Possible to apply container label to all containers started through the proxy?

Hey folks, is it possible for the docker-socket-proxy to mutate requests as it proxies them? I'm hoping that I can mutate requests to create containers by adding an additional container label. That way it's easy to query/search for containers on the host that were started via a particular proxy instance.

My use-case is that we have an application that may start/stop docker containers during its normal operation, but we want to be able to detect/mitigate container leaks (this application may forget it started a docker container or it may terminate before cleaning these containers up). I'm hoping that we can run an instance of docker-socker-proxy with a hook that adds a label to all container creations. This would effectively namespace the containers started by our application so they can be monitored programmatically.

Start by locating how this proxy handles Docker container-creation requests and whether it supports request mutation or hooks. Determine whether adding a label to every container created through one proxy instance is feasible without affecting other requests. Done means the behavior is implemented, documented, and covered by tests for labeled container creation.