{"uid":"cap_rKjOn71tv5GH018S5tjjm","slug":"coinopselect-proof-hash-api-e1bb79c0","name":"CoinOpSelect Proof Hash API","description":"Paid on-chain token, wallet, contract and research data over x402 on Base.","url":"https://coinop.publicvm.com/api/v1/proof/hash?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string"},"method":{"type":"string"},"queryParams":{"type":"object","required":["input"],"properties":{"input":{"type":"string","description":"Text to hash (max 8000 chars)"}}}}},"output":{"type":"object","properties":{"hash":{"type":"string"},"query":{"type":"string"}}}}},"responseSchema":{"type":"json","example":{"hash":"hex","query":"proof-hash"}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.01","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":"$0.01/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.01","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.01","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_dynmu8g538Zs1qzgPtwog","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.01","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Hashes arbitrary text input and returns a hex digest for proof or verification purposes, paid per call via x402 on Base.","exampleAgentPrompt":"Can you hash the text 'The quick brown fox jumps over the lazy dog' using the CoinOpSelect proof hash endpoint and give me back the hex digest?","exampleUseCases":[{"title":"Document fingerprinting for audit trail","prompt":"Hash this contract summary text so I have a tamper-evident fingerprint I can store on-chain: 'Parties agree to deliver 500 units by Q3 2025 at a price of $10 per unit.'"},{"title":"Proof-of-existence for a message","prompt":"I want to prove this message existed at a certain time — can you hash it for me: 'User consent recorded for account 0xABC123 on 2025-06-01'?"},{"title":"Integrity check for research data","prompt":"Take this research summary and compute its proof hash so I can verify it hasn't been tampered with later: 'Token XYZ had 1.2M daily active wallets in May 2025 with average tx value of $42.'"}],"resultDescription":"Returns a JSON object with a 'hash' field containing the hex-encoded hash digest of the input text, and a 'query' field echoing 'proof-hash' as the operation type.","failureModes":["Input text exceeds 8000 character limit — request rejected","Missing required 'input' query parameter — returns error","Payment via x402 not completed or insufficient USDC — 402 Payment Required response","Invalid method or type parameter — malformed request error","Network or server unavailability on publicvm.com — connection timeout"],"whenToPreferThis":"Choose this endpoint when you need a simple, paid, on-chain-accountable text hashing service that integrates with the x402 micropayment protocol on Base — especially useful in blockchain agent workflows where proof-of-existence or tamper-evident digests are needed without setting up your own hashing infrastructure.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-21T12:44:45.926Z","isFirstParty":false,"canonicalSlug":"coinopselect-proof-hash-api-e1bb79c0"}