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Rules

The rules screen is the alert‑condition authoring surface — a table of every rule in the project, the form for creating or editing a rule, and the detail view for inspecting a rule’s configuration and its alert history. It lives under the Alerts parent at /projects/:id/rules.

Rule editor form

What you see

Section titled “What you see”

Rule list

Section titled “Rule list”

A paginated table listing every alert rule configured for the project. Columns:

Column Description
Severity Colour-coded badge — critical or warning
Scope Asset, Class, or Group — the evaluator resolves most-specific-wins
Target The asset, class, or group the rule targets
Condition Human-readable summary — e.g. “battery_v falls below 3.4 V (×2)”
Status Active (evaluating) or Paused (not evaluating)

The scrubber toggles between All, Active, and Paused. Click any column header to sort.

Rule editor form

Section titled “Rule editor form”

Click Create rule or edit an existing rule to open the rule editor — a sentence-style form in four sections:

1. Target — what the rule watches:

  • Scope toggle — Asset, Class, or Group. Asset scope picks one asset; class scope applies to every asset of a class (new assets of the class inherit it); group scope covers every asset beneath a group. When rules overlap, the most specific wins (asset ▷ class ▷ group).
  • Target picker — choose the specific asset, class, or group. A class scope shows a live “applies to N assets” preview of its blast radius.

2. Condition — what trips it, written as a sentence (Alert when …):

  • Metric picker — choose from the catalogue (e.g. battery_v, flow_rate_lpm, level_m, pressure_kpa).
  • Comparator picker — lt (falls below) / gt (rises above) / outside_band (moves outside a band) / rate (changes faster than) / pct_over_baseline (exceeds a baseline by) / min_over_window (stays above — flow only) / stale (reports no data for).
  • Threshold fields — depend on the comparator: tripValue for lt/gt; tripValue + tripValueHi for outside_band; tripValue + windowSecs for rate and min_over_window; tripValue + baseline + windowSecs for pct_over_baseline; windowSecs alone for stale.

3. Reduce false alarms — how it fires:

  • Debounce — the number of consecutive breaching readings required before the rule opens an alert. Prevents transient noise from firing false alarms.
  • Clear value (optional) — the healthy value the metric must recover past before the rule resolves (hysteresis). Defaults to the trip value when omitted.

4. Classification — how it’s raised:

  • Severity — Warning or Critical. (Offline alerts come from the stale comparator, not a severity you pick.)
  • Category (optional) — a grouping label chosen from a picklist (e.g. Reservoir level, Pressure, Flow, Device health, Leak).

Rule detail view

Section titled “Rule detail view”

Click any rule row to open the rule detail panel — a read‑only view showing the rule’s full configuration, creation timestamp, and a list of every alert it has ever generated (with severity, opened date, and current state). From this panel you can Edit the rule (opens the editor pre‑filled) or Pause / Resume it.

Key interactions

Section titled “Key interactions”

Create a rule — from the Create rule button. The editor opens with empty fields and the scope defaulting to Class. Rules are active immediately on save unless the Paused toggle is set.

Edit a rule — from the rule row’s overflow menu or the detail panel’s Edit button. Changing a rule’s condition or severity affects only future evaluations — existing open alerts from the old configuration stay in their current state.

Pause / resume — from the overflow menu or detail panel. Pausing stops the rule from evaluating. Existing open alerts remain active and must be acknowledged or resolved independently. Resuming re‑enables evaluation from the next sweep.

Delete a rule — from the overflow menu. Prompts confirmation. Deleting a rule does not close its existing alerts — they stay in the queue with the rule annotated as “deleted”. The rule cannot be recovered; create a new one instead.

Section titled “Related”