{
  "experiment": "4-4",
  "authority": "book/chapter4.md:319",
  "subagent_primitives": ["spawn_subagent", "send_message_to_subagent", "cancel_subagent", "get_subagent_status"],
  "modes": ["sync", "async"],
  "context_strategies": ["minimal", "llm_generated"],
  "human_tools": ["request_human_approval", "request_human_input"],
  "human_requirements": ["timeout", "conservative_default", "active_confirmation"],
  "notification_channels": ["im", "email", "slack"],
  "completion_rule": "All lifecycle, context, HITL, timeout, and real multi-channel notification gates must pass. Missing channel credentials is blocked, not simulated."
}