Text in any round that contains a tool call is NEVER delivered to the user — including text written alongside this call. To say something to the user, first send a plain-text round with no tool calls, then call `sleep` alone: a successful `sleep` call ends the run silently and delivers nothing. Call it with no arguments, never bundled with other tool calls — bundled or text-accompanied sleep calls are rejected at runtime. Sleep only when there is genuinely nothing to tell the user right now and you are waiting for the next event — a user message, the result of an async sub-agent run (analyze, or implement/research when available), or a fired alarm. The session is preserved and will be resumed automatically by the next such event; never use `sleep` to wait inside a turn.