Know your smart home is broken before the lights don't turn on.

blueprint:
  name: "Home Health Kit: frost or low temperature alert"
  description: >
    Notifies you when a temperature sensor drops below a limit, for example
    to protect pipes in a cabin, garage or basement. Alerts once per cold spell.
  domain: automation
  author: Home Health Kit
  homeassistant:
    min_version: "2025.4.0"
  input:
    temperature:
      name: Temperature sensor
      selector:
        entity:
          filter:
            - domain: sensor
              device_class: temperature
    limit:
      name: Alert below
      default: 5
      selector:
        number: {min: -30, max: 30, step: 0.5, unit_of_measurement: "°"}
    phone:
      name: Phone
      selector:
        device:
          integration: mobile_app

mode: single
max_exceeded: silent

variables:
  temperature: !input temperature

triggers:
  - trigger: numeric_state
    entity_id: !input temperature
    below: !input limit
    for: {minutes: 10}

actions:
  - domain: mobile_app
    type: notify
    device_id: !input phone
    title: "Low temperature: {{ state_attr(temperature, 'friendly_name') }}"
    message: >
      It is {{ states(temperature) }}{{ state_attr(temperature, 'unit_of_measurement') or '' }} now.