diff --git a/nix/modules/hive-c0re.nix b/nix/modules/hive-c0re.nix
index 28400266..7b89f221 100644
--- a/nix/modules/hive-c0re.nix
+++ b/nix/modules/hive-c0re.nix
@@ -162,8 +162,9 @@ in
               WireGuard mesh. Used as the `allowedIPs` for the peer's
               WireGuard config entry and injected into `HYPERHIVE_PEERS`
               so hive-c0re can route intra-swarm traffic to the mesh
-              address rather than the public domain. Required when
-              `wireguardPublicKey` is set.
+              address rather than the public domain. Required to include
+              the peer in the WireGuard mesh (peers missing this field
+              are silently excluded from `wg-hive`).
             '';
           };
         };
@@ -218,6 +219,7 @@ in
 
     address = lib.mkOption {
       type = lib.types.str;
+      default = "";
       example = "10.100.0.1/24";
       description = ''
         IP address (with prefix) of this host on the WireGuard mesh.