---
title: "Script Syntax"
description: "Documentation for the Home Assistant Script Syntax."
toc: true
no_toc: true
---
Scripts are a sequence of {% term actions %} that Home Assistant will execute. Scripts are available as an entity through the standalone [Script integration] but can also be embedded in {% term automations %} and [Alexa/Amazon Echo] configurations.
When the script is executed within an automation the `trigger` variable is available. See [Available-Trigger-Data](/docs/automation/templating/#available-trigger-data).
The script syntax basic structure is a list of key/value maps that contain actions. If a script contains only 1 action, the wrapping list can be omitted.
All actions support an optional `alias`.
```yaml
# Example script integration containing script syntax
script:
example_script:
sequence:
# This is written using the Script Syntax
- alias: "Turn on ceiling light"
service: light.turn_on
target:
entity_id: light.ceiling
- alias: "Notify that ceiling light is turned on"
service: notify.notify
data:
message: "Turned on the ceiling light!"
```
{{ page.content | markdownify | toc_only }}
## Call a Service
The most important one is the action to call a service. This can be done in various ways. For all the different possibilities, have a look at the [service calls page].
```yaml
- alias: "Bedroom lights on"
service: light.turn_on
target:
entity_id: group.bedroom
data:
brightness: 100
```
### Activate a Scene
Scripts may also use a shortcut syntax for activating scenes instead of calling the `scene.turn_on` service.
```yaml
- scene: scene.morning_living_room
```
## Variables
The variables action allows you to set/override variables that will be accessible by templates in actions after it. See also [script variables] for how to define variables accessible in the entire script.
{% raw %}
```yaml
- alias: "Set variables"
variables:
entities:
- light.kitchen
- light.living_room
brightness: 100
- alias: "Control lights"
service: light.turn_on
target:
entity_id: "{{ entities }}"
data:
brightness: "{{ brightness }}"
```
{% endraw %}
Variables can be templated.
{% raw %}
```yaml
- alias: "Set a templated variable"
variables:
blind_state_message: "The blind is {{ states('cover.blind') }}."
- alias: "Notify about the state of the blind"
service: notify.mobile_app_iphone
data:
message: "{{ blind_state_message }}"
```
{% endraw %}
### Scope of Variables
Variables have local scope. This means that if a variable is changed in a nested sequence block, that change will not be visible in an outer sequence block.
Inside the `if` sequence the `variables` action will only alter the `people` variable for that sequence.
{% raw %}
```yaml
sequence:
# Set the people variable to a default value
- variables:
people: 0
# Try to increment people if Paulus is home
- if:
- condition: state
entity_id: device_tracker.paulus
state: "home"
then:
# At this scope and this point of the sequence, people == 0
- variables:
people: "{{ people + 1 }}"
# At this scope, people will now be 1 ...
- service: notify.notify
data:
message: "There are {{ people }} people home" # "There are 1 people home"
# ... but at this scope it will still be 0
- service: notify.notify
data:
message: "There are {{ people }} people home" # "There are 0 people home"
```
{% endraw %}
## Test a Condition
While executing a script you can add a condition in the main sequence to stop further execution. When a condition does not return `true`, the script will stop executing. There are many different conditions which are documented at the [conditions page].
<div class='note'>
The `condition` action only stops executing the current sequence block. When it is used inside a [repeat](#repeat-a-group-of-actions) action, only the current iteration of the `repeat` loop will stop. When it is used inside a [choose](#choose-a-group-of-actions) action, only the actions within that `choose` will stop.
</div>
```yaml
# If paulus is home, continue to execute the script below these lines
- alias: "Check if Paulus is home"
condition: state
entity_id: device_tracker.paulus
state: "home"
```
`condition` can also be a list of conditions and execution will then only continue if ALL conditions return `true`.
```yaml
- alias: "Check if Paulus ishome AND temperature is below 20"
condition:
- condition: state
entity_id: "device_tracker.paulus"
state: "home"
- condition: numeric_state
entity_id: "sensor.temperature"
below: 20
```
## Wait for time to pass (delay)
Delays are useful for temporarily suspending your script and start it at a later moment. We support different syntaxes for a delay as shown below.
{% raw %}
```yaml
# Seconds
# Waits 5 seconds
- alias: "Wait 5s"
delay: 5
```
```yaml
# HH:MM
# Waits 1 hour
- delay: "01:00"
```
```yaml
# HH:MM:SS
# Waits 1.5 minutes
- delay: "00:01:30"
```
```yaml
# Supports milliseconds, seconds, minutes, hours, days
# Can be used in combination, at least one required
# Waits 1 minute
- delay:
minutes: 1
```
{% endraw %}
All forms accept templates.
{% raw %}
```yaml
# Waits however many minutes input_number.minute_delay is set to
- delay: "{{ states('input_number.minute_delay') | multiply(60) | int }}"
```
{% endraw %}
## Wait
These actions allow a script to wait for entities in the system to be in a certain state as specified by a template, or some event to happen as expressed by one or more triggers.
### Wait for a template
This action evaluates the template, and if true, the script will continue. If not, then it will wait until it is true.
The template is re-evaluated whenever an entity ID that it references changes state. If you use non-deterministic functions like `now()` in the template it will not be continuously re-evaluated, but only when an entity ID that is referenced is changed. If you need to periodically re-evaluate the template, reference a sensor from the [Time and Date](/integrations/time_date/) integration that will update minutely or daily.
{% raw %}
```yaml
# Wait until media player is stopped
- alias: "Wait until media player is stopped"
wait_template: "{{ is_state('media_player.floor', 'stop') }}"
```
{% endraw %}
### Wait for a trigger
This action can use the same triggers that are available in an automation's `trigger` section. See [Automation Trigger](/docs/automation/trigger). The script will continue whenever any of the triggers fires. All previously defined [trigger variables](/docs/automation/trigger#trigger-variables), [variables](#variables) and [script variables] are passed to the trigger.
{% raw %}
```yaml
# Wait for a custom event or light to turn on and stay on for 10 sec
- alias: "Wait for MY_EVENT or light on"
wait_for_trigger:
- platform: event
event_type: MY_EVENT
- platform: state
entity_id: light.LIGHT
to: "on"
for: 10
```
{% endraw %}
### Wait Timeout
With both types of waits it is possible to set a timeout after which the script will continue its execution if the condition/event is not satisfied. Timeout has the same syntax as `delay`, and like `delay`, also accepts templates.
{% raw %}
```yaml
# Wait for sensor to change to 'on' up to 1 minute before continuing to execute.
- wait_template: "{{ is_state('binary_sensor.entrance', 'on') }}"
timeout: "00:01:00"
```
{% endraw %}
You can also get the script to abort after the timeout by using optional `continue_on_timeout: false`.
{% raw %}
```yaml
# Wait for IFTTT event or abort after specified timeout.
- wait_for_trigger:
- platform: event
event_type: ifttt_webhook_received
event_data:
action: connected_to_network
timeout:
minutes: "{{ timeout_minutes }}"
continue_on_timeout: false
```
{% endraw %}
Without `continue_on_timeout: false` the script will always continue since the default for `continue_on_timeout` is `true`.
### Wait Variable
After each time a wait completes, either because the condition was met, the event happened, or the timeout expired, the variable `wait` will be created/updated to indicate the result.
Variable | Description
-|-
`wait.completed` | Exists only after `wait_template`. `true` if the condition was met, `false` otherwise
`wait.trigger` | Exists only after `wait_for_trigger`. Contains information about which trigger fired. (See [Available-Trigger-Data](/docs/automation/templating/#available-trigger-data).) Will be `none` if no trigger happened before timeout expired
`wait.remaining` | Timeout remaining, or `none` if a timeout was not specified
This can be used to take different actions based on whether or not the condition was met, or to use more than one wait sequentially while implementing a single timeout overall.
{% raw %}
```yaml
# Take different actions depending on if condition was met.
- wait_template: "{{ is_state('binary_sensor.door', 'on') }}"
timeout: 10
- if:
- "{{ not wait.completed }}"
then:
- service: script.door_did_not_open
else:
- service: script.turn_on
target:
entity_id:
- script.door_did_open
- script.play_fanfare
# Wait a total of 10 seconds.
- wait_template: "{{ is_state('binary_sensor.door_1', 'on') }}"
timeout: 10
continue_on_timeout: false
- service: switch.turn_on
target:
entity_id: switch.some_light
- wait_for_trigger:
- platform: state
entity_id: binary_sensor.door_2
to: "on"
for: 2
timeout: "{{ wait.remaining }}"
continue_on_timeout: false
- service: switch.turn_off
target:
entity_id: switch.some_light
```
{% endraw %}
## Fire an Event
This action allows you to fire an event. Events can be used for many things. It could trigger an automation or indicate to another integration that something is happening. For instance, in the below example it is used to create an entry in the logbook.
```yaml
- alias: "Fire LOGBOOK_ENTRY event"
event: LOGBOOK_ENTRY
event_data:
name: Paulus
message: is waking up
entity_id: device_tracker.paulus
domain: light
```
You can also use event_data to fire an event with custom data. This could be used to pass data to another script awaiting
an event trigger.
The `event_data` accepts templates.
{% raw %}
```yaml
- event: MY_EVENT
event_data:
name: myEvent
customData: "{{ myCustomVariable }}"
```
{% endraw %}
### Raise and Consume Custom Events
The following automation example shows how to raise a custom event called `event_light_state_changed` with `entity_id` as the event data. The action part could be inside a script or an automation.
```yaml
- alias: "Fire Event"
trigger:
- platform: state
entity_id: switch.kitchen
to: "on"
action:
- event: event_light_state_changed
event_data:
state: "on"
```
The following automation example shows how to capture the custom event `event_light_state_changed` with an [Event Automation Trigger](/docs/automation/trigger#event-trigger), and retrieve corresponding `entity_id` that was passed as the event trigger data, see [Available-Trigger-Data](/docs/automation/templating/#available-trigger-data) for more details.
{% raw %}
```yaml
- alias: "Capture Event"
trigger:
- platform: event
event_type: event_light_state_changed
action:
- service: notify.notify
data:
message: "kitchen light is turned {{ trigger.event.data.state }}"
```
{% endraw %}
## Repeat a Group of Actions
This action allows you to repeat a sequence of other actions. Nesting is fully supported.
There are three ways to control how many times the sequence will be run.
### Counted Repeat
This form accepts a count value. The value may be specified by a template, in which case
the template is rendered when the repeat step is reached.
{% raw %}
```yaml
script:
flash_light:
mode: restart
sequence:
- service: light.turn_on
target:
entity_id: "light.{{ light }}"
- alias: "Cycle light 'count' times"
repeat:
count: "{{ count|int * 2 - 1 }}"
sequence:
- delay: 2
- service: light.toggle
target:
entity_id: "light.{{ light }}"
flash_hallway_light:
sequence:
- alias: "Flash hallway light 3 times"
service: script.flash_light
data:
light: hallway
count: 3
```
{% endraw %}
### For each
This repeat form accepts a list of items to iterate over. The list of items
can be a pre-defined list, or a list created by a template.
The sequence is ran for each item in the list, and current item in the
iteration is available as `repeat.item`.
The following example will turn a list of lights:
{% raw %}
```yaml
repeat:
for_each:
- "living_room"
- "kitchen"
- "office"
sequence:
- service: light.turn_off
target:
entity_id: "light.{{ repeat.item }}"
```
{% endraw %}
Other types are accepted as list items, for example, each item can be a
template, or even an mapping of key/value pairs.
{% raw %}
```yaml
repeat:
for_each:
- language: English
message: Hello World
- language: Dutch
message: Hallo Wereld
sequence:
- service: notify.phone
data:
title: "Message in {{ repeat.item.language }}"
message: "{{ repeat.item.message }}!"
```
{% endraw %}
### While Loop
This form accepts a list of conditions (see [conditions page] for available options) that are evaluated _before_ each time the sequence
is run. The sequence will be run _as long as_ the condition(s) evaluate to true.
{% raw %}
```yaml
script:
do_something:
sequence:
- service: script.get_ready_for_something
- alias: "Repeat the sequence AS LONG AS the conditions are true"
repeat:
while:
- condition: state
entity_id: input_boolean.do_something
state: "on"
# Don't do it too many times
- condition: template
value_template: "{{ repeat.index <= 20 }}"
sequence:
- service: script.something
```
{% endraw %}
The `while` also accepts a [shorthand notation of a template condition][shorthand-template].
For example:
{% raw %}
```yaml
- repeat:
while: "{{ is_state('sensor.mode', 'Home') and repeat.index < 10 }}"
sequence:
- ...
```
{% endraw %}
### Repeat Until
This form accepts a list of conditions that are evaluated _after_ each time the sequence
is run. Therefore the sequence will always run at least once. The sequence will be run
_until_ the condition(s) evaluate to true.
{% raw %}
```yaml
automation:
- trigger:
- platform: state
entity_id: binary_sensor.xyz
to: "on"
condition:
- condition: state
entity_id: binary_sensor.something
state: "off"
mode: single
action:
- alias: "Repeat the sequence UNTIL the conditions are true"
repeat:
sequence:
# Run command that for some reason doesn't always work
- service: shell_command.turn_something_on
# Give it time to complete
- delay:
milliseconds: 200
until:
# Did it work?
- condition: state
entity_id: binary_sensor.something
state: "on"
```
{% endraw %}
`until` also accepts a [shorthand notation of a template condition][shorthand-template].
For example:
{% raw %}
```yaml
- repeat:
until: "{{ is_state('device_tracker.iphone', 'home') }}"
sequence:
- ...
```
{% endraw %}
### Repeat Loop Variable
A variable named `repeat` is defined within the repeat action (i.e., it is available inside `sequence`, `while` & `until`.)
It contains the following fields:
field | description
-|-
`first` | True during the first iteration of the repeat sequence
`index` | The iteration number of the loop: 1, 2, 3, ...
`last` | True during the last iteration of the repeat sequence, which is only valid for counted loops
## If-then
This action allow you to conditionally (`if`) run a sequence of actions (`then`)
and optionally supports running other sequence when the condition didn't
pass (`else`).
```yaml
script:
- if:
- alias: "If no one is home"
condition: state
entity_id: zone.home
state: 0
then:
- alias: "Then start cleaning already!"
service: vacuum.start
target:
area_id: living_room
# The `else` is fully optional and can be omitted
else:
- service: notify.notify
data:
message: "Skipped cleaning, someone is home!"
```
This action supports nesting, however, if you find yourself using nested if-then
actions in the `else` part, you may want to consider using
[choose](#choose-a-group-of-actions) instead.
## Choose a Group of Actions
This action allows you to select a sequence of other actions from a list of sequences.
Nesting is fully supported.
Each sequence is paired with a list of conditions. (See the [conditions page] for available options and how multiple conditions are handled.) The first sequence whose conditions are all true will be run.
An _optional_ `default` sequence can be included which will be run only if none of the sequences from the list are run.
An _optional_ `alias` can be added to each of the sequences, excluding the `default` sequence.
The `choose` action can be used like an "if/then/elseif/then.../else" statement. The first `conditions`/`sequence` pair is like the "if/then", and can be used just by itself. Or additional pairs can be added, each of which is like an "elif/then". And lastly, a `default` can be added, which would be like the "else."
{% raw %}
```yaml
# Example with "if", "elif" and "else"
automation:
- trigger:
- platform: state
entity_id: input_boolean.simulate
to: "on"
mode: restart
action:
- choose:
# IF morning
- conditions:
- condition: template
value_template: "{{ now().hour < 9 }}"
sequence:
- service: script.sim_morning
# ELIF day
- conditions:
- condition: template
value_template: "{{ now().hour < 18 }}"
sequence:
- service: light.turn_off
target:
entity_id: light.living_room
- service: script.sim_day
# ELSE night
default:
- service: light.turn_off
target:
entity_id: light.kitchen
- delay:
minutes: "{{ range(1, 11)|random }}"
- service: light.turn_off
target:
entity_id: all
```
{% endraw %}
`conditions` also accepts a [shorthand notation of a template condition][shorthand-template].
For example:
{% raw %}
```yaml
automation:
- trigger:
- platform: state
entity_id: input_select.home_mode
action:
- choose:
- conditions: >
{{ trigger.to_state.state == 'Home' and
is_state('binary_sensor.all_clear', 'on') }}
sequence:
- service: script.arrive_home
data:
ok: true
- conditions: >
{{ trigger.to_state.state == 'Home' and
is_state('binary_sensor.all_clear', 'off') }}
sequence:
- service: script.turn_on
target:
entity_id: script.flash_lights
- service: script.arrive_home
data:
ok: false
- conditions: "{{ trigger.to_state.state == 'Away' }}"
sequence:
- service: script.left_home
```
{% endraw %}
More `choose` can be used together. This is the case of an IF-IF.
The following example shows how a single automation can control entities that aren't related to each other but have in common the same trigger.
When the sun goes below the horizon, the `porch` and `garden` lights must turn on. If someone is watching the TV in the living room, there is a high chance that someone is in that room, therefore the living room lights have to turn on too. The same concept applies to the `studio` room.
{% raw %}
```yaml
# Example with "if" and "if"
automation:
- alias: "Turn lights on when the sun gets dim and if some room is occupied"
trigger:
- platform: numeric_state
entity_id: sun.sun
attribute: elevation
below: 4
action:
# This must always apply
- service: light.turn_on
data:
brightness: 255
color_temp: 366
target:
entity_id:
- light.porch
- light.garden
# IF a entity is ON
- choose:
- conditions:
- condition: state
entity_id: binary_sensor.livingroom_tv
state: "on"
sequence:
- service: light.turn_on
data:
brightness: 255
color_temp: 366
target:
entity_id: light.livingroom
# IF another entity not related to the previous, is ON
- choose:
- conditions:
- condition: state
entity_id: binary_sensor.studio_pc
state: "on"
sequence:
- service: light.turn_on
data:
brightness: 255
color_temp: 366
target:
entity_id: light.studio
```
{% endraw %}
## Parallelizing actions
By default, all sequences of actions in Home Assistant run sequentially. This
means the next action is started after the current action has been completed.
This is not always needed, for example, if the sequence of actions doesn't rely
on each other and order doesn't matter. For those cases, the `parallel` action
can be used to run the actions in the sequence in parallel, meaning all
the actions are started at the same time.
The following example shows sending messages out at the same time (in parallel):
```yaml
automation:
- trigger:
- platform: state
entity_id: binary_sensor.motion
to: "on"
action:
- parallel:
- service: notify.person1
data:
message: "These messages are sent at the same time!"
- service: notify.person2
data:
message: "These messages are sent at the same time!"
```
It is also possible to run a group of actions sequentially inside the parallel
actions. The example below demonstrates that:
```yaml
script:
example_script:
sequence:
- parallel:
- sequence:
- wait_for_trigger:
- platform: state
entity_id: binary_sensor.motion
to: "on"
- service: notify.person1
data:
message: "This message awaited the motion trigger"
- service: notify.person2
data:
message: "I am sent immediately and do not await the above action!"
```
<div class='note'>
Running actions in parallel can be helpful in many cases, but use it with
caution and only if you need it.
There are some caveats (see below) when using parallel actions.
While it sounds attractive to parallelize, most of the time, just the regular
sequential actions will work just fine.
</div>
Some of the caveats of running actions in parallel:
- There is no order guarantee. The actions will be started in parallel, but
there is no guarantee that they will be completed in the same order.
- If one action fails or errors, the other actions will keep running until
they too have finished or errored.
- Variables created/modified in one parallelized action are not available
in another parallelized action. Each step in a parallelized has its own scope.
## Stopping a script sequence
It is possible to halt a script sequence at any point. Using the `stop` action.
The `stop` action takes a text as input explaining the reason for halting the
sequence. This text will be logged and shows up in the automations and
script traces.
`stop` can be useful to halt a script halfway through a sequence when,
for example, a condition is not met.
```yaml
- stop: "Stop running the rest of the sequence"
```
There is also an `error` option, to indicate we are stopping because of
an unexpected error. It stops the sequence as well, but marks the automation
or script as failed to run.
```yaml
- stop: "Well, that was unexpected!"
error: true
```
## Continuing on error
By default, a sequence of actions will be halted when one of the actions in
that sequence encounters an error. The automation or script will be halted,
an error is logged, and the automation or script run is marked as errored.
Sometimes these errors are expected, for example, because you know the service
you call can be problematic at times, and it doesn't matter if it fails.
You can set `continue_on_error` for those cases on such an action.
The `continue_on_error` is available on all actions and is set to
`false`. You can set it to `true` if you'd like to continue the action
sequence, regardless of whether that action encounters an error.
The example below shows the `continue_on_error` set on the first action. If
it encounters an error; it will continue to the next action.
```yaml
- alias: "If this one fails..."
continue_on_error: true
service: notify.super_unreliable_service_provider
data:
message: "I'm going to error out..."
- alias: "This one will still run!"
service: persistent_notification.create
data:
title: "Hi there!"
message: "I'm fine..."
```
Please note that `continue_on_error` will not suppress/ignore misconfiguration
or errors that Home Assistant does not handle.
## Disabling an action
Every individual action in a sequence can be disabled, without removing it.
To do so, add `enabled: false` to the action. For example:
```yaml
# Example script with a disabled action
script:
example_script:
sequence:
# This action will not run, as it is disabled.
# The message will not be sent.
- enabled: false
alias: "Notify that the ceiling light is being turned on"
service: notify.notify
data:
message: "Turning on the ceiling light!"
# This action will run, as it is not disabled
- alias: "Turn on the ceiling light"
service: light.turn_on
target:
entity_id: light.ceiling
```
[Script integration]: /integrations/script/
[automations]: /docs/automation/action/
[Alexa/Amazon Echo]: /integrations/alexa/
[service calls page]: /docs/scripts/service-calls/
[conditions page]: /docs/scripts/conditions/
[shorthand-template]: /docs/scripts/conditions/#template-condition-shorthand-notation
[script variables]: /integrations/script/#configuration-variables