---
title: Legal-document snapshots
description: Publish legal-document versions and sign evidence of the exact
  document shown by your application.
group: self-host
lastModified: "2026-10-10T16:01:45+01:00"
---
## Publish the current release

The backend can store the current version and content hash of a legal document.
Synchronize the release from trusted server or deployment code with a configured
API key:

```bash
curl -X PUT 'http://localhost:3000/api/c15t/legal-documents/terms_and_conditions/current' \
  -H "Authorization: Bearer $C15T_API_KEY" \
  -H 'Content-Type: application/json' \
  -d '{"version":"3.0","hash":"YOUR_DOCUMENT_CONTENT_HASH","effectiveDate":"2026-09-10T00:00:00.000Z"}'
```

From a Node.js deploy script, the [Node.js SDK](/docs/self-host/api/node-sdk#publish-a-legal-document-from-ci)
sends the same request with a client created with `apiKey`:

```ts
const result = await c15t.legalDocuments.publish('terms_and_conditions', {
	version: '3.0',
	hash: 'YOUR_DOCUMENT_CONTENT_HASH',
	effectiveDate: '2026-09-10T00:00:00.000Z',
});

if (!result.ok) {
	throw result.error;
}
```

The SDK retries network errors, timeouts and the statuses listed in
[retries and timeouts](/docs/self-host/api/node-sdk#retries-and-timeouts).
Republishing the same release is safe.

Compute the hash from the exact published document using your application's
chosen content-hashing convention. Keep the same type, version, hash and
effective date when rendering and recording acceptance. A conflicting release
identity returns an error instead of silently changing the existing record.

## Sign a document snapshot

The package exports signing and verification helpers. Call them explicitly from
your server application. Merely setting `legalDocumentSnapshot` on the backend
does not add an HTTP endpoint that issues or consumes these tokens.

```ts title="src/legal-document-snapshot.ts"
import {
	createLegalDocumentSnapshotToken,
	verifyLegalDocumentSnapshotToken,
} from '@c15t/backend';

const signingKey = process.env.LEGAL_DOCUMENT_SIGNING_KEY;
if (!signingKey) throw new Error('Set LEGAL_DOCUMENT_SIGNING_KEY');
const options = { signingKey, ttlSeconds: 86400 };

export async function signTermsSnapshot() {
	return createLegalDocumentSnapshotToken(
		{
			type: 'terms_and_conditions',
			version: '3.0',
			hash: 'YOUR_DOCUMENT_CONTENT_HASH',
			effectiveDate: '2026-09-10T00:00:00.000Z',
			tenantId: 'your-tenant',
		},
		options
	);
}

export async function verifyTermsSnapshot(token: string) {
	return verifyLegalDocumentSnapshotToken(token, options, 'your-tenant');
}
```

Supply release metadata from your trusted document store, rather than accepting
it unverified from a browser. Return the signed token alongside the displayed
document. When the user submits acceptance, verify it on the server, check the
expected document identity and record the accepted document through your
application's consent flow. A valid signature does not establish a user action
or authorize an identity by itself.

## Handle verification failures

Without a signing key, creation returns `undefined`. Verification returns either
`{ valid: true, payload }` or `{ valid: false, reason }`. A missing token or key
uses `reason: 'missing'`; signature, expiry and audience failures use `invalid`.
Do not record verified-document evidence after either failure.

The default issuer is `c15t`. The default audience is scoped by `tenantId`, and
the default lifetime is one day. Use the same trusted tenant during signing and
verification. These helpers use HS256 and need a server-only signing secret.

Legal-document snapshots describe a version and hash. `/init` policy snapshot
tokens describe the policy decision for a visitor. They use separate settings,
audiences and lifetimes; do not interchange the tokens.