{"uid":"cap_d8YqHBwL5cO9TPJ1qSOjS","slug":"skills-onesource-io-f2b6b131","name":"Ethereum Pending Block (Mempool) Fetcher","description":"Fetches pending chain data for monitoring in-flight blockchain activity.","url":"https://skills.onesource.io/api/chain/pending","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET","HEAD","DELETE"],"type":"string"},"queryParams":{"type":"object","properties":{"network":{"enum":["ethereum","sepolia","robinhood"],"type":"string","default":"ethereum"}}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object","required":["data","meta"],"properties":{"data":{"type":"object","properties":{"result":{"type":["object","null"],"properties":{"number":{"type":"string"},"gasUsed":{"type":"string"},"gasLimit":{"type":"string"},"timestamp":{"type":"string"},"transactions":{"type":"array","items":{"type":"object","properties":{"to":{"type":"string"},"gas":{"type":"string"},"from":{"type":"string"},"hash":{"type":"string"},"nonce":{"type":"string"},"value":{"type":"string"}}}}}}},"description":"Endpoint-specific 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payload"},"meta":{"type":"object","required":["endpoint","request_id"],"properties":{"endpoint":{"type":"string"},"cost_usdc":{"type":"string"},"request_id":{"type":"string"},"payment_chain":{"type":"string"},"payment_token":{"type":"string"}}},"error":{"type":["object","null"],"properties":{"code":{"type":"integer"},"message":{"type":"string"}}}}}}}}},"responseSchema":null,"example":{"request":{"network":"sepolia"},"response":{"_bytes":262144,"_preview":"{\"data\":{\"result\":{\"hash\":\"0x5a4dff1eeba20ee01b02661bb163632fa2226cce48c198bdad69626457ed934b\",\"parentHash\":\"0x182ce857225703cf2fcd40ee5bfc7cc4f788453c364a456f104efd4001291381\",\"sha3Uncles\":\"0x1dcc4de8dec75d7aab85b567b6ccd41ad312451b948a7413f0a142fd40d49347\",\"miner\":\"0x14627ea0e2b27b817dbff94c3da383bb73f8c30b\",\"stateRoot\":\"0x0000000000000000000000000000000000000000000000000000000000000000\",\"transactionsRoot\":\"0x3a4aa9035c4c7ddb85e959603c886a4983d75ffb914bc5743aa815f7cedf1421\",\"receiptsRoot\":\"0xe42c73fb5f81a3fd90d7f820e3a7d76cf68a83df51c1bd22270191ac2692c03e\",\"logsBloom\":\"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\",\"difficulty\":\"0x0\",\"number\":\"0xa713ad\",\"gasLimit\":\"0x3938700\",\"gasUsed\":\"0x1c21911\",\"timestamp\":\"0x6a19f5d4\",\"extraData\":\"0xd883011103846765746888676f312e32362e33856c696e7578\",\"mixHash\":\"0xb546cff555451ee297e0264fbbeac59260e6099df90efb4035e308c119d52d7e\",\"nonce\":\"0x0000000000000000\",\"baseFeePerGas\":\"0x4654e175\",\"withdrawalsRoot\":\"0x56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421\",\"blobGasUsed\":\"0x2a0000\",\"excessBlobGas\":\"0xc692404\",\"parentBeaconBlockRoot\":\"0x6dc93a1e2692f1d0d3d5a7302ea2cc1f2b35ffb67e450510df4032a07eafd66e\",\"requestsHash\":\"0xe3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855\",\"size\":\"0x1b6b1\",\"uncles\":[],\"transactions\":[{\"type\":\"0x0\",\"chainId\":\"0xaa36a7\",\"nonce\":\"0x64e\",\"gasPrice\":\"0x121adb700\",\"gas\":\"0x249f0\",\"to\":\"0xe815718d44694ec4637cb775c468d87f6e15b538\",\"value\":\"0x0\",\"input\":\"0x095ea7b3000000000000000000000000e815718d44694ec4637cb775c468d87f","_truncated":true,"_contentType":"application/json"}},"exampleRequest":{"network":"sepolia"},"tags":["x402"],"displayCostAmount":"0.01","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"settled","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_4Adqveh2C22dgIFWlNESW","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":"Returns the pending Ethereum block containing mempool transactions not yet mined, using eth_getBlockByNumber('pending'), across multiple EVM-compatible networks","exampleAgentPrompt":"What transactions are currently sitting in the Ethereum mempool waiting to be mined — can you pull the pending block right now?","exampleUseCases":null,"resultDescription":"Returns the full pending block object including an array of unconfirmed mempool transactions (with their hashes, from/to addresses, value, gas, data, etc.) and block header fields — response can be very large (100k+ bytes) since it may contain hundreds of pending transactions.","failureModes":["Unsupported network value returns validation error","Network RPC unavailability causes timeout or 5xx error","Pending block may be empty if mempool is quiet","Response truncated for very large mempools","Payment failure returns 402 if USDC balance insufficient"],"whenToPreferThis":"Use this endpoint when you need a real-time snapshot of unconfirmed Ethereum (or EVM-compatible) transactions before they are mined — ideal for MEV research, front-running detection, gas price analysis, or monitoring specific pending transactions. Prefer this over block-by-number endpoints when you specifically need the unmined mempool state rather than confirmed blocks.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-15T06:49:16.367Z","isFirstParty":false}