# Rubric Attested Verification Event Custody

> Rubric Attested Verification Event Custody is a paid API for AI agents from rubric-protocol.com, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-14).

Seals and anchors a privacy-preserving attestation of an identity/liveness/KYC verification event — including method, provider, and outcome — using post-quantum ML-DSA-65 signatures and Hedera HCS, without exposing the subject's identity.

## Facts

- Endpoint: POST https://rubric-protocol.com/v1/x402/attested-verification
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/rubric-attested-verification-event-custody-d4377644
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_hlmBDOJ3dA3jMim3VkjXG

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability rubric-attested-verification-event-custody-d4377644 -d '<json body>'
```

Example prompt: Seal an attestation that a KYC check just ran for subject hash 'sha256:a3f9...', using the 'document_scan' method via provider 'Onfido', with a result of 'pass' — anchor it to Hedera and sign it post-quantum so I can prove it happened forever without revealing who the subject is.

## When to prefer this

Choose this endpoint when you need a privacy-preserving, legally auditable, tamper-proof record that a verification event occurred — without any PII touching the attestation service. It is superior to generic logging when you need post-quantum cryptographic proof, Hedera blockchain anchoring for immutability, or a portable credential you can share with third parties to prove a check ran without re-running it. Prefer it over raw KYC provider APIs when the requirement is proof-of-check rather than performing the check itself.

## Known failure modes

- Missing required fields (type or method) returns a 400 validation error
- Invalid or malformed subjectRef format causes rejection
- Hedera HCS anchoring failure results in a 503 or retry-required response
- x402 payment of $0.005 USDC not fulfilled causes 402 Payment Required before processing
- Duplicate submission of same subjectRef+event may create a new independent record (non-idempotent)
- Network timeout during post-quantum signing step may return a 504

## How this service works

Attested verification-event custody: seal the fact that an identity/liveness/KYC check ran, its method, provider, and re

## Output

A sealed, ML-DSA-65 post-quantum-signed attestation record containing the verification event metadata (type, method, provider, outcome, timestamp), an opaque subjectRef binding the record to the subject without exposing identity, and a Hedera HCS topic anchor providing permanent, publicly verifiable proof that the attestation exists and has not been tampered with.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "type": "object"
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json"
     ],
     "type": "string"
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "format": {
     "type": "string"
    },
    "example": {}
   },
   "additionalProperties": false
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/rubric-attested-verification-event-custody-d4377644/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from rubric-protocol.com](https://www.zero.xyz/host/rubric-protocol.com/llms.txt)