Spend Control for n8n
n8n automations run on schedules — which means they run at 2 AM when nobody is watching. If any step calls a paid API or triggers a payment, that's spend without oversight.
Why n8n workflows overspend
Scheduled workflows re-run automatically; a failing step retries against paid APIs.
AI-agent nodes call LLM providers per execution — cost scales with every run and every user.
A workflow that triggers a payment has no built-in approval step.
How it works
Add a sipi.bot node (HTTP Request or MCP) before any spend step in the workflow. The node evaluates the proposed transaction and the workflow branches on APPROVED / BLOCKED / FLAGGED.
Rules that fit n8n workloads
Per-transaction cap so no single run can spend big.
Daily ceiling across all workflows.
Approval threshold: big spends pause the workflow for a human.
Workflow branch logic
if decision == APPROVED: → continue to payment step
if decision == BLOCKED: → stop, log to audit trail
if decision == FLAGGED: → pause workflow, notify humanThree branches, one deterministic decision.
FAQ
Does sipi.bot run inside n8n?
sipi.bot is external — your n8n workflow calls it over HTTP or MCP like any other API. Self-hosted option available.
Can it stop a scheduled retry loop?
Yes — velocity limits cap how many transactions are allowed in a window, so a 2 AM retry loop hits the limit and stops.
What happens to the workflow when blocked?
It branches to your error path: log, notify, stop. The audit log keeps the attempt for review.
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