A team of agents — delegation, hand-off, a graph, and a budget

How it works

A supervisor briefs a researcher, hands what comes back to a writer, and stops for a person before publishing. Every box above is a process; the four ways agents are usually wired together are all just process code here.

Delegation — the tool is another agent

A tool call is call(), and an agent is a process, so delegating is calling. d.call journals it on the caller's side and derives an idempotency key, which the callee uses to recognise a retry:

const notes = await d.call('research', (callId) =>
  crew.researcher.call({ type: 'research', topic: msg.topic, callId }))

Press kill the supervisor while it is writing. The supervisor dies with its brief unacknowledged, the next lookup activates a new one, and the brief is replayed — but the researcher's run count does not move, because the delegated call is answered from its record. That is the difference between a durable process and a process that merely saves its state.

Hand-off — the output is the next input

No shared blackboard and no message-history object: what the researcher returned is passed to the writer as an argument, and both are visible in the supervisor's state because that is where they were put.

The graph is the state

There is no graph library. stage is a field, the code between yields is the edge, and the row of nodes above is an ordinary view of it — which means the pipeline's position survives a restart along with everything else.

s = { ...s, stage: 'writing', notes }
yield s

Usage limits — one process everybody has to ask

The budget is a plain, non-durable process: a live limit for this deployment rather than a record of what happened. Each agent asks it before spending, inside a d.step so a replay does not spend twice. Set the limit low enough and the pipeline stops at out of budget instead of half-finishing.

const allowance = await d.step('budget', () => meter.call({ type: 'spend', tokens: 200 }))

The tests (multi-agent.test.ts) drive all four patterns headlessly, including the kill: no DOM, no network, no mocking framework.