claude code agent gets around writing access by bash commands

If I understand correctly, the point of isolating bash commands vs. writing is for them to have execution tools. however agents with bash access can get around writing by command line commands. what's a good way to handle it? and because agent can run bash commands once they have the tools, file editing is no longer supervised.
also I am having issue set up "conductor agent" to work with other agents and go back and force to recursively solve issues, since there is no hard handoff mechanism.
what are the best way to use agents in general?