Remote nixos-rebuild and "--add-root" warning

I’m trying out nixos-rebuild’s remote build feature with a command like this

nixos-rebuild switch --fast --flake .#host --target-host host --build-host host --use-remote-sudo

It correctly activated the configuration, but also generated a warning:

warning: you did not specify '--add-root'; the result might be removed by the garbage collector

Is it something I should be concerned about? I don’t really understand gcroots that well, but is the warning telling me that the configuration isn’t reachable from a gcroot?