Guest messaging and CRM

A guest messaging product or a CRM follows a guest through a stay: a booking arrives, a message goes out before arrival, another after departure, and the history stays in one place. This recipe shows what the API gives you for that.

Read the next section first, because it decides what you can build: by default the API tells you when a stay happens and what was booked, and it does not tell you who the guest is or how to reach them.

What the campground gets

Messages that follow the stay on their own: before arrival, at check-in, after departure, and stopped when a booking is cancelled.
A CRM that learns about new, changed and cancelled bookings as they happen.

Grondia sends some guest emails itself, such as the booking confirmation and the cancellation. Agree with the campground what your product sends on top of them, so a guest does not get the same news twice.

Personal data comes first

Guest personal data is redacted by default on both lists. It is available on request, decided case by case with Felix (Credentials; the Personal data guide lists what each call returns).

You read	By default	With the personal-data scope
Bookings	Dates, pitch or pitch type, number of guests, status, total and references. `guest_first_name` and `guest_last_name` come back empty and `guest_email` as `"[redacted]"`	`bookings:pii` fills the two names and the email. A booking has no phone number and no postal address either way
Customers	`id` and `date_joined`. `first_name` and `last_name` come back empty, `email` as `"[redacted]"` and `phone_number` empty	`customers:pii` fills the two names, the email and the phone number

Neither personal-data scope can be created in the admin. Without one, your product cannot reach a guest: there is no address to send to. Do not import "[redacted]" as an email address, and do not treat an empty name as a missing guest.

If you need contact data, write to Felix, felix@grondia.com, or to Siro, siro@grondia.com, say which campground and which fields, and why. Webhook bodies never carry personal data, with or without the scopes.

Scopes

Scope	Opens	Who can create the key
`bookings:read`	`GET bookings/`, `GET bookings/{id}/`	The campground’s administrator
`customers:read`	`GET customers/`	The campground’s administrator
`webhooks:write`	The webhook endpoints, to receive events instead of polling	On request: ask Felix or Siro
`bookings:pii`, `customers:pii`	Lifts the redaction above	On request, case by case

A key without webhooks:write still works: poll GET bookings/?updated_since=<timestamp>, which returns bookings changed since then, oldest change first (Syncing changes).

How the pieces fit

Anna Müller books pitch A12 at Camping Beispielsee for 14 to 17 July.

Grondia: Anna Müller books pitch A12
Grondia to Your messaging or CRM product: booking.booked. Ids, dates, pitch type
Your messaging or CRM product to Grondia: GET bookings/{id}/
Grondia to Your messaging or CRM product: The booking, guest fields redacted unless bookings:pii
Your messaging or CRM product: Schedule the pre-arrival message for the day before
Grondia to Your messaging or CRM product: booking.changed. Anna moves her arrival
Your messaging or CRM product to Grondia: GET bookings/{id}/
Your messaging or CRM product: Reschedule
Grondia to Your messaging or CRM product: guest.checked_in
Your messaging or CRM product: Send the welcome message
Grondia to Your messaging or CRM product: guest.checked_out
Your messaging or CRM product: Send the thank-you message

The webhook says that something happened and names the booking. The booking itself, and who the guest is, you fetch.

The events

Register one endpoint with POST webhooks/. booking.booked, booking.changed and guest.created are opt-in: an endpoint that leaves event_types empty does not receive them, so name them.

curl https://api.campone.ch/api/v1/public/webhooks/ \
  -H "Authorization: Bearer ck_a1b2cXXXXXXXXXXXXXXXXXXXXXXXX" \
  -H "Content-Type: application/json" \
  -d '{
    "url": "https://crm.example.com/hooks/grondia",
    "event_types": ["booking.booked", "booking.changed", "booking.cancelled",
                    "guest.checked_in", "guest.checked_out"]
  }'

The answer holds the signing secret once. Verify X-Grondia-Signature on every delivery and answer 2xx within 10 seconds; the webhook reference describes the headers, and a failed delivery is retried up to five more times. The Webhooks guide shows the signature check in code and the delivery log.

Event	Opt-in	Use it to
`booking.booked`	Yes	A new booking, whatever its first status. Create the contact or deal, start the sequence
`booking.changed`	Yes	Dates, guests, price or status changed, or the booking was confirmed. Reschedule
`booking.cancelled`	No	Stop the sequence
`guest.checked_in`	No	The welcome message
`guest.checked_out`	No	The thank-you message or a review request
`guest.created`	Yes	A guest profile now exists. Carries an id and a reference only; read the section below before you rely on it

The first five share one body, which holds dates and a pitch type but no guest and no pitch number:

{
  "event": "booking.booked",
  "tenant": "beispielsee",
  "booking": {
    "id": 51277,
    "external_reference": "",
    "booking_reference": "7F3A9C21DE",
    "status": "confirmed",
    "check_in": "2026-07-14",
    "check_out": "2026-07-17",
    "site_type_code": "motorhome",
    "total": "105.00",
    "currency": "CHF",
    "updated_at": "2026-07-01T08:30:01.204117+00:00"
  }
}

The body is built when the delivery is made, so it shows the booking as it is then. check_in and check_out are the campground’s local calendar dates: schedule your messages in the campground’s time zone (Europe/Zurich for a Swiss campground), not in yours.

Read the booking and the customer

GET bookings/{id}/ answers the event. With the default scopes, Anna’s booking looks like this:

{
  "id": 51277,
  "booking_reference": "7F3A9C21DE",
  "guest_first_name": "",
  "guest_last_name": "",
  "guest_email": "[redacted]",
  "site_id": 9012,
  "site_number": "A12",
  "site_category": "Motorhome pitch",
  "check_in_date": "2026-07-14",
  "check_out_date": "2026-07-17",
  "num_adults": 2,
  "num_youth": 0,
  "num_children": 0,
  "status": "confirmed",
  "total_price": "105.00",
  "created_at": "2026-07-01T08:30:00.918342Z",
  "updated_at": "2026-07-01T08:30:01.204117Z",
  "external_reference": "",
  "channel": ""
}

The customer list holds guests who have an account at the campground, newest first. With the default scopes Anna appears without her name and her contact details:

{
  "id": 1042,
  "email": "[redacted]",
  "first_name": "",
  "last_name": "",
  "phone_number": "",
  "date_joined": "2026-06-20T14:03:22.417051Z"
}

Both lists come in pages of 50 (up to 200 with ?page_size=200).

Edge cases

Situation	What happens	What to do
You want to message a guest	The booking has no usable email by default	Agree `bookings:pii` with Felix, or get the contact data from the campground
A booking is `pending`, `abandoned` or `cancelled`	Only `confirmed` is firm. A `pending` booking may still be released, and an `abandoned` one never was firm (life of a booking)	Read `status` before you send anything
The campground does not record check-in or check-out	No `guest.checked_in` or `guest.checked_out`	Fall back to `check_in` and `check_out`
The same guest books twice	Two bookings, and a booking carries no guest id	With `bookings:pii`, match on email. Without it you cannot tell
A guest booked without an account	They are in bookings, not in the customer list	Treat bookings as your source for stays
`guest.created` arrives	See below	Do not rely on it to build a contact
You need a consent flag, or the guest’s language	Neither can be read through the API. When you create a booking you can send `language` (Create a booking)	Ask the campground what it may send, and in which language
Your endpoint is down	The delivery is retried five more times, then given up	Catch up with `GET bookings/?updated_since=` (Syncing changes)

`guest.created`

The event carries a guest id (a UUID), a guest_number such as GST-000123 and created_at, and nothing else. You cannot do much with it, for three reasons:

No endpoint of the API returns a guest by id or guest_number, and no booking or customer response carries either. You cannot join the event to a booking or a customer.
The customer list is a different thing: guests with an account, with integer ids. A guest profile also exists for guests without one, such as walk-ins.
A replay of a guest.created delivery is accepted (202) but sends nothing, because the delivery log cannot store a guest id. Do not plan on replay for it.

Use it as a signal that a new guest exists at the campground, or leave it out and derive your contacts from bookings. If the campground wants every new guest in a spreadsheet or another tool, the Zapier app fetches the full guest for its “New guest” trigger.

What you cannot do

The API reads guests and bookings. There is no endpoint to create or change a guest on its own, to add a note to a booking, or to send a message on Grondia’s behalf. Writing a guest or a note back to Grondia is possible through the Zapier app only.

Go-live checklist

You agreed with Felix or Siro which personal data you get, and from whom, before you built the sending.
Nothing in your product treats "[redacted]" as an email address or an empty name as a missing guest.
booking.booked, booking.changed and guest.created (if you use it) are in event_types, because they are opt-in.
Your handler fetches the booking, and sends only when its status is confirmed.
A change or cancellation moves or stops a scheduled message.
Messages go out in the campground’s time zone, and you agreed with the campground what Grondia sends itself.
Your handlers are idempotent: key a booking on its id.
A sweep on updated_since catches what a downtime missed.

When the product works, ask for the review: Partner program.

Personal data: what each call returns, what a webhook carries and how to ask for access.
Webhooks, Syncing changes and Errors: the guides behind the events and the catch-up.
Zapier: the no-code way to write a guest or a note back.
Channel managers: the recipe for products that create bookings.