x402
HTTP 402 payment protocol for machine-to-machine settlement, commonly used for paid API / agent tool calls.
Generally availablePayments & commerce railsAPI / SDK
Open protocol; settlement costs are chain / facilitator fees, not a SaaS list price.
核验于 2026-09-30
面向机器结算；仍需自行核对安全控制
典型任务
- Gate an API behind pay-per-request settlement
- Let an agent pay and retry after HTTP 402
限制与注意
- Requires compatible wallets / facilitators
- Not a full retail checkout UX like ACP Instant Checkout