Agents should have direct and exclusive access to certain areas to the coupled model entities. Some companies have implemented frameworks to avoid this, which just slows down the model access and yet still can be worked around without much effort.
Many OO languages have friend classes. This will let you define the Agent to be the friend of its coupled Database entity to be friends (e.g. Account and AccountAgent). Only the AccountAgent class can call/access protected Account elements outside the database entity.
It would be nice to see this in Jade. Also to be considered is being able to declare items as private (accessible to self only.)