{"uid":"cap_m3Z9ACN50NR4dq5kz_1DA","slug":"fastpath-api-bitcoin-data-via-ethereum-json-rpc-0d53e79f","name":"FastPath API – Bitcoin Data via Ethereum JSON-RPC","description":"FastPath translates Ethereum-style JSON-RPC requests into Bitcoin data, fee intelligence, mempool insight, and Core v31 package signals. Paid by x402.","url":"https://api.nativebtc.org/v1/rpc","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"id":{"description":"Client-selected JSON-RPC request id."},"method":{"type":"string","description":"Ethereum-style method or FastPath method, for example eth_blockNumber, eth_getBalance, fastpath_feeLadder, or fastpath_bitcoinInsight."},"params":{"type":"array","description":"JSON-RPC params for the selected method."},"jsonrpc":{"type":"string","const":"2.0"}}},"responseSchema":{"type":"json","example":{"id":1,"result":{"cheap":{"satVb":1,"targetBlocks":144},"normal":{"satVb":1,"targetBlocks":6},"source":"core_v31_optimizer_cache","urgent":{"satVb":2,"targetBlocks":1}},"jsonrpc":"2.0"}},"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_3cWNPbYS9x3UN18XUynJE","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":"Translates Ethereum-style JSON-RPC requests into Bitcoin blockchain data, fee estimates, mempool insights, and Bitcoin Core v31 package signals.","exampleAgentPrompt":"What are the current Bitcoin fee tiers — cheap, normal, and urgent in sat/vB — using the fastpath_feeLadder method so I know how fast each target confirmation time is?","exampleUseCases":[{"title":"Optimal fee for urgent Bitcoin send","prompt":"I need to send Bitcoin right now and it has to confirm in the next block — what's the urgent sat/vB fee I should use according to FastPath's fee ladder?"},{"title":"Mempool congestion check before batching","prompt":"Before I batch a bunch of low-priority Bitcoin payouts, can you pull the current mempool state and cheap fee tier from FastPath so I can decide whether to wait or proceed?"},{"title":"Bitcoin block height via Ethereum-style RPC","prompt":"Call eth_blockNumber on FastPath and tell me the current Bitcoin block height so I can verify my node is synced."}],"resultDescription":"A JSON-RPC 2.0 response object containing fee ladder tiers (cheap, normal, urgent) each with sat/vB rate and target confirmation blocks, sourced from Bitcoin Core v31 optimizer cache, plus any additional Bitcoin data (block height, mempool state, transaction info) depending on the method called.","failureModes":["Invalid method name returns JSON-RPC error with code -32601 (method not found)","Malformed params array returns -32602 (invalid params)","Payment failure or insufficient USDC balance returns HTTP 402 before processing","Bitcoin Core backend unavailable returns -32603 (internal error)","Unsupported Ethereum method with no Bitcoin equivalent returns error response"],"whenToPreferThis":"Choose this endpoint when you need Bitcoin fee intelligence or mempool data but your agent stack is already wired for Ethereum JSON-RPC — FastPath lets you reuse existing eth_ method plumbing to get Bitcoin data without building a separate Bitcoin RPC client. Particularly useful for developers familiar with eth_blockNumber and eth_getBalance patterns who want Bitcoin Core v31 fee signals without learning a new protocol.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-15T12:33:31.642Z","isFirstParty":false}