diff --git a/ref-filter.c b/ref-filter.c
index 9bf92db6df..4f4591cad0 100644
--- a/ref-filter.c
+++ b/ref-filter.c
@@ -372,11 +372,11 @@ static int objectname_atom_parser(const struct ref_format *format, struct used_a
 		atom->u.objectname.option = O_LENGTH;
 		if (strtoul_ui(arg, 10, &atom->u.objectname.length) ||
 		    atom->u.objectname.length == 0)
-			return strbuf_addf_ret(err, -1, _("positive value expected objectname:short=%s"), arg);
+			return strbuf_addf_ret(err, -1, _("positive value expected '%s' in %%(%s)"), arg, atom->name);
 		if (atom->u.objectname.length < MINIMUM_ABBREV)
 			atom->u.objectname.length = MINIMUM_ABBREV;
 	} else
-		return strbuf_addf_ret(err, -1, _("unrecognized %%(objectname) argument: %s"), arg);
+		return strbuf_addf_ret(err, -1, _("unrecognized argument '%s' in %%(%s)"), arg, atom->name);
 	return 0;
 }