CAIN-42 CAIN StudioOffline verifiers (NULLIUS)
Nullius in verba: take nobody's word for it. These are small, standalone Python programs that check CAIN-42's evidence on your own machine. They import no CAIN code, make no network calls, and say VERIFIED only when the evidence holds against keys you chose to trust.
#3 of the CAIN-42 Top 25 36/36 live checks, 3 sites 2,274 of 2,319 single-field edits refused 3 of 18 verifiers published
CAIN imports: only the Python standard library and cryptography
mission-journal edits refused
execution-truth edits refused (receipt + anchors)
Launchpad edits refused; all 45 accepted ones are documented exceptions
Why this is the pattern that matters
Every AI-security vendor publishes a dashboard. A dashboard is the vendor's word. A standalone verifier is the opposite: you download a short file, read it, run it on the evidence, and decide for yourself. If the vendor lies or the evidence is edited, the verifier says so, and the vendor cannot stop it. CAIN-42 is a Byzantine trust fabric: no component vouches for itself. This is that principle handed to the reader.
The same pattern runs through the whole Top 25: KEYSTONE's verify_keystone.py, Quorum-QaaS's
verify_qaas_receipt.py, BROKER's verifier.py, VeriCoding's certificate re-check.
See the whole family.
The three NULLIUS verifiers
| Verifier | Checks | Size |
|---|---|---|
| verify_mission_journal.py | A durable mission journal: who authorized what, what was dispatched, what effect was observed | 589 lines |
| verify_execution_truth.py | Execution-truth receipts: did exactly the authorized effects occur, as seen by independent sensors | 464 lines |
| verify_launchpad.py | A deployment export: every effect traced to an authorized step, signed gate ledger, witness quorum | 733 lines |
On this site
How it works
Pinning, re-derivation, exit codes.
The three verifiers
What each one checks, in detail.
Live demo
Hash the verifiers in your own browser.
Evidence
The 2,319-edit sweep, field by field.
Verify it yourself
Every command.
The verifier family
Every standalone verifier in CAIN-42.
The 10-27 audit
Four real bugs we found and fixed.
Limits
What VERIFIED does not mean.
Use cases
Who runs these, and why.
2026-11-02 upgrade
The sweep kit.
History
Releases and fixes.
FAQ
Common questions.
FIRME AI CORPORATION · CAIN-42 is a Byzantine trust fabric. Numbers marked "our own check" were run by us, not by an independent party. Nothing on these pages is a certification.