Generic Controller Interfaces

Generic controllers are general-purpose interfaces that you can use to model different components of a smart home device in your smart home add-ons. For more details, see Connect Your Device Cloud with Smart Home Add-ons. The following list shows the generic controller interfaces:

• Alexa.DataController – Support retrieval and deletion of customer data.
• Alexa.ModeController – Model properties of a device that the user can set to one of a list of values.
• Alexa.RangeController – Model properties of a device that the user can set to one of a range of values.
• Alexa.SimpleEventSource – Model stateless events on a device, such as a button press on a remote switch or smart button device. Users can connect the events to Alexa Routines.
• Alexa.ToggleController – Model properties of a device that the user can set to on or off.

Choose the most specific controller available to model components of your devices, because the more specific the controller, the more natural the utterances are for your user. However, the generic controllers allow you to support functions that might not be available by default with more specific controllers, such as the ability to implement multiple instances of a controller for a single device, and support for semantics.

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Correspondence of specific and generic controllers

The following table lists the generic controllers, and examples of corresponding specific controllers, that you can use to model components of your devices.

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Multiple instances

When you implement a specific controller interface in the smart home add-on for your device, you can only implement one instance of the interface. When you implement a generic controller interface in your add-on, you can implement multiple instances of the controller. You specify an instance name for each instance of the controller in the discovery response for your add-on. For details and sample code, see the documentation for each generic interface. The following scenarios are examples of implementing multiple instances of generic controllers:

• For a washing machine device, implement one instance of the Alexa.ModeController interface named Washer.WashCycle to model the wash cycle. Implement a second instance of the Alexa.ModeController interface named Washer.WashTemperature to model the water temperature.
• For a ceiling fan with a light, implement one instance of the Alexa.RangeController interface named Fan.Speed to model the fan speed. Implement a second instance of the Alexa.RangeController interface named Fan.Light to model the brightness of the light.
• For a stove with a cooktop and an oven, implement one instance of the Alexa.ToggleController interface named Oven.Light to model the oven light. Implement a second instance of the Alexa.ToggleController interface named Stovetop.ResidualHeat to model the safety feature that warns users when there is residual heat and the cooktop is too hot to touch.
• For a remote switch with three buttons, implement one instance of the Alexa.SimpleEventSource interface for each button and define one or more events per button.

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Utterances

Both specific and generic controllers use a pre-built voice-interaction model, which means that when you use them, the utterances that users say to Alexa are already defined for you. Usually you choose the most specific controller available to model components of your devices, because the more specific the controller, the more natural the utterances are for your user. The following table compares utterances for generic controllers and specific controllers. In these examples, a generic controller is used for the same device as a specific controller. For the generic controllers, the user must say the name of the instance, or a friendly name replacement for it, in the utterance.

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Semantics

Use semantics to enable additional features, such as additional user utterances and notifications when your device requires attention. To use semantics, include a semantics object in your discovery response.

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Semantics for user utterances

When you implement generic controllers you can optionally enable additional utterances for your users by using semantics. When you use semantics, you manually map the phrases , , , and to the directives of your controller. For example, if you have a Alexa.ToggleController for a garbage can lid, you can map the phrase to the TurnOn directive. For details and sample code, see the documentation for each generic interface. The following examples show some user utterances that use semantics:

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Semantics for Alexa hunches

You can use semantics to enable Alexa hunches for your device to conserve energy on behalf of users. For details about hunches, see What Are Alexa Hunches? and Enable Alexa to Proactively Act on Hunches Without Customers Needing to Ask. The semantics for Alexa hunches are Alexa.Actions.SetEcoOn, Alexa.Actions.SetEcoOff, Alexa.States.EcoOn, and Alexa.States.EcoOff. For an example discovery response that includes support for Alexa hunches, see discovery response example for a water heater.

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Semantics for announcements

You can use semantics to enable announcement to the user when your device requires attention. For example, Alexa can notify a user when their washing machine cycle has completed, or when their automatic vacuum cleaner gets stuck. Before Alexa begins to send announcements to the user, the customer must opt-in to announcement notifications in the Alexa app. To enable semantics for announcements, you map the state of your device to one of the Alexa states in your discovery response. For more details about announcements and announcement format, see ProactiveNotificationSource.

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Restrictions

The following restrictions apply to add-ons that use generic controllers:

• You can’t use generic controllers to control devices that belong to a Smart Home Device Group.
• If you use semantics for user utterances, each semantic phrase must be unique across all controller instances in your add-on.

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Related topics

• Alexa.Discovery
• Friendly Name Resources and Assets