product · ledger
Ledger
The evidence layer. Every agent action captured, signed, stored, and exported in a form your auditor accepts.
An auditor can't use a JSON log. Ledger turns agent activity into evidence — each event signed with your key at execution, chained by AGT, retained up to seven years, exported as a PDF mapped to the controls your regulator names.
install
Three lines. Events flowing.
The wrapper installs beside Microsoft AGT and hooks its audit log the moment init() returns. Existing AGT instrumentation is untouched.
pip install wytness-aiimport wytness_ai wytness_ai.init(pii_fields=["customer.email"])Prefer zero Wytness code on your runtime? Point AGT's CloudEvents sink at /ingest — see Built on AGT.
what's inside
Six guarantees, one surface.
per-event signing
Ed25519 with a customer-held key. Verifiable event by event, not just chain by chain.
customer-held pii keys
Generated in your browser; we receive tokens we can't decrypt.
chain verification
AGT's hash chain, surfaced in the dashboard and bundled into every export.
seven-year retention
Append-only Azure Blob with a soft-delete recovery window; on cancellation, your history is handed over as signed Evidence Packs.
bring your own storage
Business and up: raw events land in your tenancy; we keep a metadata index only.
evidence packs
Printable reports and signed, dated JSON downloads mapped to SOC 2, the EU AI Act, and ISO 27001.
subsection · signing
How signing works
AGT's hash chain proves the record wasn't altered. The Wytness envelope proves who attested to it. Before an event leaves your environment, PII fields become HMAC tokens and the event is signed with your Ed25519 key; our ingest verifies against your registered public key and rejects anything that doesn't match.
Hand your auditor an Evidence Pack and they verify it offline — chain hashes, per-event signatures, public keys — with no Wytness account and no access to our systems. Every event your SDK signed ships the exact bytes its signature covers, so the check is theirs to run, not ours to vouch for. When your DPO asks who can see the data, the answer is: you. We'll put that in the DPA and prove it cryptographically.
event · crypto
agt_merkle_root_hash sha256:c4fc71af… wytness_envelope_sig ed25519:MEUCIQDGx…
CHAIN LINK ✓ · VERIFIED ✓ · offline, with your public key
subsection · storage
Bring Your Own Storage
On Business and Enterprise, raw events write to your Azure Blob in your tenancy — with your own immutability policy if you enable it. Wytness keeps only the metadata index that renders the dashboard. Anything that's evidence lives with you.
| In Wytness | In your storage | |
|---|---|---|
| Raw audit events | — | ✓ |
| Pseudonymised PII tokens | (for query) | (in events) |
| Event signatures | (for verify) | (in events) |
| Event metadata index | ✓ | ✓ |
| Anomaly findings + approvals | ✓ | — |
| Dashboard state, users, RBAC | ✓ | — |
7 yr
default retention — bump to 10 for EU AI Act high-risk
0
added round-trips — your bucket and our index fan out in parallel
5 min
read-through cache on event clicks
$0
egress in normal operation — you pay your cloud's storage bill directly
subsection · exports
Evidence Packs
Generated on demand: executive summary, control-by-control framework mapping, sampled events with their signatures, chain attestation, and an honest methodology-and-limitations section. Download it as a signed, dated JSON pack — sealed with the Wytness key, carrying the signed bytes and the public keys, so it verifies offline — or print it for the file.
At launch: EU AI Act (Articles 12, 13, 15) · SOC 2 Type II · ISO 27001. GDPR Article 30 and HIPAA follow Q3 2026.
availability
What each tier gets
| Starter | Growth | Business | Enterprise | |
|---|---|---|---|---|
| AGT ingest · per-event signing · PII keys | ✓ | ✓ | ✓ | ✓ |
| Retention | 30 days | 90 days | 7 years | Custom |
| Bring Your Own Storage | — | — | ✓ | ✓ |
| Evidence Packs | — | — | ✓ | ✓ |
Start recording evidence.
Every tier signs with your key from the first event.