Are the values of nodeAttrs exposed to tailscaled/tsnet?

I’m currently working on a solution that uses the tsnet Go package to communicate between some distributed agents. I saw that with the addition of NextDNS support there’s now the nodeAttrs key in the ACL policy to target particular hosts with (what appears to be) custom metadata…

Is there any way to access the nodeAttrs values via tailscale/tailscaled/tsnet or is there any proposal/plans to do so? In my usecase, and I can imagine in others too, the ability to centrally annotate (via ACL policy or similar) a host in a way you could then query on the host would be very, very useful.