{"uid":"cap_NVNG8OSH7VbHzZh7jU7jU","slug":"base-mainnet-smart-contract-event-logs-3f72c016","name":"Base Mainnet Smart Contract Event Logs","description":"Smart contract event logs on Base mainnet (Base contract events) via eth_getLogs - filter by contract address and up to 4 topics, up to 2,000 blocks, raw logs with topics, data, block and tx hash.","url":"https://x402.agentindex.world/base/events?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","properties":{"topics":{"type":"array","items":{"anyOf":[{"type":"string"},{"type":"null"}]},"title":"Topics","maxItems":4},"address":{"anyOf":[{"type":"string"},{"type":"null"}],"title":"Address","default":null},"to_block":{"type":"integer","title":"To Block","minimum":0},"from_block":{"type":"integer","title":"From Block","minimum":0}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.005","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":"$0.005/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_C-XxW3fG0yzUOlZHqWMVq","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.005","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Fetches raw smart contract event logs from Base mainnet using eth_getLogs, filterable by contract address and up to 4 topics over a range of up to 2,000 blocks.","exampleAgentPrompt":"Fetch all event logs from the USDC contract at 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base mainnet between blocks 20000000 and 20001000, filtering by the Transfer topic 0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef.","exampleUseCases":[{"title":"Monitor DEX swap events on Base","prompt":"Pull all Swap event logs from the Aerodrome router contract 0xcF77a3Ba9A5CA399B7c97c74d54e5b1Beb874E43 on Base between blocks 21000000 and 21002000 — I need the raw topics and data to track liquidity activity."},{"title":"Debug a contract's recent emissions","prompt":"Can you fetch the last 500 blocks worth of events from my deployed contract at 0xAbC123... on Base mainnet so I can see what it's been emitting? Use from_block 21500000 to to_block 21500500."},{"title":"Track ERC721 mints by topic","prompt":"Get all logs from the Base NFT contract 0xd4307E0acD12CF46fD6A2C719FCC3F394DD5A44f between blocks 19800000 and 19802000 filtered by the Transfer topic 0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef and the zero-address sender topic to catch mints only."}],"resultDescription":"Returns an array of raw Ethereum event log objects, each containing: address (contract), topics array (up to 4 indexed parameters as hex strings), data (non-indexed ABI-encoded fields as hex), blockNumber, blockHash, transactionHash, transactionIndex, logIndex, and removed flag. Covers at most 2,000 blocks per call.","failureModes":["Block range exceeds 2,000 blocks — API rejects with an error","Invalid contract address format — returns error","Topic array exceeds 4 elements — rejected","No logs found in range — returns empty array","Payment not settled — 402 Payment Required response","Node RPC timeout for dense block ranges — may return partial or error"],"whenToPreferThis":"Use this endpoint when you need raw, unfiltered event logs from any smart contract on Base mainnet, especially when you want flexibility in topic filtering (up to 4 topics) or are working with non-standard events beyond ERC20 transfers. Prefer the sibling base-erc20-transfers endpoint for straightforward ERC20 Transfer event queries. Choose this endpoint when debugging contract behavior, monitoring arbitrary event emissions, or building analytics over custom Solidity events.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-11T12:46:34.524Z","isFirstParty":false,"canonicalSlug":"base-mainnet-smart-contract-event-logs-3f72c016"}