Example of an alert that sends a push message to the Android App (using notify)?

I have no issue configuring this as part of an automation, for example:

- id: '1581536561851'
  alias: Garage Door 1 is Open
  description: ''
  trigger:
  - entity_id: cover.garage_door_1
    for: '"00:00:15"'
    from: closed
    platform: state
    to: open
  condition: []
  action:
  - data:
      data:
        actions:
        - action: close_garage_door_1
          title: Close Garage Door
      message: ''
      title: Garage Door 1 is Open
    service: notify.mobile_app_XXX_phone

After 15 minutes of the door being in an open state, I get the push message.

What I am having trouble with is doing this within an alert, for example, this is working with SMTP (which my carrier translates to SMS) today:

alert:
  garage_door_1:
    name: Garage Door 1 is open
    entity_id: cover.garage_door_1
    state: 'open'
    repeat: 15
    can_acknowledge: true
    skip_first: true
    notifiers:
      - SMS

notify:
  - name: SMS
    platform: smtp
    sender: !secret smtp_username
    recipient:
      - !secret sms_XXX
    server: smtp.gmail.com
    port: 587
    encryption: starttls
    username: !secret smtp_username
    password: !secret smtp_password

How can I configure this so the alert is able to send a push message - any sample “notifier” code you can share?

Never got this working using an alert; but, I did it it running via an automation.

The only downside is that it has to keep running every X minutes.

Added logic to make sure it don’t alert again until 15 minutes after the last alert:

- id: '1581536561851'
  alias: Garage Door 1 is Open
  description: ''
  trigger:
  - minutes: /5
    platform: time_pattern
  condition:
  - condition: and
    conditions:
    - condition: state
      entity_id: cover.garage_door_1
      for:
        minutes: 15
      state: open
    - above: '14'
      condition: numeric_state
      entity_id: cover.garage_door_1
      value_template: '{{ ((as_timestamp(now()) - as_timestamp(states.automation.garage_door_1_is_open.attributes.last_triggered))
        / 60) | round(0) }}'
  action:
  - data:
      data:
        actions:
        - action: close_garage_door_1
          title: Close Garage Door
      title: Garage Door 1 is Open
      message: Door was opened {{ ((as_timestamp(now()) - as_timestamp(states.cover.garage_door_1.last_changed))
        / 60) | round(0) }} minutes ago.
    service: notify.mobile_app_XXX_phone


- id: '1581536932598'
  alias: Close Garage Door 1
  description: ''
  trigger:
  - event_data:
      action: close_garage_door_1
    event_type: mobile_app_notification_action
    platform: event
  condition: []
  action:
  - entity_id: cover.garage_door_1
    service: cover.close_cover