Review x402 payment listings for flaws
Identify planted flaws in x402 listings, such as catalog facts or buyer client errors, to ensure payment integrity before execution.
How it works
Read-onlyFinance and payments
The agent analyzes x402 payment listings to detect flaws that models typically miss, such as incorrect catalog information or buyer client details. It checks the seller's offer, the signed header, and the receipt on Base. The agent should verify that the listing details match the actual payment state and flag any discrepancies in the HTTP 402 response or USDC authorization.
Prompt
Paste this into an agent that has the servers below connected. Adjust the names and dates to your own.
Prompt for Review x402 payment listings for flaws
Review the following x402 listing for flaws. Check for errors in the catalog, buyer client details, seller's offer, signed header, and Base receipt. Identify any planted flaws or inconsistencies that might cause payment failure.MCP servers it needs
Source
The vendor page this playbook is drawn from, and the passage that supports it.
Unaided, Sonnet named 10 of 16 planted flaws in x402 listings and Haiku 6. Most misses were facts about the catalog and the buyer client.Blog: measured notes on agent skills and x402 — AISkills402