Least privilege
Giving each person, program and agent only the access its job needs, and no more. Then when one of them is fooled or compromised, the damage stops at what it could reach.
Broad access is the quickest way to make something work, so it's what tends to get set up, and it stays. This decides how bad a bad day gets, and it works even against attacks nobody has thought of yet.
Say it to your agent
“Give this agent a read-only database user with access to the orders table only. The CI token gets contents: read, and only the release job gets a token that can publish. Show me each permission and what breaks if it's removed.”