{"uid":"cap_Uh29sSRyikle7gezU8A77","slug":"signalharness-bitcoin-utxo-selection-b077accd","name":"SignalHarness Bitcoin UTXO Selection","description":"Explore 330 pay-per-call x402 API services and 27 agent-native digital products, with Base USDC pricing, secure Polar checkout, and free discovery.","url":"https://signalharness.ai/api/agent/services/bitcoin_utxo_selection/invoke","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"bitcoin_utxo_request":{"type":"string","maxLength":65536,"minLength":2}}},"responseSchema":{"type":"json","example":{"replay":false,"result":{"warnings":["This is a calculation only and does not lock, spend, or verify UTXOs."],"service_id":"bitcoin_utxo_selection","evidence_scope":"caller_supplied_data","bitcoin_utxo_selection":"{\"estimated_change_sats\":\"9860\",\"estimated_fee_sats\":\"140\",\"input_total_sats\":\"20000\",\"model\":\"p2wpkh_inputs_two_outputs\",\"selected\":[{\"txid\":\"1111111111111111111111111111111111111111111111111111111111111111\",\"value_sats\":\"20000\",\"vout\":0}],\"target_sats\":\"10000\"}"},"status":"succeeded","receipt":{"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","usage":[],"status":"succeeded","network":"eip155:8453","artifacts":[],"endedAtMs":0,"latencyMs":0,"paymentId":"example-payment","receiptId":"example-receipt","requestId":"example-request","serviceId":"bitcoin_utxo_selection","executionId":"example-execution","startedAtMs":0,"amountAtomic":"10000","resultSha256":"0758a2ac40fa9304d52f97c1d9aabe9f2d830cf6e83ba69797dbd34d8da5ef64","serviceVersion":"1.0.0","settlementReference":"0x0000000000000000000000000000000000000000000000000000000000000000"},"artifacts":[],"requestId":"example-request","executionId":"example-execution"}},"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_498o0CS05bof2ownfHK2v","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":"Selects optimal Bitcoin UTXOs for a transaction given a set of available unspent outputs and spending requirements","exampleAgentPrompt":"I need to send 0.05 BTC and I have several UTXOs available — can you run UTXO selection on my available outputs to figure out which ones to use to minimize fees and avoid unnecessary change?","exampleUseCases":[{"title":"Fee-minimizing wallet payment","prompt":"I'm building a Bitcoin transaction to pay 0.1 BTC and I have 8 UTXOs of various sizes. Run UTXO selection on them and tell me which ones to use to keep the transaction fee as low as possible."},{"title":"Avoiding dust change outputs","prompt":"I want to send exactly 0.025 BTC without creating a tiny change output. Here are my available UTXOs — which combination should I use to get a clean transaction with no dust?"},{"title":"Agent wallet automation","prompt":"My autonomous agent wallet needs to construct a Bitcoin transaction for 50,000 satoshis from a pool of UTXOs. Select the optimal UTXOs from the list I'm providing so the agent can sign and broadcast the transaction."}],"resultDescription":"Returns a JSON object containing the UTXO selection result (selected UTXOs or strategy), any warnings about the provided inputs, the service ID, evidence scope indicating the data was caller-supplied, plus a receipt with payment details, execution metadata, latency, and a SHA-256 hash of the result for verification.","failureModes":["Malformed or invalid UTXO request JSON causes a validation error","Insufficient UTXOs to cover the target amount may return warnings or an infeasible selection","Input string exceeds 65,536 character limit causing rejection","Payment failure via x402 prevents execution","Ambiguous or incomplete UTXO data may produce warnings in the result"],"whenToPreferThis":"Choose this endpoint when you need a dedicated, API-native UTXO coin selection computation without running a full Bitcoin node or wallet library locally. It is particularly useful for AI agents that need to construct Bitcoin transactions programmatically, want to minimize fees, or need an auditable, receipt-backed result for compliance. Prefer this over manual UTXO selection when handling multiple UTXOs of varying sizes where optimal subset selection is non-trivial.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-13T13:03:49.070Z","isFirstParty":false}