WDK Docs

Quickstart

Integrate WDK + USDT0 settlement with P402 in a production-safe flow.

⌘KCommand-palette first navJump:QuickstartAPIErrorsMigrationSecurity

Request Builder

  • 1) Quote route (`/liquidity/quote`)
  • 2) Sign intent (WDK adapter)
  • 3) Submit signed payload (`/router/settle`)
  • 4) Read receipt and settlement metadata

Inspector

Raw exchange: 402 header -> payment signature -> facilitator response.

Tabs (mobile): Request / 402 / Payment / Response / Logs

Settlement request
curl -X POST https://p402.io/api/v1/router/settle \
  -H "Content-Type: application/json" \
  -d '{"quoteId":"q_123","routeId":"r_fast","authType":"eip3009","asset":"USDT0","amount":"1.00","payment":{...}}'

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Token rail rule (important)

  • USDT0: use eip3009 rail when chain/version supports it.
  • Legacy USDT: do not assume transferWithAuthorization; use permit/transfer fallback or bridge to USDT0 first.
  • x402 EVM reference path should be treated as EIP-3009-gated at payment-token level.

Upstream WDK source-alignment checklist (pre-GA)

  • Confirm WDK signer API names and typed-data payload format against official docs and repo examples.
  • Pin and publish validated WDK version(s) and supported chain matrix.
  • Verify terminology for AI-agent wallet flows matches official Tether wording.
  • Add explicit date/version stamp for latest upstream verification pass.