# @ohos.app.ability.ExtensionAbility (ExtensionAbility Base Class) **ExtensionAbility** is the base class for scenario-specific ExtensionAbilities. It is inherited from [Ability](js-apis-app-ability-ability.md), with no attribute or method added. You cannot inherit from this base class. > **NOTE** > > The initial APIs of this module are supported since API version 9. Newly added APIs will be marked with a superscript to indicate their earliest API version. > The APIs of this module can be used only in the stage model. ## Modules to Import ```ts import ExtensionAbility from '@ohos.app.ability.ExtensionAbility'; ``` **System capability**: SystemCapability.Ability.AbilityRuntime.AbilityCore