{"uid":"cap_xmeVuEEMdBeZDWWkknO0G","slug":"base-pending-block-d4fbb5d1","name":"base-pending-block","description":"The current pending Base mainnet block (mempool, not yet mined) - unconfirmed transactions via eth_getBlockByNumber('pending').","url":"https://x402.agentindex.world/base/pending?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method","bodyType","body"],"properties":{"body":{"type":"object","title":"PendingInput","properties":{}},"type":{"type":"string","const":"http"},"method":{"enum":["POST","PUT","PATCH"],"type":"string"},"bodyType":{"enum":["json","form-data","text"],"type":"string"}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object","title":"BlockOutput","required":["number","hash","parent_hash","timestamp","miner","gas_used","gas_limit","transaction_count","transaction_hashes"],"properties":{"hash":{"type":"string","title":"Hash"},"miner":{"type":"string","title":"Miner"},"number":{"type":"integer","title":"Number"},"gas_used":{"type":"integer","title":"Gas Used"},"gas_limit":{"type":"integer","title":"Gas Limit"},"timestamp":{"type":"integer","title":"Timestamp"},"parent_hash":{"type":"string","title":"Parent Hash"},"base_fee_per_gas":{"anyOf":[{"type":"integer"},{"type":"null"}],"title":"Base Fee Per Gas","default":null},"transaction_count":{"type":"integer","title":"Transaction Count"},"transaction_hashes":{"type":"array","items":{"type":"string"},"title":"Transaction Hashes"}}}}}}},"responseSchema":null,"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_o-nscjMNHfxn43UbR2ZH0","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":"Fetches the current pending block on Base mainnet, including unconfirmed mempool transactions, via eth_getBlockByNumber('pending').","exampleAgentPrompt":"What transactions are currently sitting in the Base mainnet mempool — can you pull the pending block and tell me how many unconfirmed transactions there are, the current base fee per gas, and the gas limit?","exampleUseCases":[{"title":"Mempool congestion monitoring","prompt":"Check the Base mainnet pending block right now and tell me how congested the mempool is — how many unconfirmed transactions are queued and what's the current base fee per gas?"},{"title":"Pre-submission gas fee estimation","prompt":"Before I submit my Base transaction, pull the current pending block so I can see the base fee per gas and decide whether to wait for lower fees."},{"title":"Real-time DeFi arbitrage scouting","prompt":"Fetch the Base pending block immediately and give me the full list of unconfirmed transaction hashes so I can scan for arbitrage opportunities in the mempool."}],"resultDescription":"Returns a structured object representing the current pending Base mainnet block, including block number, block hash, parent hash, Unix timestamp, miner address, gas used, gas limit, base fee per gas, the count of pending transactions, and an array of all pending transaction hashes.","failureModes":["Node provider unavailable or rate-limited — returns error with no block data","Pending block temporarily empty or unavailable — may return zero transactions","Payment not received — x402 payment required before data is returned","Network instability causing stale or inconsistent pending block snapshot"],"whenToPreferThis":"Use this endpoint when you need a real-time snapshot of unconfirmed transactions on Base mainnet — ideal for mempool analysis, gas fee estimation before submitting a transaction, MEV/arbitrage scouting, or monitoring network congestion. Prefer this over confirmed-block endpoints when you specifically need pre-mining transaction data.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-20T12:38:41.720Z","isFirstParty":false,"canonicalSlug":"base-pending-block-d4fbb5d1"}