mapped rather than hard-coded, so an unusual setup works without code from you.
What can I build with the Cal.com integration?
A common starting point: let each customer connect their own Cal.com account, hosted or self-run, so bookings land on the calendar they already keep. Teams also use it for the other use cases listed above, and expose it to agents for governed reads and writes.
How much does the Cal.com integration cost?
It is included. Pricing is based on connected accounts, not on how many connectors you enable, so adding Cal.com does not change your per-connector cost. You can start free with 3 connected accounts.
Add Cal.com to your product
Start free with 3 connected accounts. No sales call required, and no per-customer integration code.