{"uid":"cap_w05WMZElR1FOVECgoHnaM","slug":"evm-pending-block-status-d6cca166","name":"EVM Pending Block Status","description":"The chain's pending block: how many transactions are queued for the next block, the base fee they will pay, and the gas already used against the limit. This is the node's own view of what is about to be mined, so it answers \"is the chain congested right now\" without an indexer. Transaction hashes are included when the node returns them. EVM chains: ethereum, base, polygon, arbitrum, optimism.","url":"https://agent402.tools/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"],"type":"string"},"queryParams":{"type":"object","required":[],"properties":{"hashes":{"type":"boolean","description":"Include the pending transaction hashes (default false, counts only)"},"network":{"type":"string","description":"ethereum | base | polygon | arbitrum | optimism (default base)"}}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object","required":["network","number","transactionCount","baseFeePerGas","baseFeePerGasGwei","gasUsed","gasLimit","timestamp","note"],"properties":{"note":{"type":"string"},"number":{"type":"string"},"gasUsed":{"type":"string"},"network":{"type":"string"},"gasLimit":{"type":"string"},"timestamp":{"type":"string"},"baseFeePerGas":{"type":"string"},"transactionCount":{"type":"integer"},"baseFeePerGasGwei":{"type":"string"}}}}}}},"responseSchema":{"type":"json","example":{"note":"A pending block is the node's own view and differs between nodes; it is not a consensus value.","number":"34881204","gasUsed":"12904331","network":"base","gasLimit":"150000000","timestamp":"2026-09-12T21:30:11.000Z","baseFeePerGas":"4218231","transactionCount":61,"baseFeePerGasGwei":"0.004218"}},"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_A0n-lu2Y1UGnAf-Gfxk9R","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":"Returns the pending block details for an EVM chain, including queued transaction count, base fee, and gas usage, giving a real-time view of mempool congestion without an indexer.","exampleAgentPrompt":"What does the current pending block look like on Ethereum — how many transactions are queued, what's the base fee in gwei, and how close are we to the gas limit?","exampleUseCases":[{"title":"Gas fee check before transaction","prompt":"Before I submit my ETH transfer, can you check the current base fee on Ethereum and tell me if it's congested right now?"},{"title":"Arbitrum congestion monitoring","prompt":"Is Arbitrum busy at the moment? I need to know the pending transaction count and current base fee in gwei before I deploy my contract."},{"title":"Comparing network conditions across chains","prompt":"Can you pull the pending block info for both Base and Polygon so I can see which one has a lower base fee and fewer queued transactions right now?"}],"resultDescription":"Returns a JSON object with the network name, pending block number, number of queued transactions, base fee in wei and gwei, gas used, gas limit, and block timestamp. Optionally includes an array of pending transaction hashes. Includes a note that the pending block is the node's own view and not a consensus value.","failureModes":["Unsupported network name returns an error — only ethereum, base, polygon, arbitrum, optimism are valid","Node-level variance: pending block contents differ between nodes so results may not match other sources","No indexer backing means very recent transactions may not appear","Missing or malformed query parameters may result in default values being applied silently","Payment failure (402) if USDC balance is insufficient"],"whenToPreferThis":"Use this endpoint when you need a real-time, lightweight snapshot of EVM chain congestion — specifically pending transaction queue depth, base fee, and gas utilization — without spinning up your own node or relying on a third-party indexer. Ideal for agents that need to decide whether to submit a transaction now or wait, or to compare gas conditions across supported EVM chains.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-14T06:44:42.079Z","isFirstParty":false}