x402 Integration Checklist

Review an x402 integration from HTTP challenge through payment verification and resource delivery.

x402 Integration Checklist is a 4-page PDF field guide. HTTP challenges, payment verification and resource-delivery checks.

• Challenge precisely: Terms must be parseable and bound to the actual resource request.

• Verify before work: Confirm proof, amount, asset, recipient and freshness before expensive execution.

• Make fulfillment deterministic: The same valid paid request should not produce conflicting billing outcomes.

• Observe every stage: Logs should distinguish quote, payment verification, execution and delivery acceptance.

Action checklist: Choose supported network and asset; Create signed or integrity-protected terms; Add replay and idempotency controls; Test insufficient and expired payments; Return structured receipts; Run recovery and reconciliation drills.

Use the current x402 specification; examples may change as the protocol evolves.