EchtPost Postcards EchtPost Postcards is a service that lets users create and send personalized physical postcards directly from their computer or phone. It's used by individuals and businesses who want to send unique, tangible communications to recipients worldwide. Official docs: https://www.echtpost.de/api/ EchtPost Postcards Overview - Postcard - Recipient - Address Book - Contact Use action names and parameters as needed. Working with EchtPost Postcards This skill uses the Membrane CLI to interact with EchtPost Postcards. Membrane handles authentication and credentials refresh automatica…