Receipt Service

The Receipt Service validates attestations and maintains the ordered transparency log.

Purpose

• Validation: 7-phase atomic validation pipeline
• Merkle tree: Ordered, verifiable attestation log
• Receipts: Cryptographic proofs of inclusion
• Persistence: Durable attestation storage

7-Phase Validation

1. Schema validation - Verify structure
2. Epoch validation - Check current epoch
3. Identity verification - Verify sidecar
4. Co-epoch attestation - Cross-verify with witness
5. Monotonic counter - Ensure ordering
6. Merkle append - Add to tree atomically
7. Persistence - Store and return proof

Submission Endpoint

const response = await fetch('https://receipts.glacis.io/api/v1/attestations', {
  method: 'POST',
  headers: {
    'Authorization': 'Bearer wt_abc123...',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    epochId: 'epoch_2024010112',
    level: 'L0',
    blindedId: 'base64...',
    requestCommitment: 'sha256...',
    signature: 'base64...'
  })
});

Receipt Response

{
  "attestationId": "att_xyz789",
  "merkleProof": {
    "root": "0x...",
    "index": 1247,
    "siblings": ["0x...", "0x..."]
  }
}

Error Codes

Code	Description
EPOCH_EXPIRED	Attestation references old epoch
IDENTITY_MISMATCH	Signature doesn’t match sidecar
COUNTER_REPLAY	Monotonic counter violation

Next Steps

• Epochs & Sampling
• Cryptographic Proofs