{"uid":"cap_bnRszzx7Ol2Qsr6yviapF","slug":"evm-fee-history-base-fee-priority-fee-adbb0ea8","name":"EVM Fee History — Base Fee & Priority Fee","description":"Recent base-fee and priority-fee history — Genesis402 / UnyKorn Operator Network","url":"https://twin.unykorn.org/evm-fee-history?utm_source=zero.xyz","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"params":{"type":"object","properties":{"chain":{"enum":["ethereum","base","polygon","arbitrum","optimism","bsc","avalanche","gnosis","linea","scroll"],"type":"string"},"blocks":{"type":"integer","minimum":0}}}}},"responseSchema":{"type":"json","example":{"ok":true,"type":"evm-fee-history","receipt":{"tx_hash":"0x<64hex>","amount_usd":0.004,"receipt_id":"g402-<16hex>"},"generated_at":"<iso8601>"}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.004","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":"$0.004/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.004","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.004","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_4IH1YpzIDgOj4UYPyh1FV","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.004","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Returns recent base-fee and priority-fee (tip) history for a specified EVM-compatible blockchain over a configurable number of blocks.","exampleAgentPrompt":"Can you pull the recent base fee and priority fee history for Ethereum over the last 30 blocks so I can see whether gas prices are trending up or down right now?","exampleUseCases":[{"title":"DeFi transaction timing optimizer","prompt":"Fetch the last 50 blocks of base fee and priority fee history on Arbitrum — I want to know if fees are cheap enough to submit my swap right now or if I should wait."},{"title":"Cross-chain gas cost dashboard","prompt":"Pull recent fee history for both Base and Optimism for the past 20 blocks each so I can compare which chain has lower fees for my bridge transaction."},{"title":"Gas spike alerting for smart contract deployer","prompt":"Grab the last 100 blocks of base fee history on Ethereum — I'm trying to detect if there's been a fee spike in the last few minutes before I deploy my contract."}],"resultDescription":"A JSON response containing an ok flag, a type field set to 'evm-fee-history', a receipt object with transaction hash, USD amount charged, and receipt ID, plus a generated_at ISO8601 timestamp. The core fee history data (base fees and priority fees per block) is embedded in the response for the requested chain and block count.","failureModes":["Invalid or unsupported chain name returns an error — only the ten listed chains are accepted","Requesting more blocks than available on the network may return partial data or an error","Payment failure or insufficient balance results in a 402 response without data","Network timeout or RPC node outage for the requested chain may return a 5xx error","Malformed request body (missing required params) returns a validation error"],"whenToPreferThis":"Choose this endpoint when you need structured, recent EVM fee history (both base fees and priority fees) across any of ten major chains in a single authenticated API call. It is ideal for agents that need to make gas-cost decisions, monitor fee volatility, or time transactions optimally. Prefer it over raw RPC calls when you want a unified, multi-chain interface without managing your own node connections or dealing with chain-specific RPC quirks.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-01T18:55:16.111Z","isFirstParty":false,"canonicalSlug":"evm-fee-history-base-fee-priority-fee-adbb0ea8"}