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What is a Subagent?

A subagent is a child agent spawned by a coordinator to complete a subtask. Subagents make spend compound: fan-out multiplies every cost.

How subagents work

A coordinator decomposes a task and spawns subagents in parallel.

Each subagent makes its own tool calls — and its own purchases.

Why subagents change the spend math

Cost compounds: N subagents × their retries and tool calls.

No single subagent looks expensive; the fleet does.

The control

Shared daily ceilings and velocity limits across the coordinator's agents stop fleet-wide compounding.

FAQ

How do I budget for subagent fleets?

Scope rules to the coordinator's agents so the whole fleet shares one ceiling.

What's the biggest subagent risk?

Compounding — many agents retrying the same failure in parallel.

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