Created a webhook channel but it never receives anything

That is the most common setup gap, so you are in good company. Channels are opt-in per source. Here is how to fix it: 1. Open the notification channel you created. 2. Add a subscription. You choose a source type and the id of that source. 3. If you want this channel to receive alerts for one specific monitor, subscribe it with source type uptime check and that monitor's id. Same idea for a heartbeat or an alert trigger. 4. If you want the channel to receive everything that happens in the organization, subscribe it with source type organization and your organization's own id. This is the catch-all. A few notes that will save you time later: subscriptions are idempotent, so re-adding the same one is harmless. The source has to belong to the same organization as the channel, otherwise the request is rejected. And a channel that is set to inactive is skipped even if it has valid subscriptions.