Home Assistant

Home Assistant — Living Skill

Snapshot of a production skill as of 2026-07-25. Instance names are anonymised to instance-a / instance-b on purpose — do not replace them with real names.

Session Start: Read living-checklist.md first — known pitfalls and proven solutions.

System Reference

Devices & Entities

Adapt this table to your setup. Example structure:

Smart plug note: Binary devices (no dimming) are often used seasonally (e.g. floor lamp vs. decorative light). When switching, remember to swap which automations are active.

Proven Approaches

Writing Automations

• Always verify that trigger entities actually exist before writing automation YAML
• Use from: as a YAML list, never as a scalar (see living-checklist)
• Check the HA developer tools (States tab) to confirm entity names and current states
• Test triggers manually via Developer Tools → Events before going live

Debugging an Automation That Never Fires

1. Check the automation trace (Settings → Automations → your automation → Traces)
2. Verify trigger entity exists and changes state as expected
3. Verify conditions evaluate to true at the moment you expect the trigger
4. Check if the automation is enabled

Presence-Based Automations

• State restore on HA restart can re-trigger presence automations (see living-checklist)
• Test: restart HA and observe which automations fire unexpectedly

Common Automation Patterns

Light follows physical switch

trigger:
  - platform: state
    entity_id: light.<zigbee_bulb>
    from: [unavailable, unknown, 'off']
    to: 'on'
condition:
  - condition: state
    entity_id: light.<smart_plug>
    state: 'off'
action:
  - service: light.turn_on
    entity_id: light.<smart_plug>

TV scene (cinema mode)

trigger:
  - platform: state
    entity_id: media_player.tv
    to: 'on'
action:
  - service: light.turn_on
    entity_id: light.<room_light>
    data:
      brightness_pct: 5
      color_temp: 500
      transition: 15
  - delay: "00:00:15"
  - service: light.turn_off
    entity_id: light.<smart_plug>

Dead man's switch / inactivity alert

trigger:
  - platform: time_pattern
    hours: "/1"
condition:
  - condition: template
    value_template: >
      {{ (now() - states.light.<entity>.last_changed).total_seconds() > 50400 }}
  - condition: state
    entity_id: input_boolean.alert_sent
    state: 'off'
action:
  - service: notify.<your_notification_service>
    data:
      message: "No activity detected for 14 hours."
  - service: input_boolean.turn_on
    entity_id: input_boolean.alert_sent

Open TODOs

• Native push notifications via HA Companion App (iOS/macOS) — registers notify.mobile_app_<device> automatically after app install — allows interruption-level: critical to bypass silent mode
• [Add your own TODOs here]

Session End

After each session: write new learnings, bug fixes, pitfalls, or proven solutions to living-checklist.md. Format: date, task context, learning, rule. Update revisionslog.md if automations or configuration changed.