{"uid":"cap_5ycSOh3R0hJeVj0T3IeP9","slug":"a2a-payment-pre-payment-validator-2105c2d8","name":"A2A Payment Pre-Payment Validator","description":"a2a_payment_v1 — pre-payment validation for agent-to-agent USDC. VERIFIED or FAILED with structured violations[]. Pay Base USDC then resubmit with payment proof.","url":"https://agent-a2a-payment-mk77y.ondigitalocean.app/verify","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"context":{"type":"object"},"skill_md":{"type":"string"},"requested_permissions":{"type":"array"}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.25","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.25/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.25","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.25","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_XHK6s_rLbFCxd7FR13qhQ","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.25","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Validates agent-to-agent USDC payment requests before execution, returning VERIFIED or FAILED with structured violation details","exampleAgentPrompt":"Before I send the USDC payment, run a pre-payment validation on this agent-to-agent request — it's a POST with a JSON body containing the skill metadata and requested permissions — and tell me if it comes back VERIFIED or list all the violations I need to fix.","exampleUseCases":[{"title":"Pre-flight check before agent pays agent","prompt":"I have an agent trying to pay another agent 0.25 USDC via x402, but I want to make sure the request is valid first — can you validate the payment body with the skill metadata and permissions before I actually submit it?"},{"title":"Debugging a failed agent payment","prompt":"My agent-to-agent payment keeps getting rejected — can you run the pre-payment validator on the request body so I can see exactly which violations are causing it to fail?"},{"title":"Automated payment gating in agent pipeline","prompt":"Before each step in my agent workflow executes a USDC payment, I need you to call the a2a payment validator with the POST body and permissions list, and only proceed if it comes back VERIFIED — otherwise surface the violations to me."}],"resultDescription":"Returns a structured JSON object indicating either VERIFIED (the payment request is valid and ready to proceed) or FAILED with a violations[] array listing each specific validation error, such as missing fields, invalid permissions, or malformed body — allowing the caller to correct issues before resubmitting with payment proof.","failureModes":["Missing required 'input' object returns schema validation error","Invalid HTTP method (not POST/PUT/PATCH) causes rejection","Malformed body type (not json/form-data/text) triggers violation","Insufficient or invalid requested_permissions returns FAILED with permission violations","Network/server error on DigitalOcean host returns 5xx","Payment proof not included causes re-validation loop — must pay 0.25 USDC then resubmit"],"whenToPreferThis":"Choose this endpoint when building agent-to-agent payment pipelines that use the x402 protocol and USDC, specifically when you need structured pre-flight validation before committing a payment. It is especially useful in automated agent workflows where silent failures are costly and you need a machine-readable violations[] list to programmatically handle errors. Prefer this over ad-hoc payment submission when you want to gate execution on a VERIFIED status before spending USDC.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-15T06:36:23.576Z","isFirstParty":false}