Short answer: You can get subscriber lists in Acumbamail by hand from its own interface, but it won’t repeat itself. On TinyCommand, add the Acumbamail Get Subscriber Lists action to a workflow, map its 0 inputs from any upstream app, and it runs automatically every time the trigger fires. No code, and a free tier to start.
{}
{"12345": {"name": "Newsletter","description": "Main list"}}
Use these fields in downstream nodes for routing, logging, or error handling.
Any of these apps can fire this action as part of a workflow.