Add never called overrides with exception for clarity.

src/main/java/li/cil/oc2/common/bus/device/rpc/RPCDeviceList.java

@@ -2,6 +2,7 @@ package li.cil.oc2.common.bus.device.rpc;
 
 import li.cil.oc2.api.bus.device.rpc.RPCDevice;
 import li.cil.oc2.api.bus.device.rpc.RPCMethod;
+import net.minecraft.nbt.CompoundTag;
 
 import java.util.ArrayList;
 import java.util.Collection;
@@ -46,4 +47,17 @@ public record RPCDeviceList(ArrayList<RPCDevice> devices) implements RPCDevice {
             device.suspend();
         }
     }
+
+    // NB: We only use the list device in the adapter, for referencing grouped devices by their ID.
+    //     As such, serialize/deserialize will never be called on this class.
+
+    @Override
+    public CompoundTag serializeNBT() {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public void deserializeNBT(final CompoundTag tag) {
+        throw new UnsupportedOperationException();
+    }
 }