Webhook: what it means
DefinitionA webhook is an automatic message that one program sends to another the moment something happens, such as a new booking, a paid invoice or a cancelled visit. It pushes news out instantly instead of waiting for another program to ask for it.
How it works in a service business
With a plain API, the second program must keep asking whether anything is new. A webhook flips this: the scheduler calls a web address you provide as soon as an event occurs. That makes quick chains possible, like posting a new booking to a team chat or starting a follow-up. The tradeoff is reliability: if the receiving address is down, the message can be lost unless the sender retries. A common mistake is exposing a webhook address that anyone can call. Check that messages carry a signature or secret, test with a sample event, and decide what should happen when a delivery fails. Many owners use webhooks through an automation service, not custom code.
Example
Whenever a customer cancels, the scheduler sends a webhook to an automation tool, which posts a note to the office chat so someone can offer the slot to the waitlist.
Where Apex touches this
In progress
Part of this is built. The rest is not. Status as of 2026-10-07; the badge shows the least-built feature involved.
- IG02Webhooks(Rolling out)
- IG03Zapier / Make app(Rolling out)
- IG15Inbound lead webhook (any form)(In progress)
Apex Flow Scheduler is in early access. See how we label status.