{"uid":"cap_fxfQA-4JVoK2In7Yw_IM0","slug":"blockscout-optimism-output-roots-api-af2ba22b","name":"Blockscout Optimism Output Roots API","description":"Explore crypto activities with Blockscout's multichain search. Find transactions, addresses, tokens, and dapps across top blockchain networks — your go-to explorer for cross-chain blockchain data","url":"https://api.blockscout.com/%7Bchain_id%7D/api/v2/optimism/output-roots","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","HEAD","DELETE"],"type":"string"},"pathParams":{"type":"object","properties":{"chain_id":{"type":"string"}}},"queryParams":{"type":"object","properties":{"index":{"type":"integer"},"items_count":{"type":"integer"}}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":{"type":"json","example":{"items":[{"output_root":"string","l1_timestamp":"string","l1_block_number":0,"l2_block_number":0,"l2_output_index":0,"l1_transaction_hash":"string"}],"next_page_params":{}}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.002","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":"$0.002/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.002","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.002","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_cKHRyCoYd1nsqo7zIMK-T","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.002","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Retrieves paginated list of Optimism output roots (L2-to-L1 state commitments) for a specified blockchain chain via Blockscout","exampleAgentPrompt":"Can you pull the latest Optimism output roots for chain ID 10 from Blockscout, showing the 25 most recent entries starting from index 100?","exampleUseCases":[{"title":"Auditing L2 state root submissions","prompt":"Show me the last 50 Optimism output roots submitted to L1 for chain 10 on Blockscout — I need the L1 transaction hashes and block numbers to audit state commitments."},{"title":"Monitoring output root cadence","prompt":"Fetch the most recent Optimism output roots for chain ID 10 so I can check how frequently L2 state is being committed to L1 — give me the timestamps and L2 block numbers."},{"title":"Debugging a specific output root index","prompt":"Look up the Optimism output root at index 500 for chain 10 using Blockscout and give me the associated L1 and L2 block numbers and the root hash."}],"resultDescription":"Returns a paginated array of Optimism output root objects, each containing the output root hash, L1 timestamp, L1 block number, L2 block number, L2 output index, and the L1 transaction hash where the root was submitted. Also includes next_page_params for cursor-based pagination.","failureModes":["Invalid chain_id returns 404 or empty results","Out-of-range index returns empty items array","Malformed query params return 400 Bad Request","Rate limiting or payment failure returns 402 Payment Required","Chain not supported by Blockscout returns error or empty response"],"whenToPreferThis":"Use this endpoint when you need structured, paginated access to Optimism output root data (L2 state commitments to L1) for a specific chain via Blockscout's API. Prefer this over generic block explorers when you need machine-readable output root history with L1/L2 cross-reference data in a single call.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-11T18:54:45.884Z","isFirstParty":false}