+The root manages source routes with ``route(source, agent)``,
+``unroute(source)``, and ``routes()``, only after the user agrees. A
+source is ``whatsapp:CHAT-ID``, with the ID from ``whatsapp_find`` or a
+``[WhatsApp]`` message, and the agent must be its child. The root keeps
+the map in ``agent/routes.json`` with mode 0600. Children and subagents
+have no route tools. There is no command to change routes. Each routed
+batch enters only its child's log and wakes it, including a group batch
+with no mention. The durable agent queue prevents a second log entry
+after a restart. An unrouted source or a missing child uses the root. A
+queued batch whose child is removed while stopped goes to the root.
+