{"uid":"cap_HfCpAK9SykJDxdWq9dIw0","slug":"bitcoin-hash256-double-sha-256-3e772154","name":"Bitcoin HASH256 (Double SHA-256)","description":"Bitcoin HASH256 — SHA-256 applied twice — Genesis402 / UnyKorn Operator Network","url":"https://twin.unykorn.org/hash-double-sha256?utm_source=zero.xyz","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"params":{"type":"object","properties":{"hex":{"type":"string","pattern":"^0x[0-9a-fA-F]*$"},"text":{"type":"string","maxLength":49152}}}}},"responseSchema":{"type":"json","example":{"ok":true,"type":"hash-double-sha256","receipt":{"tx_hash":"0x<64hex>","amount_usd":0.001,"receipt_id":"g402-<16hex>"},"generated_at":"<iso8601>"}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.001","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":"$0.001/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.001","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.001","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_H5Rod8WSyMi3qE-9CJ3lN","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.001","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Computes Bitcoin's HASH256 function — SHA-256 applied twice — on a hex-encoded byte string or plain text input","exampleAgentPrompt":"Can you compute the Bitcoin HASH256 (double SHA-256) of this hex string: 0x48656c6c6f20576f726c64?","exampleUseCases":[{"title":"Verify Bitcoin transaction hash","prompt":"I have a raw Bitcoin transaction in hex — 0x0100000001... — can you run HASH256 on it so I can verify the transaction ID myself?"},{"title":"Bitcoin script opcode testing","prompt":"I'm testing OP_HASH256 behavior in a Bitcoin script. Can you double-SHA256 this hex payload 0xdeadbeefcafebabe and give me the result?"},{"title":"Hash arbitrary text Bitcoin-style","prompt":"Hash the text 'genesis block' using Bitcoin's double SHA-256 algorithm so I can see what the raw HASH256 digest looks like."}],"resultDescription":"Returns a JSON object with ok:true, the type field set to 'hash-double-sha256', the resulting digest (SHA-256 applied twice to the input), a timestamp, and a payment receipt including transaction hash, amount in USD, and a receipt ID.","failureModes":["Invalid hex string (not matching ^0x[0-9a-fA-F]* pattern) returns an error response","Text input exceeding 49152 characters is rejected","Missing both hex and text parameters results in a bad request error","Payment failure via x402 protocol prevents execution","Network timeout on the UnyKorn endpoint"],"whenToPreferThis":"Choose this endpoint when you need Bitcoin-standard double SHA-256 hashing (HASH256) as used in Bitcoin transaction ID computation, block hashing, and script opcodes. Prefer it over generic SHA-256 services when you specifically need the Bitcoin double-hash primitive, and when you want a paid, auditable receipt of the computation via the x402 micropayment protocol.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-01T06:44:39.938Z","isFirstParty":false,"canonicalSlug":"bitcoin-hash256-double-sha-256-3e772154"}