Introduction

Ivorypay x402 lets you charge for access to APIs, files, content, or actions using the x402 HTTP payment flow. Payments are made on-chain using stablecoins across multiple EVM networks — no custodial accounts, no card networks.

Base URL

https://facilitator.ivorypay.io

All endpoint paths are prefixed with /api/x402:

https://facilitator.ivorypay.io/api/x402/initiate
https://facilitator.ivorypay.io/api/x402/build
https://facilitator.ivorypay.io/api/x402/submit
https://facilitator.ivorypay.io/api/x402/verify/:reference

What You Can Do

• Create a payment requirement for a protected resource.

• Build transaction signing data for a customer wallet.

• Ask a customer wallet to sign the payment authorization.

• Submit the signed authorization for payment processing.

• Verify a payment reference and retrieve the on-chain proof.

Two Transfer Strategies

The server automatically selects the on-chain transfer mechanism based on which chain and token the deposit uses. Your signing code must match the strategy the server chose.

Strategy	When it applies	Requires prior approval?
EIP-3009	USDC on Base, Polygon, or Lisk	No
Permit2	Any non-USDC token, or BSC / Ethereum	Yes — one-time ERC-20 approve

See Supported Assets for the full matrix.

Three Integration Flows

	Flow A — Client-Side EIP-712	Flow B — Facilitator-Assisted	Flow C — Permit2
Strategy	EIP-3009	EIP-3009	Permit2
Hash computed by	Your code	The facilitator via /build	Your code (different types)
Extra API call?	No	Yes (/build)	Yes (/build, for spender)
Best for	Full control	Most EIP-3009 integrations	BSC, USDT, non-USDC tokens

Next Steps

• Start with Quickstart to install dependencies and understand the flows.

• Review Authentication for how to pass your API key.

• Check Supported Assets for chains, tokens, and strategies.

• Follow the Payment Flow for the complete, annotated walkthrough of all three flows.

• Use the API Reference while integrating.

• See Examples for complete, copy-paste ready code.

• If your chain/token uses Permit2, complete Permit2 Approval first.