AI Decision Audit Trail

Every governed decision EVE makes can produce a record you can hand to a reviewer: what was decided (ALLOW / BLOCK / MODIFY), the reason codes, the decision identifier, and a signature that proves the record was not altered. Because the decision path is deterministic, the record is reproducible.

What the audit trail contains

• The decision — action, reason codes, and a decision identifier bound to the policy version.
• A signature — Ed25519 in production configuration (HMAC-SHA256 fallback), over a versioned canonicalization (jcs-1).
• A verifiable envelope — content hash plus signature, verifiable independently and offline.
• Determinism marker — evidence records llm_in_decision_path == false, confirming the verdict was rule-computed.

Verify a record

from eve_coreguard import verify_decision_record

report = verify_decision_record(evidence_envelope, public_key_pem=pubkey)
# report.valid == True; report.algorithm == "ed25519"; report.independently_verifiable == True

import { verifyEvidence } from "@eve/coreguard";
const report = verifyEvidence(envelope, { publicKeyPem: pubkey });
// report.valid === true, signature 'ed25519-valid'

Links

• Cryptographic details: /seo/landing/cryptographic-ai-audit-logs.md
• Evidence for reviews: /seo/landing/ai-compliance-evidence.md
• Canonicalization: /seo/landing/ai-governance-platform.md

Readiness

Signed decision evidence is SUPPORTED; offline verification in Python, Node, and the browser is SUPPORTED; jcs-1 canonicalization with cross-language byte parity is SUPPORTED. The surrounding governance decision is PILOT_READY.

Limitations

• Verification proves the evidence is authentic and unaltered; it does not attest that the underlying decision was correct.
• Independent (asymmetric) verification requires the Ed25519 public key. The HMAC-SHA256 fallback is symmetric and is not independently verifiable.
• jcs-1 is a constrained canonicalization profile; it does not serialize non-integer floats / NaN / Infinity (it fails closed). Signed governance artifacts stay within the supported value domain (for example, rates carried as integer permille).

Next step

Take a signed decision record from a pilot run and verify it yourself, offline, with the public key.