Facilitators: Verify and Settle

What a facilitator does

A resource server can verify and settle payments itself, but the official docs position facilitators as the practical path for most services. The facilitator understands network-specific payloads, validates scheme rules, checks whether a payment can be accepted, submits settlement where appropriate, and returns structured results to the server.

The resource server still owns access control. It decides which resources cost money, which offers are acceptable, and whether a failed or pending settlement should block the response. The facilitator provides payment execution support; it does not decide your product policy.

• Verify: check that a submitted payload matches payment requirements and scheme rules.
• Settle: submit, confirm, batch, or otherwise execute value movement according to the selected scheme.
• Report: return a response object that the resource server can encode in PAYMENT-RESPONSE.

Trust model

x402 aims to minimize trust, but a facilitator still affects liveness, correctness, and buyer safety. If it rejects valid payments, buyers cannot access resources. If it accepts invalid payloads, sellers can leak paid resources. If it handles settlement badly, accounting and refunds become hard to reconcile.

The scheme specs show why validation cannot be hand-waved. Exact payments require exact amount and destination correctness. Upto payments require maximum enforcement, time bounds, recipient binding, and replay protection. Solana flows have duplicate-settlement concerns because repeat submission behavior can differ from intuitive HTTP retry semantics.

How to evaluate one

A good facilitator evaluation looks like a payment-provider evaluation, not just an API ping. Ask which protocol versions it supports, which networks and assets it supports, whether it supports v2 headers, how it handles duplicate settlement, what its uptime target is, how it logs errors, how it reports settlement IDs, and whether it has a security review.

For mainnet payments, do not assume a testnet facilitator is appropriate. The Coinbase migration guide distinguishes the public x402.org facilitator from the CDP facilitator and shows network coverage differences. Use the current provider docs for the exact production endpoint and supported networks.

• Protocol: v2 headers, CAIP-2 networks, extension support.
• Networks: Base, Base Sepolia, Solana, Solana Devnet, and any additional chains your buyers actually use.
• Operations: latency, error model, duplicate handling, receipt fields, observability, and incident process.
• Risk: who can move funds, who can censor requests, who can see buyer metadata, and how refunds are handled.