Hello,
Is this document you are looking for? https://learn.microsoft.com/en-us/microsoftteams/platform/task-modules-and-cards/cards/universal-actions-for-adaptive-cards/overview?tabs=mobile#universal-actions
Before the Universal Actions for Adaptive Cards, different hosts provided different action models as follows:
Teams or bots used Action.Submit, an approach which defers the actual communication model to the underlying channel.
Outlook used Action.Http to communicate with the backend service explicitly specified in the Adaptive Card payload.
More information please refer to the document.
Regards,
Yutong