I know my question maybe too broad, but as someone who's planning to stay in academia, I want to ask anyone who is supervising PhD students about how you contribute to their papers in order to be included as authors.
Do you just need to discuss the problem (e.g what is it? Is it feasible or worth to be solved), point them to potential directions and review the drafts? You can also help writing other sections which don't directly involve in solving the problem such as: introduction, motivation or conclusion. This is the approach that my supervisor and most lecturers in my department are taking.
Or, do you have to directly take part in solving the problem such as analysing it, designing system, performing experiments and evaluating results?