Agent Skills: Home Assistant Automation Expert

Home Assistant Automation Expert

Master Home Assistant automations, scripts, blueprints, and Jinja2 templating with confidence.

Before You Start

This skill prevents common automation mistakes including:

1. Incorrect trigger syntax - Using deprecated formats or invalid entity IDs
2. Missing condition operators - Forgetting and/or/not conjunctions
3. Jinja2 template errors - Undefined variables or incorrect filter usage
4. Blueprint parameterization issues - Missing !input substitutions or misaligned selectors

Quick Reference: Automation Structure

Basic Automation Format

automation: !include automations.yaml

Single Automation File

- alias: "My Automation"
  description: "What this automation does"
  trigger: ...
  condition: ...
  action: ...
  mode: single

Triggers Quick Reference

State Trigger

trigger:
  platform: state
  entity_id: light.bedroom
  from: "off"
  to: "on"
  for:
    minutes: 5

Numeric State Trigger

trigger:
  platform: numeric_state
  entity_id: sensor.temperature
  above: 25
  below: 30

Time Trigger

trigger:
  platform: time
  at: "10:30:00"

Time Pattern Trigger

trigger:
  platform: time_pattern
  hours: "*/2"  # Every 2 hours
  minutes: 0

Device Trigger

trigger:
  platform: device
  device_id: abc123...
  domain: light
  type: turned_on

Event Trigger

trigger:
  platform: event
  event_type: call_service
  event_data:
    domain: light

MQTT Trigger

trigger:
  platform: mqtt
  topic: home/front_door/status
  payload: "opened"

Webhook Trigger

trigger:
  platform: webhook
  webhook_id: my_webhook_id

Sun Trigger

trigger:
  platform: sun
  event: sunrise
  offset: "-00:30:00"  # 30 min before sunrise

Zone Trigger

trigger:
  platform: zone
  entity_id: device_tracker.john
  zone: zone.home
  event: enter

Template Trigger

trigger:
  platform: template
  value_template: "{{ state_attr('light.bedroom', 'brightness') > 200 }}"

Conditions Quick Reference

State Condition

condition:
  - condition: state
    entity_id: light.bedroom
    state: "on"

Numeric State Condition

condition:
  - condition: numeric_state
    entity_id: sensor.temperature
    above: 20
    below: 25

Time Condition

condition:
  - condition: time
    after: "08:00:00"
    before: "20:00:00"
    weekday:
      - mon
      - tue
      - wed

Sun Condition

condition:
  - condition: sun
    after: sunrise
    before: sunset

Template Condition

condition:
  - condition: template
    value_template: "{{ states('light.bedroom') == 'on' }}"

Combining Conditions

condition:
  - condition: and
    conditions:
      - condition: state
        entity_id: light.bedroom
        state: "on"
      - condition: numeric_state
        entity_id: sensor.temperature
        above: 20

condition:
  - condition: or
    conditions:
      - condition: state
        entity_id: binary_sensor.motion
        state: "on"
      - condition: state
        entity_id: light.bedroom
        state: "on"

Actions Quick Reference

Call Service Action

action:
  - service: light.turn_on
    target:
      entity_id: light.bedroom
    data:
      brightness: 255
      color_temp: 366

Call Service (Multiple Targets)

action:
  - service: light.turn_on
    target:
      entity_id:
        - light.bedroom
        - light.living_room
      area_id: downstairs

Choose (If/Then/Else)

action:
  - choose:
      - conditions:
          - condition: state
            entity_id: light.bedroom
            state: "on"
        sequence:
          - service: light.turn_off
            target:
              entity_id: light.bedroom
      - conditions:
          - condition: state
            entity_id: light.bedroom
            state: "off"
        sequence:
          - service: light.turn_on
            target:
              entity_id: light.bedroom
    default:
      - service: notification.send
        data:
          message: "Unable to determine light state"

Repeat (Loop)

action:
  - repeat:
      count: 3
      sequence:
        - service: light.toggle
          target:
            entity_id: light.bedroom
        - delay:
            seconds: 1

Delay

action:
  - delay:
      minutes: 5

Wait for Trigger

action:
  - wait_for_trigger:
      platform: state
      entity_id: binary_sensor.motion
      to: "off"
    timeout:
      minutes: 30
  - service: light.turn_off
    target:
      entity_id: light.bedroom

Parallel Actions

action:
  - parallel:
      - service: light.turn_off
        target:
          entity_id: light.bedroom
      - service: switch.turn_off
        target:
          entity_id: switch.fan

Automation Modes

mode: single  # Default - cancel previous run
mode: restart  # Restart on retrigger
mode: queued  # Queue up to 10 retriggered runs
mode: parallel  # Allow multiple simultaneous runs
mode: queued  # with max: 10  # Limit queued runs

Jinja2 Template Cheatsheet

Common Variables

• states('entity.id') - Get entity state
• state_attr('entity.id', 'attribute') - Get entity attribute
• now() - Current datetime
• as_timestamp('2024-01-01') - Convert to timestamp
• trigger - Trigger object (if in trigger template)

Filters

{{ value | float(0) }}  # Convert to float with default
{{ value | int(0) }}  # Convert to int with default
{{ value | round(2) }}  # Round to 2 decimal places
{{ value | timestamp_custom("%Y-%m-%d") }}  # Format timestamp
{{ value | replace("old", "new") }}  # Replace string
{{ value | lower }}  # Lowercase
{{ value | upper }}  # Uppercase
{{ value | length }}  # Get length
{{ list | list }}  # Convert to list

Conditionals

{% if states('light.bedroom') == 'on' %}
  Light is on
{% elif states('light.bedroom') == 'off' %}
  Light is off
{% else %}
  Unknown
{% endif %}

Loops

{% for entity in states.light %}
  {{ entity.name }}: {{ entity.state }}
{% endfor %}

Math Operations

{{ 5 + 3 }}  # Addition
{{ 10 - 4 }}  # Subtraction
{{ 3 * 4 }}  # Multiplication
{{ 20 / 4 }}  # Division
{{ 17 % 5 }}  # Modulo (remainder)

String Operations

{{ "hello " + "world" }}  # Concatenation
{{ value is string }}  # Type checking
{{ value is number }}
{{ value is defined }}  # Check if variable exists
{{ value | default("fallback") }}  # Provide default

Debugging Templates

Use Developer Tools > Template in Home Assistant UI to test templates in real-time.

Blueprint Creation Basics

Blueprint Structure

blueprint:
  name: "Friendly Name"
  description: "What this blueprint does"
  domain: automation
  source_url: "https://github.com/user/repo/path/to/blueprint.yaml"

  input:
    my_light:
      name: "Light to control"
      description: "The light entity to control"
      selector:
        entity:
          domain: light

    brightness_level:
      name: "Brightness"
      description: "Brightness percentage (0-100)"
      selector:
        number:
          min: 0
          max: 100
          unit_of_measurement: "%"

    duration:
      name: "Duration"
      description: "How long to stay on"
      selector:
        number:
          min: 1
          max: 60
          unit_of_measurement: "minutes"

    my_bool:
      name: "Enable feature"
      selector:
        boolean:

trigger: ...
condition: ...
action:
  - service: light.turn_on
    target:
      entity_id: !input my_light
    data:
      brightness: !input brightness_level

Blueprint Selectors

# Entity selector
selector:
  entity:
    domain: light

# Device selector
selector:
  device:
    integration: zwave
    manufacturer: Philips

# Area selector
selector:
  area:

# Number selector
selector:
  number:
    min: 0
    max: 100
    step: 5
    unit_of_measurement: "%"

# Text selector
selector:
  text:
    multiline: true

# Boolean selector
selector:
  boolean:

# Select (dropdown)
selector:
  select:
    options:
      - label: "Option 1"
        value: "value1"
      - label: "Option 2"
        value: "value2"

Common Mistakes to Avoid

❌ Don't: Use old trigger format

trigger:
  - platform: state
    entity_id: light.bedroom

✅ Do: Use nested structure

trigger:
  - platform: state
    entity_id: light.bedroom
    to: "on"

❌ Don't: Mix trigger and condition logic

trigger:
  - platform: state
    entity_id: light.bedroom
    to: "on"
condition:
  - condition: state
    entity_id: light.bedroom
    to: "on"  # Redundant!

✅ Do: Use trigger for change detection, condition for state verification

trigger:
  - platform: state
    entity_id: light.bedroom
condition:
  - condition: numeric_state
    entity_id: sensor.temperature
    above: 20  # Additional check

❌ Don't: Forget entity_id in service calls

action:
  - service: light.turn_on
    data:
      brightness: 255

✅ Do: Specify target entity

action:
  - service: light.turn_on
    target:
      entity_id: light.bedroom
    data:
      brightness: 255

Best Practices

1. Use descriptive alias names - Make automation purposes clear
2. Add descriptions - Explain why the automation exists
3. Test with Developer Tools - Verify templates before deployment
4. Use choose for complex logic - More readable than multiple automations
5. Organize by room or function - Use !include to split large files
6. Set appropriate mode - Choose single/restart/queued based on use case
7. Add for: condition - Prevent false triggers from brief state changes
8. Use templates for flexibility - Enable parameter passing in blueprints

Troubleshooting

Template Shows "Error"

• Check template in Developer Tools > Template
• Verify entity IDs exist: homeassistant.entity_ids
• Use | default("value") filter for optional attributes

Automation Doesn't Trigger

• Verify entity IDs and state values (case-sensitive)
• Check trigger.yaml syntax with YAML validator
• Review automation logs in Settings > Developer Tools > Logs

Blueprint Input Not Working

• Verify !input variable_name syntax (YAML 1.2 tag)
• Check selector type matches input type
• Ensure blueprint is in correct folder: config/blueprints/automation/

Jinja2 Syntax Error

• Check for undefined variables - use | default()
• Verify filter syntax: value | filter_name(arg)
• Don't use quotes inside quotes without escaping

Official Resources

• Home Assistant Automation Docs
• Home Assistant Scripts
• Jinja2 Templating Guide
• Blueprint Documentation
• Condition Types
• Trigger Types
• Template Integration