paused panes are invisible: list_agents/read_screen report ready-idle, send_to delivers silently into them

[EtanHey]

Report (skillcreatorClaude lead, 2026-08-18 00:20Z, retro collab)

Etan: "you do know all workers are paused, right?" The lead did not and could not: list_agents showed 18 agents all ready/idle/working, blocked_on_prompt:false across the board. A paused pane and an idle pane are byte-identical in tool output; read_screen doesn't distinguish either. The lead kept dispatching into panes that would never act — this reproduces the retro's core "nothing moves and no lead knows why" symptom with zero other defects involved.

Asks

1. Detect and surface pause state (paused: true or a state value) in list_agents summaries and read_screen parsed output.
2. send_to to a paused target must warn in the receipt (or refuse) — never a clean submitted receipt into a pane that cannot act.
3. Halt escalation should treat a paused child like a halted one (ancestor notification), else pauses silently defeat feat: escalate live agent halts to ancestors #411.

• cmuxlayerClaude (lead) - claude-code/claude-fable-5