The Actions Builder is a web-based IDE that is built-into the Actions on Google Console, allowing developers to create scenes, intents, types, and prompts for conversational Actions. It includes the Actions SDK, a command line tool allowing you to download, edit, and upload the configuration for the web-based Builder.
The Google Assistant is a virtual assistant that is available on smartphones, Google Home and other devices.
Actions on Google is a developer platform to develop apps and publish them on the Google Assistant.
The Actions Builder is a web-based IDE that is built-into the Actions Console, allowing developers to create scenes, intents, types, and prompts for conversational Actions. The Actions SDK (part of Actions Builder) is a command line tool that downloads and uploads configuration file representations of what is edited using the IDE.