Alerts
Hear about failures and missing events without watching a chart
An alert watches your project's events and tells your team's owners and admins, by inbox and email, when something looks broken. Create them under Analytics > Alerts in Studio, or with the CLI, the API or an agent over MCP.
Alerts read production events and production purchases. They are checked once an hour, at a quarter past, over windows that closed on the hour.
What an alert can watch
| Kind | Fires when | Example |
|---|---|---|
| Too many of an event | An event happens at least so many times, to at least so many people. | purchase_failed 5 times in an hour |
| Too many failures | The share of attempts that failed is clearly above your limit. | upload_failed against upload_completed |
| An event drops | An event falls by your limit against the same window in the weeks before. | $pageview down 50% over 24 hours |
People affected. A count needs at least 2 different people by default, so one device retrying does not fire it. Set it to 1 when a single person matters, such as someone who paid and has no access.
Attempts. For failures, send one event when an attempt fails and another only when it worked. An attempt is either event, so if everything fails the alert reads 100%.
When an alert stays silent
On a small project a quiet window is normal, so an alert says when it cannot tell instead of guessing.
- Not enough volume. Too few events in this window to judge. At 2 purchases a day, no purchases in an hour means nothing, so choose a longer window. A failure alert also needs at least 5 failures before it fires.
- Not enough history. A drop is compared with earlier weeks, and this event was first seen too recently to have two of them. Only time fixes this; the alert starts judging on its own.
How often you hear from it
You get one notice per problem, not one per hour. An alert stays open while the problem lasts, and clears itself after two clean checks and at least six hours, so something flapping stays one notice. People can mute these notices in their notification settings.
Changing what an alert watches, or turning it off, starts it over and closes any open notice within the hour. An alert can only tell you what your events say: a broken release that stops sending events reads as a drop, and an event you never send reads as nothing at all.