PayAI launches x402 facilitator for USDC payments

PayAI has made a production x402 facilitator available at https://facilitator.payai.network to verify signed USDC payments and settle them on public blockchains. The service validates client-signed exact x402 stablecoin payment payloads and performs on-chain settlement so resource servers do not need to hold merchant private keys. The launch and live endpoints were confirmed via PayAI documentation and the facilitator endpoints on October 1, 2026.

Developers integrate with the facilitator using the @payai/facilitator npm package and the HTTPFacilitatorClient. The production API exposes endpoints including GET /supported, POST /verify, POST /settle and GET /discovery/resources (called the Bazaar). The @payai/facilitator package defaults to the production origin; typical server setups use an x402 resource server and Express paymentMiddleware with registered schemes such as ExactEvmScheme and ExactSvmScheme.

Integrations require a receiving wallet address for each priced network and a compatible developer stack, commonly Node.js with TypeScript. The implementer must register each network and scheme, add route metadata (price, network, payTo) and prove the flow by first producing an unpaid HTTP 402 response and then running a funded buyer flow that calls POST /verify and POST /settle to produce a finalized on-chain settlement. PayAI notes that settlement_pending responses must be reconciled and that identical-body retries are idempotent.

The facilitator supports multiple networks and testnets, including Base, Polygon, Avalanche, Arbitrum, Sei, X Layer, SKALE and Solana, with live supported kinds available via GET /supported. PayAI does not custody merchant balances or provide fiat on-ramps; it performs verification and settlement only. On Solana, merchants must ensure the USDC associated token account (ATA) exists; creating an ATA requires a SOL-funded payer separate from settlement gas, and PayAI will sponsor settlement transaction gas where documented.

New receiving wallets receive an allocation of 1,000 lifetime free credits per receiving wallet and testnet settlements do not consume that allowance. Beyond the free credits, settlements are billed on a cost-plus basis: measured network gas multiplied by 1.30, charged in credits where one credit equals $0.001. A pricing snapshot from facilitator.payai.network on October 1, 2026 listed Base exact EIP-3009 at 2.31 credits (about $0.00231) per settlement and Solana mainnet exact at 1.62 credits (about $0.00162). Credits are separate from any merchant price charged to buyers; purchased credits start at $1 and are non-refundable.

Operators should note operational limits and authentication requirements. Free credits are allocated per receiving wallet but requests from shared hosts or shared IP pools can draw from a shared pool and exhaust allowances faster, returning HTTP 403 with an errorReason beginning free_tier_exhausted. After the free allowance is used, integrators must authenticate with PAYAI_API_KEY_ID and PAYAI_API_KEY_SECRET; the @payai/facilitator package reads these environment variables automatically. Documented rate limits include settle at 100 requests per second, payments-read at 200 requests per second, and discovery at 25 requests per second per IP. PayAI’s documentation and the live GET /supported and GET /pricing endpoints provide the authoritative lists of supported networks and current rates prior to production deployment.