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Integration Guide

This guide covers how to integrate Stableyard’s Money Account infrastructure into your application.

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Get Your API Key

Request API AccessContact us to get your API key:Full API documentation is available via Postman upon request.

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API Reference

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Account

EndpointMethodDescription
sdk/v1/registerPOSTRegister a new Money Account
sdk/v1/get-userGETGet complete user information
sdk/v1/get-user-by-addressGETGet user info by wallet address
sdk/v1/check-usernameGETCheck username availability before registration

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Vault

EndpointMethodDescription
sdk/v1/create-vaultPOSTDeploy a Safe-based vault (tracks if already created)
sdk/v1/get-balanceGETGet USD balance

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KYC

EndpointMethodDescription
sdk/v1/is-kyc-doneGETCheck if KYC is complete
sdk/v1/do-kycPOSTCreate KYC link via Sumsub

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Public

EndpointMethodDescription
/resolveGETResolve username@partner while hiding user address (privacy)

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Payments

EndpointMethodDescription
/accept-paymentPOSTCreate an order for accepting payment

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Integration Flow

1

Register Money Account

Call /register to create a Money Account linked to the user’s wallet address. Check username availability first with /check-username.
2

Deploy Vault

Call /create-vault to spin up a Safe-based vault for the user. The endpoint tracks whether a vault already exists.
3

Accept Payments

Use /accept-payment to create payment orders. This returns checkout links, QR codes, or NFC payloads depending on your use case.
4

Handle Webhooks

Listen to webhook events for payment confirmations and settlement status. See Webhooks for event types.
5

Resolve Identities

Use /resolve to look up username@partner identities without exposing vault addresses.

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Payment Channels

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Online Checkout

Accept payments via your app, website, or a hosted checkout link. 
POST /accept-payment
{
  "amount": 99.99,
  "currency": "USD",
  "settleTo": { "chain": "base", "token": "USDC" },
  "metadata": { "orderId": "order_123" }
}

Response:
{
  "paymentId": "pay_abc123",
  "checkoutUrl": "https://pay.stableyard.xyz/checkout/pay_abc123",
  "qrCode": "...",
  "status": "pending"
}

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In-Person (QR/NFC)

Turn any smartphone into a crypto POS terminal.
  1. Merchant calls /accept-payment with amount
  2. Display returned QR code or initiate NFC
  3. Customer scans/taps to pay
  4. Webhook confirms settlement

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Agentic (x402+)

AI agents can make payments via x402 protocol.
  1. Agent receives HTTP 402 “payment required” response
  2. Agent calls Money Account API to authorize payment within policy limits
  3. Payment executes automatically
  4. Agent continues with the service call

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Enterprise

Embed Money Account into your platform:
  • White-label vaults
  • Custom branding on checkout
  • Compliance-ready infrastructure with optional KYC
  • Webhook integrations for your backend systems

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Webhooks

Stableyard delivers real-time updates for:
  • payment.created — Payment order created
  • payment.pending — Awaiting user action
  • payment.completed — Payment settled
  • payment.failed — Payment failed
  • account.created — Money Account registered
  • vault.created — Vault deployed
  • kyc.completed — KYC verified
See Webhooks for verification and event payloads.

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Security

  • All API calls require authentication via API key
  • Webhook signatures should be verified
  • Vaults are non-custodial — Stableyard never holds user keys
  • Policy engine enforces on-chain transaction rules

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Support

Questions or issues?
Full Postman collection available upon API access request.