{"uid":"cap_AC_hxRyo-ZVRsjOYv44vq","slug":"basebuilder2-mempool-whale-transaction-monitor-fe94c6b8","name":"BaseBuilder2 Mempool Whale Transaction Monitor","description":"BaseBuilder Trading API hub - 20 paid endpoints","url":"https://bbx-trading.vercel.app/api/mempool/whale-tx","method":"POST","headers":{},"bodySchema":null,"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.195024","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":"$0.195024/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.195024","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.195024","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_kTi0RPdVq-Srxru6h9kl9","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.195024","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Detects and returns large whale transactions from the blockchain mempool in real time","exampleAgentPrompt":"Show me all whale transactions currently sitting in the mempool that are over 500 ETH — I want to see who's sending, who's receiving, and the transaction hashes.","exampleUseCases":[{"title":"Pre-confirmation whale sell detection","prompt":"Check the mempool right now for any pending transactions moving more than 1000 ETH and tell me the sender and receiver wallets — I want to know if any whales are about to dump."},{"title":"DeFi arbitrage opportunity spotting","prompt":"Scan the mempool for large token swaps over $500,000 in value that haven't confirmed yet — I'm looking for potential front-running or arbitrage setups."},{"title":"Whale wallet surveillance","prompt":"Is the wallet 0xABC123 currently moving any large amounts in the mempool? Alert me if there are any unconfirmed transactions from it over 100 ETH."}],"resultDescription":"Returns a list of large pending transactions from the blockchain mempool, including transaction hashes, sender and receiver addresses, token symbols, transfer values, and timestamps, filtered to surface only whale-scale activity above the configured threshold.","failureModes":["Mempool may be empty or low activity during off-peak hours, returning no results","Network congestion can cause timeouts or stale data","Invalid or unsupported chain parameter returns an error","Threshold set too high may return zero transactions","Service may have rate limits or payment failures at $0.195 per call"],"whenToPreferThis":"Choose this endpoint when you need real-time, pre-confirmation visibility into large crypto transactions — particularly for whale tracking, front-running analysis, MEV research, or market sentiment signals based on pending on-chain activity. Prefer it over block-confirmed transaction APIs when timing is critical and you need to act before a transaction settles.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-14T06:35:17.133Z","isFirstParty":false}