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OCLauncher Team
OCLauncher Team

Posted on • Originally published at favcrm.io

Build a Booking Backend Your AI App Can Actually Use

#ai #mcp #backend #tutorial

In the previous article, we connected an agent to FavCRM and discovered its 165 typed tools.

Now we build something real: a booking flow that takes actual bookings — services, open slots, a confirmed booking, and a customer record that persists.

No mock arrays. Every call in this walkthrough writes a row.

The flow we are building 

create_service  →  get_available_slots  →  create_booking  →  confirm_booking
                                                                    ↓
                                                          customer record persisted
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The examples use the favcrm CLI because it is reproducible. An agent in Cursor or Claude makes the exact same MCP calls — it just decides the arguments itself.

Always inspect a tool before the first call:

favcrm tool describe create_service
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The schema tells you the required fields. The examples below are minimal — your real arguments come from that schema.

Step 1 — Create a service

A service is the thing a customer books: a haircut, a class, a consultation.

favcrm tool call create_service '{
  "name": "Intro Consultation",
  "durationMinutes": 30,
  "price": "0.00"
}'
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The call returns a service id. That id is real and persisted — list it back to confirm:

favcrm tool call list_services '{}'
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Step 2 — Check available slots

get_available_slots reads the service duration, staff and resource availability, and existing bookings, then returns the open times.

favcrm tool call get_available_slots '{
  "serviceId": "<service-id>",
  "date": "2026-06-01"
}'
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This is the part you would otherwise build yourself — a calendar that knows about capacity and clashes. Here it is one call.

Step 3 — Create the booking 

favcrm tool call create_booking '{
  "serviceId": "<service-id>",
  "start": "2026-06-01T14:30:00Z",
  "customer": { "name": "Amy Chan", "email": "amy@example.com" }
}'
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create_booking is a write tool. It checks the slot is still free, rejects double-bookings, and persists the row. If the slot was taken between Step 2 and Step 3, the call fails cleanly — the agent can re-read slots and retry.

Step 4 — Confirm it

A created booking is not necessarily a confirmed one. confirm_booking moves it into a confirmed state — the trigger for reminders and, if you want it, a payment link.

favcrm tool call confirm_booking '{ "bookingId": "<booking-id>" }'
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Step 5 — The customer record built itself

You never called a "create customer" step. The customer passed to create_booking was upserted into the CRM automatically — a real crm_accounts record with contact details, booking history, and tags.

Verify it:

favcrm tool call list_bookings '{}'
favcrm tool call get_booking_detail '{ "bookingId": "<booking-id>" }'
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The booking detail carries the linked customer. Next time the same email books, it attaches to the same record — history accumulates without a data model you had to design.

Optional — Take payment

If the service has a price, issue an invoice:

favcrm tool call create_invoice '{ "bookingId": "<booking-id>" }'
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That returns a payable invoice backed by Stripe. Still one call; still a real record.

What you just did

You stood up a booking backend — services, availability, clash detection, confirmations, customer records, payments — without designing a schema, writing a migration, or reconciling a webhook.

The agent decided what to do. FavCRM was where it happened. Every step returned a persisted record, not a stub.

That is the practical meaning of a headless CRM: your AI builds the interface, and a real backend stands behind every call.

Try the flow on a free workspace: favcrm.io/campaigns/headless-crm

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