CAIN-42 CAIN StudioCCAS · Module 5 of 5 · 13 min
Evidence-backed security reviews
A security review of an agent system ends in a claim: these actions are controlled. Evidence is what makes the claim checkable by someone who does not trust you.
CAIN records each decision as canonical JSON, hashes it with SHA-256, chains it to the previous record and signs it with Ed25519. Bundles ship with a standalone verifier that imports no CAIN code.
In a review, sample decisions from the evidence, re-verify them offline, and check that the controls named in the threat model actually appear in the records.
Key points
- Claims need evidence a sceptic can re-check.
- Canonical JSON → SHA-256 chain → Ed25519.
- Verify offline with a verifier that imports no vendor code.
- Sample records against the threat model.
In the CAIN-42 codebase
keystone/family_verify.py— standalone offline verifier for evidence bundleskeystone/bundle.py— auditor ZIP export
Practice check
Practice 1 · true or false
“An evidence bundle should be verifiable without the vendor's servers.”
Practice 2 · choose one