Every property gets its own API key and signed, real-time webhooks for new, changed and cancelled reservations. Feed a door access system, a BI dashboard, your accounting tool or a bar POS without exporting a spreadsheet.
reservation.created
Delivered on first attempt
reservation.updated
Attempt 1 failed, retrying in 1 minute
reservation.updated
Delivered on attempt 2
reservation.cancelled
Delivered on first attempt
Signed with HMAC-SHA256 · Retries after 1, 5 and 30 minutes
In your daily workflow
Subscribe your HTTPS endpoints to reservation.created, reservation.updated and reservation.cancelled. Each event arrives as JSON with dates, rooms, room types, guests, source and special requests, and updates also carry the previous values of the fields that changed.
Generate a key on the Developers page in Roomismo and send it in the x-api-key header of a GraphQL request. The key is tied to one property, can be paused or regenerated at any time, and Roomismo stores only a hash of it.
Create and update service requests from a restaurant, bar or spa app through the same API, with products, quantities and VAT, so a pool bar order can be charged to the guest's room and show up on their reservation.
Webhooks fail in the real world: servers restart, certificates expire, deploys go wrong. Roomismo signs, retries and logs every delivery so your integration can recover without anyone re-entering data.
Every delivery carries an X-Roomismo-Signature header with a timestamp and an HMAC-SHA256 signature made with your property's secret, so your endpoint can reject forged or replayed calls. You can regenerate the secret whenever you need to.
If your endpoint does not answer with a 2xx status within 30 seconds, Roomismo tries again after 1 minute, 5 minutes and 30 minutes. If all four attempts fail, users with access to the property settings get an email.
The Developers page lists every event with its status, response code, number of attempts, last error and full payload. A failed event can be sent again with one click once your endpoint is fixed.
Each endpoint is pinned to a payload version (currently 2026-01-01), and you can register several endpoints per event. A future payload change reaches your integration only when you switch versions.
The Developers page documents each operation available to API keys, with its arguments, return fields and a ready-to-copy example request.
We are building a Model Context Protocol server so AI agents such as Claude or ChatGPT can work with your Roomismo data, with the same per-property access rules. Ask about it in your demo.
POST https://your-system.example.com/roomismo
X-Roomismo-Event: reservation.updated
X-Roomismo-Signature: t=1767225600,v1=5f2b9c…
{
"id": "evt_a1B2c3",
"object": "event",
"type": "reservation.updated",
"api_version": "2026-01-01",
"data": {
"object": {
"reservationNumber": "R-10482",
"status": "new",
"arrivalDate": "2026-07-14T00:00:00.000Z",
"departureDate": "2026-07-18T00:00:00.000Z",
"source": "website",
"mainGuest": { "firstname": "Maria", "lastname": "Papadopoulou" },
"rooms": [{ "room": "204", "roomType": "Double Sea View", "guestCount": 2 }]
},
"previous_attributes": { "departureDate": "2026-07-17T00:00:00.000Z" }
}
}Walk through the features with our team and find the setup that fits your property.