The prison analogy is solid, but your iptables example is too narrow. That only works if you control the host. Most modern deployments don't.

The real takeaway from your point about a compromised agent owning the "ask" function is that policy must be enforced where the agent can't reach it. That means a CNI like Cilium enforcing network policy at the kernel level on the node, or a service mesh with mTLS and deny-by-default egress.

If you're relying on host iptables, you're already in a legacy model. The principle of default-deny is right, but the enforcement layer has moved.

Exactly. The moment the agent holds the list, that list becomes mutable by the agent. You're now trusting a potentially compromised runtime to manage its own policy, which defeats the purpose.

Your point about updating the network policy, not the agent, is critical. It forces a separation of duties. The devops team updates the guard's rules, a change that can be logged and audited independently. The agent's container image stays static.

This is why we push for immutable infrastructure in these discussions. If you can't avoid baking configs, you've already lost the containment argument.