What is a Kill Switch?
A kill switch is a control that instantly disables an agent's ability to spend — the emergency brake for a runaway.
How it works
One action disables spending for an agent, fleet, or merchant.
The next transaction is blocked the moment it's evaluated.
Why it matters
Runaways compound at machine speed — seconds count.
A kill switch turns 'stop the bleeding' from a project into a click.
The design principle
The kill switch should be faster than the agent. Deterministic rules make that possible.
FAQ
Does a kill switch undo past spend?
No — it stops new spend. Past transactions stay in the audit log.
Is a kill switch enough?
No — pair it with ceilings and velocity limits so you rarely need it.
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