Every x402 Payment is Now Blockchain-Verified - RelAI x Integritas

Trust is the foundation of commerce. When you pay for an API call, you should be able to prove it happened. When you receive a payment, you should have an immutable record. Starting today, every x402 payment settled through the RelAI Facilitator is automatically hashed and anchored on the Minima blockchain via Integritas.

What Changed

Every successful POST /facilitator/settle now returns a provenance field:

{
  "success": true,
  "transaction": "0xabc123...",
  "network": "skale-base",
  "provenance": {
    "provenanceHash": "e3b0c44298fc1c149afb...",
    "timestamp": "2026-02-14T00:00:00.000Z",
    "verifyUrl": "https://api.relai.fi/provenance/verify?hash=e3b0c44298fc1c149afb..."
  }
}

The provenanceHash is a SHA-256 of the settlement data (network, txHash, payer, payTo, amount, timestamp), anchored on the Minima blockchain through Integritas. This creates an immutable, independently verifiable record of every payment.

Why This Matters

Compliance

Regulated industries need proof of data acquisition. With provenance stamping, every API payment has a blockchain-backed receipt. Auditors can independently verify that a payment occurred at a specific time, for a specific amount, between specific parties.

Dispute Resolution

If there's ever a question about whether a payment was made, the provenance hash settles it. Both parties can reproduce the hash locally and verify it against the Minima blockchain - no trust in RelAI required.

AI Agent Accountability

As AI agents increasingly use x402 to pay for API access, provenance creates an audit trail. Every agent payment is recorded, verifiable, and attributable. This is critical for enterprise deployments where agent spending needs to be tracked and justified.

How It Works

User pays via x402 (EIP-3009 signature or Solana transaction)
RelAI Facilitator settles on-chain (SKALE, Base, Avalanche, Solana, etc.)
Settlement data is hashed: SHA-256(network + txHash + payer + payTo + amount + timestamp)
Hash is sent to Integritas API, which anchors it on the Minima blockchain
Provenance data is returned in the settle response

The entire process is fire-and-forget - stamping happens asynchronously and adds zero latency to payments. If Integritas is temporarily unavailable, the payment still completes normally.

Verify It Yourself

The hash is fully deterministic. You can reproduce it with any SHA-256 implementation:

import crypto from 'crypto';
const hash = crypto.createHash('sha256').update(JSON.stringify({
  network: "skale-base",
  txHash: "0xabc123...",
  payer: "0x1234...",
  payTo: "0x5678...",
  amount: "100",
  timestamp: "2026-02-14T00:00:00.000Z"
})).digest('hex');

Then verify against the blockchain:

GET https://api.relai.fi/provenance/verify?hash=

Or verify directly through Integritas at integritas.technology.

About Integritas

Integritas is a data verification middleware built on the Minima blockchain. It provides real-time hashing, timestamping, and verification of data with on-chain proof. Their API v2 supports stamping, verification, and quick checks - all backed by Minima's decentralized blockchain.

What's Next

This is Phase 1 of the RelAI x Integritas integration. Coming next:

API response provenance - hash not just the payment, but the actual API response data
Verification dashboard - visual tool to verify provenance hashes in the RelAI UI
NFT receipts - optional NFT-based proof of payment via Integritas report generation
Batch stamping - Merkle tree aggregation for high-frequency micropayments

Documentation

Full technical documentation is available at relai.fi/documentation/integritas, including API reference, hash reproduction examples, and integration details.

Every payment deserves proof. With Integritas and Minima, every x402 settlement through RelAI now has it - immutable, verifiable, and decentralized.