Handover
Budget envelope
A budget envelope is a set of limits on time, spend, and how many parallel agents a run may use, declared before the run starts along with the behavior at the ceiling.
Control sits with the person
When to use it
Any long-running or multi-agent task, and any product where the cost of a run varies by an order of magnitude depending on how the agent interprets the request.
What it prevents
Runaway fan-out and unexplained cost. Anthropic reported having to teach its lead research agent explicit effort-scaling rules to stop it spawning dozens of subagents for simple questions.
Run budgetset before starting
Wall clock20 min ceiling
Parallel agents3 of 5
Tool calls120 ceiling
At the ceiling: stop and report, rather than ask for more.
Who ships it
- Effort selectors in the mainstream assistants
- Enterprise model gateways: per-team budgets
Sources
Related patterns: Autonomy dial · Orchestrator and workers