x402 v2 · BASE USDC · PAYMENT READINESS

Before your agent pays,
read the quote.

Paste a PAYMENT-REQUIRED header. Instantly see the network, token contract, micro-USDC price and recipient. Understand what was requested before you approve any wallet action.

결제 전에 체인·USDC 자산·요청 금액·수령 주소를 무료로 확인하세요. 입력값은 서버에 전송하지 않습니다.

A real x402 invoice lookup problem can return a 1,000 USDC placeholder for a 0.10 USDC invoice. Enter the expected invoice amount below; this page flags an exact mismatch and any merchant-reported issuance denial. No payment is initiated. Original independent user report ↗. This public report is not an endorsement of this tool or evidence of our paid customers.

Merchant debugging: public x402 headers can be too large for some HTTP clients and proxies to accept. This tool now measures an observed Base64 PAYMENT-REQUIRED field or estimates one from JSON, with conservative 2/8/16 KiB transport warnings and a ranked hypothetical byte-saving breakdown for optional Bazaar metadata (values are not displayed). It does not establish compatibility with any particular stack, and it never makes a payment. Independent upstream field-size report ↗.

For failed/rejected payment attempts, a public PAYMENT-REQUIRED quote may also contain an untrusted server error field. We show it locally without treating it as a verified facilitator diagnosis or permission to retry. Never paste a signed payment header.

0Uploads / 업로드

0Wallet signatures

6USDC decimal places

LOCAL WORKBENCH / 무료 도구

Inspect a public quote

NO CONNECT

PAYMENT-REQUIRED header or decoded JSONOnly a public unsigned merchant quote. Never paste PAYMENT-SIGNATURE, wallet seed, bearer token, customer data or private credentials.

Display budget (native Base USDC)Warning threshold; not a wallet limit.Default 0.020000 · No payment is authorized

Expected invoice amount (optional, native Base USDC)Enter the real invoice's intended USDC price (e.g. 0.10). Purely a local price mismatch check, never a wallet spending cap or signature authorization. Do not paste an invoice ID, wallet seed or signed payment.If the HTTP 402 asks for 1000 but your invoice is 0.10, the tool displays STOP. Merchant-declared invoice_not_found also triggers STOP, even if the price matches. No wallet is connected.

⦿ Your input is processed only by JavaScript in this browser. This page makes no network requests to inspect a quote, has no analytics and stores no input. It never fetches an arbitrary API or connects a wallet.

REAL MERCHANT FEEDBACK · OPTIONAL / 무료 사용자 의견

What is blocking your x402 checkout?

Tell us which real problem matters and whether you would consider a separate paid diagnosis. This is not a sale, order, wallet connection, payment, analytics beacon, or claim that anyone has bought our service. We need actual user feedback to decide what to improve. Please do not paste any payment headers, payloads, addresses, secret keys or customer data.

Client type / 환경 Observed blocker / 문제 Would you consider paying for verified help? / 비용 지불 의향 Reply address (optional) / 회신 이메일

What would prove value? (optional, public general information only)

Separate 9-USDC fixed report listing ↗

This form sends only its named controls after you click Send and consent. It does not read, serialize, upload, or attach the unsigned quote you pasted in the free inspector. Email is optional; without it no reply is possible. The provider may require an anti-spam check. Answers are not independently verified paid demand, contracts or customer receipts.

FROM A FREE CHECK TO A PAID SERVICE · OPTIONAL

Need a machine-readable report?

This browser preview is free forever. For a structured hosted x402 v2 quote consistency report, a separate existing VM5 service can process a buyer-supplied public unsigned quote and return a JSON analysis after the buyer independently authorizes a payment.

Optional original hosted API0.010000 native Base USDC / authorized GETchain eip155:8453 · Circle native USDC · x402 v2

View free fictional hosted JSON example ↗Current API parameters and price ↗Request custom integration QA ↗Order one tailored x402 header overflow report · 9 Base USDC ↗Merchant browser CORS compatibility QA · scoped 49 USDC ↗

Want to see a real buyer-controlled x402 flow? Try the free-first CSV checker and optional 0.005 Base USDC browser-wallet checkout ↗. It is a different service, with its own explicit CSV-upload consent and separate wallet signature. An unsigned quote is free; actual payment is optional. This beta still has zero independently verified paid buyer-owned CSV POST orders.

Separate real seller listing: An opt-in 9-native-Circle-Base-USDC Clawlancer fixed-price report for ONE permitted public unsigned header is live. Its checkout happens on Clawlancer, not this free tool. A listing is not an order; zero purchases are verified. Never share a private invoice or signed header with a seller.

No instant checkout on this page. The paid GET /v1/x402-preflight endpoint uses HTTP 402; a quote is not a payment. No paid customer of this particular endpoint is independently confirmed. Only use it with your own wallet and trusted x402 client, after checking live terms. No refunds, settlement or purchaser identity are inferred from a preview.

What a quote inspection can—and cannot—tell you

Can inspect

Base CAIP-2 network, literal native Circle USDC contract, exact positive six-decimal USDC amount, HTTP resource field, 20-byte payTo format, and a voluntary budget threshold.

Cannot guarantee

Authenticity, merchant identity, who controls the payTo key, on-chain balances, invoice matching, whether payment settles, client wallet support, or contract safety. No remote verification is performed.

Nothing is signed

No seed phrases, API keys, payment signatures, wallet connections, token approvals, gas payments, or x402 facilitator are used by the free checker.

Before your agent pays,read the quote.