{"uid":"cap_jG2F4iiHF7Lr34d2TMKmq","slug":"kurier-35db03ef","name":"Kurier ZK Proof API","description":"Kurier by Horizen Labs is a high-performance REST API that turns complex zero-knowledge proof workflows into a simple, pay-as-you-go service. Designed for AI agents and high-scale apps; and fully optimized for the x402 ecosystem. Submit, verify, and settle zk proofs in seconds.","url":"https://kurier.xyz/docs/x402_payments","method":"POST","headers":{},"bodySchema":null,"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"unprobed","priceSource":"unknown","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":"free","summary":"Free","primary":null,"accepted":[]},"paymentMethods":[],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Submits, verifies, and settles zero-knowledge proofs via a pay-as-you-go REST API optimized for the x402 payment ecosystem","exampleAgentPrompt":"Submit this zero-knowledge proof for verification and settlement using Kurier — here's the proof data — and pay per call via x402 so I don't need a subscription.","exampleUseCases":[{"title":"Privacy verification for confidential transactions","prompt":"I need to verify that a user completed a private transaction without revealing the actual amounts. Can you submit this zero-knowledge proof to Kurier and confirm it settles properly on the x402 network?"},{"title":"Automated compliance checks for financial apps","prompt":"We're processing hundreds of customer proofs daily to prove compliance without exposing sensitive data. Use Kurier to batch-verify these zk proofs quickly and charge us per proof so we only pay for what we use."},{"title":"Cryptographic authentication for secure logins","prompt":"I want to let users prove their identity with a zero-knowledge proof instead of passwords. Submit this authentication proof through Kurier, verify it's valid, and settle the transaction in one call."}],"resultDescription":"Returns a verification result confirming whether the submitted zero-knowledge proof is valid, along with settlement confirmation and proof status details.","failureModes":["Invalid proof data returns a rejection with proof failure details","Malformed request body returns 400 Bad Request","x402 payment header missing or invalid causes payment failure","Proof circuit mismatch causes verification error","Service timeout on large or complex proofs","Rate limiting on high-volume submissions"],"whenToPreferThis":"Choose Kurier when you need fast, scalable, pay-as-you-go zero-knowledge proof submission and verification without managing your own proving infrastructure, especially when operating in the x402 payment ecosystem or building AI-agent-driven zk workflows.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-15T00:36:45.823Z","isFirstParty":false}