{"uid":"cap_YLJcO2SrkPIybvUDpC9vX","slug":"base-gas-oracle-eip-1559-fee-tiers-ed72321a","name":"Base Gas Oracle – EIP-1559 Fee Tiers","description":"Pay-per-call crypto microdata for trading/onchain AI agents via x402 (USDC on Base): Base gas, token risk, balances, multi-venue prices, Hyperliquid book/funding, kimchi premium. No API keys.","url":"https://kr-x402-mvp.kgy5612.workers.dev/crypto/gas?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"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET"],"type":"string"},"queryParams":{"type":"object","properties":{"gas_limit":{"type":"integer","maximum":30000000,"minimum":21000,"examples":[21000,150000],"description":"Gas units to price (default 21000)"}},"additionalProperties":false}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":{"type":"json","example":{"block":37000000,"chain":"base","tiers":{"fast":{"est_cost_usd":0.0007,"max_fee_gwei":0.025,"max_priority_fee_gwei":0.01},"slow":{"est_cost_usd":0.0005,"max_fee_gwei":0.006,"max_priority_fee_gwei":0.001},"standard":{"est_cost_usd":0.0005,"max_fee_gwei":0.011,"max_priority_fee_gwei":0.001}},"sources":["https://mainnet.base.org"],"chain_id":8453,"tx_fields":{"gas":"0x5208","type":"0x2","maxFeePerGas":"0xa7d8c0","maxPriorityFeePerGas":"0xf4240"},"congestion":0.42,"updated_at":"2026-10-29T13:30:00Z","base_fee_gwei":0.005,"gas_price_gwei":0.006,"recommended_tier":"standard","gas_price_wei_hex":"0x5b8d80","est_transfer_cost_eth":1.26e-7,"max_priority_fee_gwei":0.001,"max_priority_fee_wei_hex":"0xf4240"}},"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_rUUyaahMOsFHMA3i6H5Q1","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 current Base network gas prices in slow/standard/fast EIP-1559 tiers with estimated USD costs, congestion level, and ready-to-use tx fields for a given gas limit.","exampleAgentPrompt":"What are the current EIP-1559 gas prices on Base right now — give me the slow, standard, and fast tiers with estimated USD costs for a standard ETH transfer (21000 gas)?","exampleUseCases":[{"title":"Pre-flight gas check before sending payment","prompt":"Before I send this USDC transfer on Base, check the current gas fees and tell me the recommended tier with its estimated USD cost so I know how much the tx will actually cost me."},{"title":"Congestion monitoring for trade timing","prompt":"Is the Base network congested right now? Give me the current gas tiers so I can decide whether to wait for lower fees before submitting my trade."},{"title":"Gas estimation for a complex contract call","prompt":"I'm about to call a DeFi contract on Base that uses about 150000 gas units — what will that cost me in USD at the standard and fast tiers right now?"}],"resultDescription":"A JSON object with the current Base block number, base fee in gwei, slow/standard/fast EIP-1559 tiers (each with maxFeePerGas, maxPriorityFeePerGas, and estimated USD cost), a congestion score 0–1, the recommended tier, and ready-to-use hex-encoded tx fields (type 0x2, gas, maxFeePerGas, maxPriorityFeePerGas).","failureModes":["RPC unavailability from mainnet.base.org causes 502/503 with no gas data","Payment failure (402) if x402 USDC payment on Base is not included or insufficient","Invalid gas_limit outside 21000–30000000 range returns 400 validation error","Stale data if Base RPC is lagging; updated_at timestamp indicates freshness"],"whenToPreferThis":"Use this endpoint when an AI agent needs real-time EIP-1559 gas parameters specifically for Base mainnet before constructing or pricing a transaction. Prefer it over generic Ethereum gas APIs when the target chain is Base (chain_id 8453). The pay-per-call x402 model (no API key required) makes it ideal for autonomous agents that cannot manage long-lived credentials.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-31T18:42:25.853Z","isFirstParty":false,"canonicalSlug":"base-gas-oracle-eip-1559-fee-tiers-ed72321a"}