{"uid":"cap_PVZdsUxTejwxhOq2H1t6b","slug":"btc-node-api-mempool-pending-transactions-f8add7a0","name":"BTC Node API — Mempool Pending Transactions","description":"Mempool pending transactions","url":"https://api.relai.fi/relay/1780781322365/api/mempool","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"],"type":"string"},"queryParams":{"type":"object","properties":{}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":null,"example":{"request":{"input":{"type":"http","method":"GET","queryParams":{}}},"response":{"success":true,"mempool_mb":"21.72","pending_tx":88165}},"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.005","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":"$0.005/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.005","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.005","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_XhXeVyB3yMUEukzfOIh86","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.005","costPer":"request","priority":0,"asset":null,"unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Returns the list of pending (unconfirmed) transactions currently in the Bitcoin mempool","exampleAgentPrompt":"Can you pull the current list of pending unconfirmed Bitcoin transactions from the mempool right now?","exampleUseCases":null,"resultDescription":"A list or collection of pending Bitcoin transactions currently sitting in the mempool awaiting confirmation, likely including transaction IDs, fees, sizes, and other metadata about unconfirmed transactions on the Bitcoin network.","failureModes":["Node connectivity issues may return 503 or empty response","Rate limiting may return 429 if called too frequently","Payment of 0.005 USDC required via x402 protocol; missing payment returns 402","Bitcoin node may be syncing, returning stale or incomplete mempool data"],"whenToPreferThis":"Use this endpoint when you need real-time access to the Bitcoin mempool — specifically the set of unconfirmed transactions — for monitoring network congestion, fee estimation context, transaction tracking, or blockchain analytics. Prefer this over block-explorer scraping when you need a direct node-level view of pending transactions.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-15T00:45:10.440Z","isFirstParty":false}