How should internal company agents handle credentials as their work becomes more proactive?

A user asks whether internal company agents should use fixed credentials, the credentials of whoever is using them, or a mix. They say most of their agents, including coding and outreach agents, have historically acted on behalf of users. As agents begin doing more proactive background work, the user wonders whether that approach should change, pointing to the idea of goal-driven agents that seem more like coworkers.