I have a smart speaker with buit-in Google Assistant which I want to automatically make announcements at specific times. The times are determined by a program I wrote running in the cloud which can send HTTP POST requests at those times (e.g. to trigger a Telegram bot or anything else with a usable API).
Is there a way to send POST requests directly to my smart speaker with a message to announce? Or would I need some intermediary app/service to integrate with Google Assistant?