--- description: Docker extension API reference keywords: Docker, extensions, sdk, API, reference skip_read_time: true --- # Interface: Extension **`Since`** 0.2.0 ## Properties ### vm • `Optional` `Readonly` **vm**: [`ExtensionVM`](ExtensionVM.md) ___ ### host • `Optional` `Readonly` **host**: [`ExtensionHost`](ExtensionHost.md) ___ ### image • `Readonly` **image**: `string` **`Since`** 0.3.3