> I stress about my agent sandboxes all the time

Same here, so I ended up moving the whole dev environment (editors, agents, containers) inside a hardened QEMU/KVM VM that reaches the internet but has no route to the host, the LAN, or any other private address. I wrote a script to create such VMs and also verify network containment by scanning outward from inside the guest. Even then, I still don't feel great when running agents unattended.

Write-up in case anyone's curious:

https://karamatli.com/posts/network-isolated-kvm-sandbox-ai-...