diff --git a/nip29/group.go b/nip29/group.go
index dc33b40..b635b00 100644
--- a/nip29/group.go
+++ b/nip29/group.go
@@ -45,10 +45,11 @@ type Group struct {
 	LastMembersUpdate  nostr.Timestamp
 }
 
-func NewGroup(id string) (Group, error) {
-	gad, err := ParseGroupAddress(id)
+// NewGroup takes a group address in the form "<id>'<relay-hostname>"
+func NewGroup(gadstr string) (Group, error) {
+	gad, err := ParseGroupAddress(gadstr)
 	if err != nil {
-		return Group{}, fmt.Errorf("invalid group id '%s': %w", id, err)
+		return Group{}, fmt.Errorf("invalid group id '%s': %w", gadstr, err)
 	}
 
 	return Group{
diff --git a/nip29/nip29_test.go b/nip29/nip29_test.go
index 4950aeb..1b8cf8f 100644
--- a/nip29/nip29_test.go
+++ b/nip29/nip29_test.go
@@ -12,17 +12,17 @@ const (
 )
 
 func TestGroupEventBackAndForth(t *testing.T) {
-	group1, _ := NewGroup("xyz")
+	group1, _ := NewGroup("xyz'relay.com")
 	group1.Name = "banana"
 	group1.Private = true
 	meta1 := group1.ToMetadataEvent()
 	if meta1.Tags.GetD() != "xyz" ||
 		meta1.Tags.GetFirst([]string{"name", "banana"}) == nil ||
 		meta1.Tags.GetFirst([]string{"private"}) == nil {
-		t.Fatalf("translation of group1 to meta1data event failed")
+		t.Fatalf("translation of group1 to metadata event failed: %s", meta1)
 	}
 
-	group2, _ := NewGroup("abc")
+	group2, _ := NewGroup("abc'groups.com")
 	group2.Members[ALICE] = &Role{Name: "nada", Permissions: map[Permission]struct{}{PermAddUser: {}}}
 	group2.Members[BOB] = &Role{Name: "nada", Permissions: map[Permission]struct{}{PermEditMetadata: {}}}
 	group2.Members[CAROL] = EmptyRole