Receipts & verification

Every response is signed — Ed25519 or post-quantum ML-DSA-65. Verify attestations independently.

What a receipt attests

A receipt is a signed statement binding the delivered bytes' metadata: which sources contributed, which pool and extractor produced the output, the real-time quality score and health-test outcomes at generation time, and a nanosecond timestamp. The signature is computed over the canonicalized receipt (sorted keys, signature field removed, compact JSON), so any tampering invalidates it.

Receipt fields

Field	Meaning
request_id	Unique id, also usable to re-fetch the receipt later.
policy / pool_id	Requested policy and the tier pool that served it.
contributing_sources	Every source that fed the output.
quality_score	Real-time score from the streaming quality stage.
rct_pass / apt_pass	Repetition-count and adaptive-proportion health tests.
extractor_alg / drbg_alg	Conditioning extractor and output DRBG.
input_min_entropy_bits	Assessed min-entropy of the raw input.
output_bytes	Number of bytes delivered.
timestamp_unix_ns	Generation time (Unix nanoseconds).
raw_entropy_stored	Always false — raw entropy is never retained.
signature_alg / signature	Ed25519 or ML-DSA-65 signature over the canonical form.

Signature keys

GET /v1/pubkey returns the active algorithm and public key. Production deployments sign with ML-DSA-65 (FIPS 204 post-quantum); Ed25519 is used in development. SDKs pin this key once (fetch_verifier() in Python, verifierPublicKey in JavaScript) and then verify every response.

Verifying

Python

cli = EntropyClient("http://localhost:8080")
cli.fetch_verifier()                     # pin key; every call now auto-verifies

r = cli.get_bytes(32, policy=Policy.HIGHEST_QUALITY)
# r.bytes_ is only returned after the signature check passes.

JavaScript

import { verifyReceipt, canonicalReceiptBytes } from '@lightrider/entropy';

const ok = await verifyReceipt(receipt, pinnedPublicKey);
if (!ok) throw new Error('receipt signature invalid');

Note

The dashboard's Receipts page performs the same verification in-browser: paste or select a receipt and it checks the signature against the pinned key.

Re-fetching & audit

Receipts are retrievable after the fact by request id via GET /v1/receipts/:request_id, so an auditor can confirm that a stored receipt matches what the platform issued. Each receipt also carries an audit_event_id linking it to the append-only audit trail.