Automatically grant file access permissions

[YTG1234]

I run Jellyfin as a launchd agent, adapted code:

launchd.user.agents.jellyfin = {
  path = [ pkgs.jellyfin ];
  command = pkgs.writeShellScript "jellyfin-service" ''
    exec ${pkgs.lib.getExe pkgs.jellyfin} --service -d $HOME/.local/share/jellyfin -c $HOME/.config/jellyfin -C $HOME/.cache/jellyfin
  '';
  serviceConfig.KeepAlive = true;
  serviceConfig.RunAtLoad = true;
};

My libraries live on an external drive, and macOS apps need extra permissions for that. My problems are two:

1. macOS doesn't show the pop-up at all, so I just get System.IO.IOException: Operation not permitted errors.
2. Even if the pop-up were to show up, I would still prefer to grant the permissions preemptively, perhaps during activation.

How should I go about this?

---

Note: this isn't just a standard Unix permission error. The relevant files have read permission for everyone (mode 644).

[Samasaur1]

I think problem 1 would be solved by manually running the executable from a terminal?

[YTG1234]

This is very weird… Running the generated script from the terminal works, but the launchd service is still denied access.

[Samasaur1]

Have you tried restarting after running the script manually?

[YTG1234]

I have, it still doesn't work.

[YTG1234]

Any other ideas?