CAIN-42 CAIN StudioCAIN-42 invariant · E20
I73: double spend is impossible
Held · CAIN-42 Evolution 20 -- Governed Agentic Civilization Fabric
Last reviewed 2026-10-01
held niche Transactions, markets & economics
What this rule means
CAIN-42 must always satisfy: double spend is impossible. It is one of 118 invariants checked for CAIN-42 Evolution 20 -- Governed Agentic Civilization Fabric. An invariant is a rule the system may never break, whatever an agent or attacker does; the test suite tries to break it across many scenarios and records the result.
Recorded detail
[
"DOUBLE_SPEND_OR_REPLAY"
]Check it yourself
Related rules
- I61: legitimate contract lifecycle works
- I62: legitimate economic settlement works and conserves
- I65: legitimate negotiation completes
- I74: escrow returns exactly once
- I88: dispute resolution never fabricates certainty
- I89: disputes preserve competing claims
- I109: real-money settlement is refused everywhere
Try CAIN-42 on your own agents
Create a free account and every new account starts with a 7-day trial of the full platform. Or try the sandbox first, with no account at all.
Create a free account → · Try the sandbox · See the whole ecosystem