A **trait** in the SDM API comprises **fields** , **commands** , and **events**. > [!NOTE] > All calls to the SDM API should use the following endpoint: > `https://smartdevicemanagement.googleapis.com/v1` ## Fields Fields are values with common data types, such as a number or a string. For example, a field might contain a the current mode or the ambient humidity of a Google Nest Thermostat. Traits and fields can be viewed with a `GET` call to the desired API endpoint: ``` GET /enterprises/project-id/devices/device-id { "name" : "enterprises/project-id/devices/device-id", "type" : "sdm.devices.types.device-type", "traits" : { ... }, "parentRelations" : [ { "parent" : "enterprises/project-id/structures/structure-id/rooms/room-id", "displayName" : "Lobby" } ] } ``` ### Device types The `sdm.devices.types.device-type` returned by the SDM API should not be used to deduce or infer functionality of the actual device it is assigned to. There is no guarantee that a device type will remain stable for a specific device as more features are added to the SDM API. Instead, use the returned traits for the device. ### parentRelations The `parentRelations` object represents the parent resource of the current resource, either a structure or room. Display name corresponds to the `customName` field of the [Info trait](https://developers.google.com/nest/device-access/traits/structure/info) for devices with a structure parent or the [RoomInfo trait](https://developers.google.com/nest/device-access/traits/structure/room-info) for devices with a room parent. ## Commands Commands are requests associated with a trait. For example, changing the current mode or temperature setpoint on a Google Nest Thermostat. A command is sent by an `executeCommand` API call: ``` POST /enterprises/project-id/devices/device-id:executeCommand { "command" : "command-name", "params" : { "field" : "value" } } ``` Most responses to a command are a simple success or failure. See the individual trait guides for specific command usage examples. ## Events Events are asynchronous and managed by Google Cloud Pub/Sub in a single topic per Project ID. Events are sent by default for any change in the value of a trait field. They can also be sent in response to specific device actions or changes in resource assignments. See [Events](https://developers.google.com/nest/device-access/api/events) for more information. ## Trait categories ### Structure Traits [Info](https://developers.google.com/nest/device-access/traits/structure/info) `sdm.structures.traits.Info` This trait belongs to any structure for structure-related information. [RoomInfo](https://developers.google.com/nest/device-access/traits/structure/room-info) `sdm.structures.traits.RoomInfo` This trait belongs to any room for room-related information. ### Device Traits [Connectivity](https://developers.google.com/nest/device-access/traits/device/connectivity) `sdm.devices.traits.Connectivity` This trait belongs to any device that has connectivity information. [Fan](https://developers.google.com/nest/device-access/traits/device/fan) `sdm.devices.traits.Fan` This trait belongs to any device that has the system ability to control the fan. [Humidity](https://developers.google.com/nest/device-access/traits/device/humidity) `sdm.devices.traits.Humidity` This trait belongs to any device that has a sensor to measure humidity. [Info](https://developers.google.com/nest/device-access/traits/device/info) `sdm.devices.traits.Info` This trait belongs to any device for device-related information. [Settings](https://developers.google.com/nest/device-access/traits/device/settings) `sdm.devices.traits.Settings` This trait belongs to any device for device-related settings information. [Temperature](https://developers.google.com/nest/device-access/traits/device/temperature) `sdm.devices.traits.Temperature` This trait belongs to any device that has a sensor to measure temperature. ### Thermostat Traits [ThermostatEco](https://developers.google.com/nest/device-access/traits/device/thermostat-eco) `sdm.devices.traits.ThermostatEco` This trait belongs to device types of THERMOSTAT that support ECO modes. [ThermostatHvac](https://developers.google.com/nest/device-access/traits/device/thermostat-hvac) `sdm.devices.traits.ThermostatHvac` This trait belongs to device types of THERMOSTAT that can report HVAC details. [ThermostatMode](https://developers.google.com/nest/device-access/traits/device/thermostat-mode) `sdm.devices.traits.ThermostatMode` This trait belongs to device types of THERMOSTAT that support different thermostat modes. [ThermostatTemperatureSetpoint](https://developers.google.com/nest/device-access/traits/device/thermostat-temperature-setpoint) `sdm.devices.traits.ThermostatTemperatureSetpoint` This trait belongs to device types of THERMOSTAT that support setting target temperature and temperature range. ### Camera Traits [CameraClipPreview](https://developers.google.com/nest/device-access/traits/device/camera-clip-preview) `sdm.devices.traits.CameraClipPreview` This trait belongs to any device that supports the download of a clip preview. [CameraEventImage](https://developers.google.com/nest/device-access/traits/device/camera-event-image) `sdm.devices.traits.CameraEventImage` This trait belongs to any device that supports generation of images from events. [CameraImage](https://developers.google.com/nest/device-access/traits/device/camera-image) `sdm.devices.traits.CameraImage` This trait belongs to any device that supports taking images. [CameraLiveStream](https://developers.google.com/nest/device-access/traits/device/camera-live-stream) `sdm.devices.traits.CameraLiveStream` This trait belongs to any device that supports live streaming. [CameraMotion](https://developers.google.com/nest/device-access/traits/device/camera-motion) `sdm.devices.traits.CameraMotion` This trait belongs to any device that supports motion detection events. [CameraPerson](https://developers.google.com/nest/device-access/traits/device/camera-person) `sdm.devices.traits.CameraPerson` This trait belongs to any device that supports person detection events. [CameraSound](https://developers.google.com/nest/device-access/traits/device/camera-sound) `sdm.devices.traits.CameraSound` This trait belongs to any device that supports sound detection events. ### Doorbell Traits [DoorbellChime](https://developers.google.com/nest/device-access/traits/device/doorbell-chime) `sdm.devices.traits.DoorbellChime` This trait belongs to any device that supports a doorbell chime and related press events.