You can automatically add listeners who sign up via ThriveCart using a Hello Audio behavior rule in ThriveCart. This will work for Learn/Learn+ courses as well since they'll be signing up through a ThriveCart checkout page.
Head to your integrations page in Hello Audio and find ThriveCart Custom HTML. Click "Create custom actions." If it's not there, create a API key first by clicking "Generate".
Choose your feed and then decide what you'd like ThriveCart to do when the action is fired.
Add/Update Listeners - Will add a new listener, or add name/tag information to an existing listener.
Delete Listeners - Will block and remove the listener completely from the feed in Hello Audio
Block Listeners - Will prevent the listener from being able to listen to the feed, but will still be visible in your Hello Audio account.
When adding or updating a listener, you can decide if you'd like to send the invitation email, include their names in your Hello Audio account, or tag them.
Make your selections for those options and click "Copy HTML".
Setting Up Your ThriveCart Product
Edit your product in ThriveCart and click "Behavior", then "+ Add rule".
Choose what you'd like to start the rule, e.g. "When the main product is purchased," and then select "Custom HTML". Paste the copied HTML from Hello Audio into that box and click "Save" then "Save & get URL" for the product changes to go into effect. Done!