X402_FACILITATOR
EIP-3009 (Direct): USDC, EURC, PR, USDG - native transferWithAuthorization, no approval needed
ERC-20 (Permit2): Any token - one-time approval to Permit2, then gasless (official x402 SDK method)
ERC-20 (Prism): Any token - one-time approval to Prism router, then gasless
Schemes: exact (per-request), upto (usage-based), batch-settlement (payment channels)
x402 v2 uses CAIP-2 network identifiers:
| Network | CAIP-2 ID |
|---|---|
| Base | eip155:8453 |
| Base Sepolia | eip155:84532 |
| SKALE Base | eip155:1187947933 |
| SKALE Base Sepolia | eip155:324705682 |
| Robinhood Chain | eip155:4663 |
| Robinhood Chain Testnet | eip155:46630 |
Base URL: https://x402.primer.systems
| Endpoint | Method | Description |
|---|---|---|
/verify |
POST | Verify payment signature without executing |
/settle |
POST | Settle payment on-chain |
/supported |
GET | List supported networks and tokens |
/health |
GET | Facilitator status |
/contracts |
GET | Prism router addresses |
/batch/deposit |
POST | Deposit to payment channel (batch scheme) |
/batch/claim |
POST | Claim from payment channel |
/batch/settle |
POST | Settle claimed funds |
/batch/refund |
POST | Refund from channel (after withdraw delay) |
/batch/channel/:id |
GET | Get channel state (requires ?network=) |
/batch/contracts |
GET | Batch settlement contract addresses |
Official x402 protocol contracts (canonical on all EVM chains):
Permit2: 0x000000000022D473030F116dDEE9F6B43aC78BA3
Exact Proxy: 0x402085c248EeA27D92E8b30b2C58ed07f9E20001
Upto Proxy: 0x4020A4f3b7b90ccA423B9fabCc0CE57C6C240002
Batch Settlement: 0x4020074e9dF2ce1deE5A9C1b5c3f541D02a10003
ERC3009 Collector: 0x4020806089470a89826cB9fB1f4059150b550004
Permit2 Collector: 0x4020425FAf3B746C082C2f942b4E5159887B0005
Primer's ERC-20 router (one-time approval, then gasless):
All Networks: 0x402357ff1e18d42d0f14a5d56d6e1ebd741b3a86