What does a facilitator actually do during /verify and /settle?

On /verify the facilitator checks the EIP-712 signature, confirms the asset and amount match the original 402, and validates the recipient. On /settle it submits the EIP-3009 transferWithAuthorization to the chain, waits for finality, and returns a transaction hash. Some facilitators (like AsterPay) chain a second step that converts the USDC to EUR and pushes a SEPA Instant payout in the same call.

Can I run my own x402 facilitator?

Yes. The reference implementation is open source at github.com/coinbase/x402. Self-hosting a facilitator is appropriate for high-volume merchants who want full control of latency and routing. The trade-off is that you are now responsible for compliance, fraud monitoring and chain operations. Most teams use a hosted facilitator for the same reason they use Stripe instead of building a card processor.

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What is an x402 facilitator?

Q: What is an x402 facilitator?

An x402 facilitator is the trusted party that verifies an agent's HTTP 402 payment proof and executes the on-chain settlement, then forwards the result to the resource server. The default Coinbase CDP facilitator handles USDC on Base. EU-regulated facilitators like AsterPay add EUR conversion (USDC to EUR via SEPA Instant), KYA trust scoring and ERC-8004 identity attestation on top of the standard x402 flow.

Q: Why do you need a facilitator at all?

Because the resource server (the API offering paid endpoints) does not want to run blockchain infrastructure or hold the agent's private keys. The facilitator handles signature verification, on-chain settlement, fee deduction and retry logic. The merchant only needs to forward one HTTP request to the facilitator, then return the API response when the facilitator confirms success.

Q: How do facilitators differ?

They differ on six dimensions: (1) supported chains and assets; (2) settlement currency — USDC only or USDC plus EUR/GBP/USD EUR; (3) regulation — US vs EU vs unregulated; (4) trust layer — bare verification or KYA scoring; (5) latency — pure on-chain (~3 sec) vs full EUR (~10 sec); (6) pricing — most charge 25-100 bps. AsterPay is the only facilitator currently combining EUR EUR settlement with KYA trust scoring under EU regulation.

By Petteri Lehtola, Co-founder of AsterPay · Last updated 23 April 2026 · 4 min read

Answer An x402 facilitator is the trusted party that verifies an agent's HTTP 402 payment proof and executes the on-chain settlement, then forwards the result to the resource server. The default Coinbase CDP facilitator handles USDC on Base. EU-regulated facilitators like AsterPay add EUR conversion (USDC to EUR via SEPA Instant), KYA trust scoring and ERC-8004 identity attestation on top of the standard x402 flow.

Why do you need a facilitator at all?

Because the resource server — the API offering paid endpoints — does not want to run blockchain infrastructure, hold private keys, or carry compliance responsibility for moving stablecoins. The facilitator absorbs all of that. The merchant only needs to (a) return HTTP 402 with the right headers and (b) forward one HTTP request to the facilitator. When the facilitator confirms settlement, the merchant returns the API response. That is the entire integration.

What does a facilitator actually do?

The x402 specification defines two endpoints that every facilitator must expose:

POST /verify — checks the EIP-712 signature on the agent's payment payload, confirms the asset and amount match the original 402, validates the recipient and chain.
POST /settle — submits the EIP-3009 transferWithAuthorization to the chain, waits for finality, returns a transaction hash and a receipt.

Some facilitators (AsterPay being the canonical example) chain a third step transparently: convert the USDC to EUR via licensed CASP partners and push a SEPA Instant payout to the merchant's IBAN, all within the same /settle call. The merchant sees a single 200 OK with a Payment-Receipt header containing both the on-chain tx hash and the SEPA reference.

How do facilitators differ?

Dimension	Coinbase CDP	AsterPay	Self-hosted
Settlement currency	USDC only	USDC + EUR + GBP + USD	USDC (DIY EUR)
Chains	Base, Polygon	Base, ETH, Polygon, Arb, OP, Lightning	Whatever you wire
Regulation	US-regulated	EU CASP partners (MiCA), KYB via Sumsub	Your problem
Trust scoring	No	KYA v1, 0-100 score, sanctions screening	No
Latency (P95)	~3 sec (USDC only)	~10 sec (full EUR settlement)	Depends
Self-serve	Yes	Yes	Yes

Can I run my own facilitator?

Yes. The reference implementation is open source at github.com/coinbase/x402. Self-hosting is appropriate for high-volume merchants who want full control of latency, routing and fees. The trade-off: you are now responsible for compliance (MiCA in the EU; FinCEN/state MTL in the US), fraud monitoring, chain operations and 24/7 on-call. Most teams use a hosted facilitator for the same reason they use Stripe instead of building a card processor — the differentiation is in the product, not the rail.

Which facilitator should I pick?

Just need USDC on Base? → Coinbase CDP. Free at the protocol layer, well-documented, the canonical implementation.
EU merchant who needs EUR in your bank? → AsterPay. The only facilitator with native SEPA Instant settlement and MiCA-compliant CASP routing.
Need on-chain reputation and trust scoring? → AsterPay's KYA layer is the only production trust scorer for x402 right now.
Hyperscaler treasury or paranoid about counterparty risk? → Self-host the reference facilitator and own the full stack.