The Asana API is quite limiting in its ability of fetching tasks. This is especially true when fetching tasks that are not assigned to a user and a project as the endpoint to fetch tasks requires either an assignee or a project.
When adding sub tasks to a task in Asana, they are by default not assigned to a user nor to a project. In Asana they show nicely in the right pane, however via the API there is no way to get them. Or do I miss here anything?
Sorry, found it!
GET /tasks/task-id/subtasks
However, I would still be interested in an answer related to tasks without assigned user and project in general.