The Alexa Voice Service (AVS) API allows developers to voice-enable connected products with a microphone and speaker. Once integrated, your product will have access to the built in capabilities of Alexa (like music playback, timers and alarms, package tracking, movie listings, calendar management, and more) and third-party skills developed using the Alexa Skills Kit.
AVS is comprised of interfaces that correspond to client-functionality, like speech recognition, audio playback, and volume control. Each interface contains logically grouped messages called directives and events. Directives are messages sent from the cloud instructing your client to take action. Events are messages sent from your client to the cloud notifying Alexa something has occurred.
The API uses Login with Amazon (LWA) for product authorization and exposes an HTTP/2 endpoint.