Facilitator Introduction

Learn about the role of an x402 facilitator

Why use an x402 facilitator

Facilitators provide shared infrastructure for verifying and settling on-chain payments for HTTP resources using the x402 protocol. They abstract multi-chain complexity, offer a consistent API for resource servers, and enable better reliability, observability, and reuse across multiple merchants and apps.

Consistent verification and settlement across schemes and networks
Offload blockchain operations and complexity from resource servers
Serve multiple merchants/apps via a stable /verify and /settle API
Help clients discover merchants via the /list endpoint

Architecture at a glance

Client: Calls protected resources and constructs payment payloads.
Resource Server: Advertises payment requirements, verifies/settles payments, fulfills requests.
Facilitator Server: Verifies payment payloads and executes settlements via standard endpoints.
Blockchain Networks: Execute and confirm payments.

Payment flow (facilitator perspective)

From the facilitator's point of view, the key steps of the protocol are:

Resource server sends a POST to the facilitator /verify endpoint with the Payment Payload and the Payment Requirements selected by the client.
Facilitator validates the payload according to the scheme and network (e.g., signatures, amounts, nonces) and returns a Verification Response.
When the server is ready to execute the payment, it sends a POST to the facilitator /settle endpoint with the Payment Payload and Payment Requirements.
Facilitator submits the transaction to the blockchain for the specified scheme/network, waits for confirmation, and returns a Payment Execution Response.

Facilitator responsibilities

Expose secure /verify and /settle endpoints that follow x402 request/response shapes
Validate Payment Payloads per scheme and network; prevent replay and ensure idempotency
Submit on-chain transactions for settlement and monitor confirmations
Provide clear error responses for verification or settlement failures
Maintain supported network coverage and RPC/wallet infrastructure
Implement observability (logs/metrics/traces), rate limiting, retries, and alerting

Getting started

CodeNut provides a hosted x402 facilitator service that makes it easy to integrate programmatic payments into your dApps. Our facilitator handles payment verification and settlement, so you don't need to maintain blockchain infrastructure.

Key features:

Zero-configuration setup - Just describe your payment requirements
Multi-chain support - Works across Ethereum, Base, Solana, and more
Automatic integration - No manual blockchain code required
Built-in security - Handles signature verification and replay protection
Real-time settlement - Fast payment processing with confirmation monitoring

Live URL: https://pay.codenut.ai/facilitator

x402 reference

For a deeper dive into the x402 protocol, payment flows, and implementation details, see the x402 Welcome Guide from Coinbase Developer Platform.

x402 Facilitator Introduction