Add btd_error_agent_not_available()
diff --git a/audio/gateway.c b/audio/gateway.c
index 655047d..43a4b02 100644
--- a/audio/gateway.c
+++ b/audio/gateway.c
@@ -369,8 +369,7 @@
 	int err;
 
 	if (!gw->agent)
-		return g_dbus_create_error(msg, ERROR_INTERFACE
-				".Failed", "Agent not assigned");
+		return btd_error_agent_not_available(msg);
 
 	err = get_records(au_dev);
 	if (err < 0)
diff --git a/src/adapter.c b/src/adapter.c
index 2ff59a0..a36d2b1 100644
--- a/src/adapter.c
+++ b/src/adapter.c
@@ -1412,8 +1412,7 @@
 	int err;
 
 	if (!adapter->agent)
-		return g_dbus_create_error(msg, ERROR_INTERFACE ".Failed",
-						"No agent registered");
+		return btd_error_agent_not_available(msg);
 
 	if (!adapter->mode_sessions)
 		adapter->global_mode = adapter->mode;
diff --git a/src/error.c b/src/error.c
index 1ee98c8..ebfc614 100644
--- a/src/error.c
+++ b/src/error.c
@@ -97,6 +97,12 @@
 					"No such adapter");
 }
 
+DBusMessage *btd_error_agent_not_available(DBusMessage *msg)
+{
+	return g_dbus_create_error(msg, ERROR_INTERFACE ".AgentNotAvailable",
+					"Agent Not Available");
+}
+
 DBusMessage *btd_error_failed(DBusMessage *msg, const char *str)
 {
 	return g_dbus_create_error(msg, ERROR_INTERFACE
diff --git a/src/error.h b/src/error.h
index f346c07..ffd4332 100644
--- a/src/error.h
+++ b/src/error.h
@@ -38,4 +38,5 @@
 DBusMessage *btd_error_does_not_exist(DBusMessage *msg);
 DBusMessage *btd_error_not_authorized(DBusMessage *msg);
 DBusMessage *btd_error_no_such_adapter(DBusMessage *msg);
+DBusMessage *btd_error_agent_not_available(DBusMessage *msg);
 DBusMessage *btd_error_failed(DBusMessage *msg, const char *str);