How to Budget for AI Agents
The honest way to budget an agent: estimate what the task legitimately costs, add headroom, and enforce the number. Here's the framework.
Estimate the legitimate cost
Work backwards from the task: tokens per run × runs per day, tool calls per task, data vendors in the path.
The incident database and eval data give reference points for what agents actually consume.
Set the ceilings
Daily ceiling ≈ legitimate daily spend × 1.5.
Per-transaction cap at the largest 'no review needed' purchase.
Approval threshold above that.
Enforce and tune
The firewall enforces the numbers; the audit log shows the real spend. Tune monthly with data — one rule change at a time.
At a glance
| Budget element | How to set it |
|---|---|
| Daily ceiling | Legit daily spend × 1.5 |
| Per-transaction cap | Largest no-review purchase |
| Approval threshold | Above the cap, wait for human |
| Merchant allowlist | Approved vendors only |
FAQ
What if I don't know legitimate spend yet?
Start conservative, watch the audit log for a week, and tune. The log is the ground truth.
Should every agent have the same budget?
No — per-agent rules let each use case run its own number.
Related
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