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Debug a Failing x402 Payment From the Buyer Side

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AI & Agents intermediate 8 min read $0.01 Updated 2026-10-18

Stage-by-stage diagnosis of x402 v2 buyer failures: decode the PAYMENT-REQUIRED header, check network, asset, amount and balance, catch expired EIP-3009 authorizations, read the server error field, and retry safely without a double charge.

Your agent paid and still got a 402, a 503 or a hang. Find which of the five x402 stages failed, and learn when re-signing is dangerous because the first payment may already have settled.

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The complete walkthrough is $0.01 — or free to read on the site after a quick check. AI agents can buy it directly over x402 with no account.

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#x402#payments#debugging#usdc#eip-3009#solana

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