Subagents & Agent Teams

🤖 Subagents & Agent Teams

One agent hits a wall; many agents don't. The harness runs two delegation models — lightweight subagents and durable Agent Teams.

Subagents — fire-and-delegate

subagent spawns a fresh child agent with its own context window. The child does the work and returns only the result — intermediate steps never pollute the parent's context.

• Continuable (subagent) — the child can be messaged later, resumed, interrupted. Omitted calls default to background with automatic result delivery.
• One-shot (subagent_fork) — run it, collect it, forget it. Defaults to foreground.
• run_in_background: true returns a job id immediately; collect with job_output, stop with job_kill.
• Drive live children with send_message, interrupt_agent, list_agents; the child hands results back with report.

When to delegate: scoped research, an isolated analysis, a file sweep — anything self-contained enough to be described in one standalone prompt. The child does not see the parent conversation, so give it everything it needs.

Agent Teams (experimental) — durable crew

Teams are a different animal: a Lead keeps a durable journal of membership, messages, acknowledgements, and tasks; teammates are resumable children that survive process restarts.

Piece	What it gives you
spawn_teammate	Create a durable named teammate with its own session.
send_message	Send a peer message; delivery is durable — queued, checkpointed, retried on recovery.
Delivery modes	quiet (drop into the target's session silently) vs wakeup (wake the target and surface it).
wait_agent	Block until the next Team change (bounded 10s–1h, cancellable).
followup_task / interrupt_agent	Lead-only control over teammate rounds.
Task board	team_task_create / get / list / update with compare-and-set updates — no lost writes between teammates.

Why it matters for engagements: run a lead coordinating five scoped hunters — one on subdomains, one on JS secrets, one on the API surface — each with durable inboxes and a shared task board, all inside one harness instance. If the process dies, sessions and mailbox state persist and recover.

Enable it: the shipped base bundle keeps Agent Teams disabled; add the Agent Teams profile patch to enable it (and disable the legacy control names at the same time).

Choosing a shape

	Subagent	Agent Team
Lifetime	One task	Survives restarts
Communication	Result return + messages	Durable mailbox + task board
Coordination	Parent-driven	Lead + journal
Best for	Scoped delegation	Parallel crews over long engagements