> For the complete documentation index, see [llms.txt](https://modeltrainscript.gitbook.io/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://modeltrainscript.gitbook.io/docs/manual/automation/flags.md).

# Flags

Flags allow you to make your scripts more reusable and dynamic. A flag is a simple on/off switch that can be checked in conditions within scripts, sections, or actions.

A typical use case is enabling or disabling sounds for late-night running sessions — create a "Sound" flag and use it as a condition on all sound-related actions.

## Creating flags

Flags can be created from the [profile](/docs/manual/profile.md) screen under the automation section. Each flag has a name and an optional default state (enabled or disabled at startup). You can also configure whether the flag appears in the throttle for quick toggling.

## Scoping

For fine-grained control, flags can be active at three levels. During evaluation, if a flag is active at **any** of these levels, the condition is evaluated as true.

### Global

When you enable or disable flags in the throttle (under the automate tab), you do so at the **global** scope — these flags are active for all scripts.

### Script

With the [set flags](/docs/manual/automation/scripts/action/structure.md#set-flags) action, you can activate specific flags within your script. These flags are only active for that specific script run. Setting script-level flags replaces any previously set flags at this level.

### Vehicle

You can enable flags on a specific [vehicle](/docs/manual/vehicles.md). These flags become active when that vehicle is selected in a script — via the [select vehicle](/docs/manual/automation/scripts/action/vehicle-control.md#select) action, the "select active vehicle" option of an execution event, or the [select from feedback](/docs/manual/automation/scripts/action/vehicle-control.md#select-feedback) action. As soon as another vehicle is selected, the previous vehicle's flags are no longer active.

{% hint style="info" %}
Once a flag is active at any level, it cannot be disabled from another level. For example, if a flag is enabled globally, a script cannot disable it by omitting it from the script-level flags.
{% endhint %}

## Using flags

Flags can be used in three places:

* **Conditions** — On actions, sections, or scripts. Check whether a flag is enabled or disabled.
* **Execution events** — Not directly, but conditions on event-triggered scripts can check flag state.
* **Vehicle profiles** — Combine flags with vehicle-specific behaviour to create context-dependent automation.