Spend Control for Email Agents
Email agents draft, send, and follow up — each send hits a paid API. A retry loop on a broken campaign is a bill in the making.
Where email agents spend
Sending APIs (SendGrid, Resend, SES) per message.
Enrichment and sequencing tools per contact.
LLM inference for drafting at scale.
The failure modes
A campaign loop re-sending the same batch multiplies per-message charges.
Unknown vendors (new sending tools) bypass procurement.
Overnight sequencing runs burn budget before review.
Which rules to start with
Daily ceiling on sending API spend.
Velocity limit on sends per window.
Merchant allowlist for approved sending vendors.
Spend map
| Email spend | Control |
|---|---|
| Sending APIs | Daily ceiling |
| Loops | Velocity limit |
| Drafting inference | Per-agent cap |
| New tools | Merchant allowlist |
FAQ
Does this slow outbound velocity?
No — ~5 ms per check; the agent keeps its pace, the budget stays enforced.
Can I cap per campaign?
Yes — per-agent rules let each campaign run its own ceiling.
Related
Stop the next $12,400 night.
One API call (or MCP tool) in front of every agent transaction — APPROVED, BLOCKED, or FLAGGED, deterministic, ~5 ms, fully logged.
See plans — from $99/mo Try a live check