- agent_run gains depth / spawn_reason (0029); agent_run_event types
subagent_spawned / subagent_event / subagent_completed
- agent.spawn (propose, medium, replay never): allowlist ⊆ parent, mode not
above parent, budget carved from parent's remainder, idempotent per run+input;
settings.pi.subagents {enabled, maxConcurrent, maxDepth} (subagentsEnabled kept as alias)
- child runs claim a concurrency slot under an advisory lock (waitForFact while
queued); agent.await polls business tables without calling the model
- parent abort cascades to all descendants; parent runtime budget counts
descendant usage; child events mirrored into the parent stream by parent seq
- authorize caps every child call by all ancestors' allowlists/kinds
- session page shows parent link, inherited info and the subagent tree
- e2e E11; runbook section on subagents
Co-Authored-By: Claude Opus 5.5 <[email protected]>
