--- url: https://docs.notice.cx/tower/alerts.md description: >- What fired, how serious it is, what kind of thing it is, and what you did about it. --- # Alerts An **alert** is a record NoticeOS raises when a number on a site, or in NoticeOS's own collection, is unlikely to be normal, with the evidence attached. The **Alerts** page lists every open alert until it is fixed, snoozed or marked read. Why one fires is in [Alerts](/concepts/alerts). The Alerts page shows what needs attention right now, and how serious it is. ![The Alerts page in the synthetic demo: three open alerts, the last seven days as one row per site, and each open alert against its usual range.](../images/tower-alerts.webp) ## What you see The page starts with a one-line summary and a severity dot: **2 open alerts, both warnings**, or **All clear.** Beside it, **Oldest** shows how long the oldest open alert has been open and **Settled this week** counts what was resolved or acknowledged in the last seven days. Under the summary, **Last 7 days** draws the same alerts on a time axis that ends at **Now**: one row per site, every open alert a bar from when it was first detected to now, and what settled this week a pale closed bar with a green tick. A bar that started more than a week ago is cut at the left edge with its age on it (**since 37d**). The newest open error has a faint red glow. Press an open bar to jump to its row below, expanded; press a closed bar to see that site's settled alerts. Like the summary, the chart covers every site: the filters narrow the list, not the chart. Two tabs follow: **Open** and **History**. Open lists the alerts still open; History lists every settled alert. **Filters** are above the list: a site, a severity (**Any severity**, **Errors**, **Warnings**; History adds **Info**) and a kind (**Any kind**, **Anomalies**, **Opportunities**). When a filter narrows the list, the list shows how many of the open alerts it includes (**3 of 10 open**). The Open list is one board, grouped by site, the site with the worst and newest alert first; each site's heading names it and counts its errors and warnings. Each row describes what happened, and its verb shows which direction is good, with a shape for severity (a circle for an error, a triangle for a warning) and how long ago it was first detected. Where the rule that fired has a normal range, the row draws the reading against it: the usual range as a shaded band, the reading as a dot, **Below normal** or **Above normal** in words, and the figures under it (**19 in 24h**, **usual 41–77**). A metric's usual range is the counts its own rule would not have fired on; a late nightly report is shown against the hours the rule allows; a GA4 quota against the share below which the rule fires. A rule with no range (a failed fetch, a sitemap check) has none drawn. The statistics are under **Evidence** in the expanded row, and a condition checked on several nights is drawn as one bar per night against its usual level. Alerts open for over a week are collapsed under **Open for over a week**, one line naming each and its site, so an old fault is never shown as prominently as a new one. When they are all that is open, they are listed under that heading, not collapsed. The list ends with **That's every open alert.** and the age of the data. Under it, a **Snoozed** panel lists alerts you snoozed, each with when it comes back. History lists settled alerts, newest first, each with its site, what was decided (**Acknowledged**, **resolved 2d ago**) and how long it stayed open, 25 to a page with **Newer** and **Older**. Every alert has two separate fields. **Severity** is how urgent: **error**, **warn** or **info**; only these three use the attention colours. **Kind** is what sort of thing it is: an **anomaly** (something moved when it should not have), an **opportunity** (something worth acting on) or a **milestone** (a win). A milestone is always info-severity, so it never appears in the Open queue; it shows on Home and in History. A green card marks a win; it does not mean that all is well. ## What you can do Each action is on the row it applies to. On a computer with a mouse, **Snooze** and **Resolve** appear at the end of a row when you point at it or move to it with the keyboard; on a phone or a touch screen they are under each row. * **Snooze** moves the alert to the Snoozed panel for a few days or until a date (**Snooze until date**). It returns to the Open list automatically. * **Unsnooze**, in the Snoozed panel, returns a snoozed alert to the Open list early. * **Resolve** closes it. * **Mark read**, after opening the row for the evidence, acknowledges it without closing it. * **Tune** adjusts the rule that fired it. Tuning opens the same two settings as **Settings** > **Alert rules** (**Anomaly sensitivity** and **Longest window**), with a replay of what the new value would have fired. * **File task**, in the opened row, files a task about the condition; the alert stays open until the condition clears. * **Open** the site, from the opened row or from the site's heading. * The filters narrow the list by site, severity and kind. A metric is tested against the mean of its four matching prior weekdays, so a Saturday is compared with Saturdays. A metric averaging 4.6 or more a day is tested one day at a time; a quieter one is tested over the fewest whole days in which a run of zeros could fire, up to **Longest window**, against four earlier windows of the same length. It fires only when the count is improbable against that baseline. A new metric raises no alert until four matching weekdays exist, which takes at least 28 days. An alert that persists stays one alert; a new reading resolves the previous open alert for that metric before the new day is tested. ## States and labels * **All clear.** means no open alert. * **Confirmed 3h ago** means the alert's source checked it recently; **Last known** means nothing has re-checked it since, and it stays open until something does. * In History, a row's caption is its disposition: **Acknowledged**, **Snoozed**, or **Verdict recorded**. A settled alert with no recorded decision shows **no decision recorded**. * A row whose evidence could not be read shows a message in its place. * A comparison the data cannot support shows **not comparable** instead of an uncoloured percentage. ## Related guides * [Alerts](/concepts/alerts), the concept * [Send your own report](/guides/send-your-own-report) * [Settings](/tower/settings) * Flags, severity and kind in [doc 02, Signal contract](../02-signal-contract.md)