{"uid":"cap_IoK3YFwwEurV6Wm7Z2ClJ","slug":"blockscout-arbitrum-messages-to-rollup-cfdaabe6","name":"Blockscout Arbitrum Messages To Rollup","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/main-page/arbitrum/messages/to-rollup","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"}}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":{"type":"json","example":{"items":[{"origination_timestamp":"string","completion_transaction_hash":"string","origination_transaction_hash":"string","origination_transaction_block_number":0}]}},"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_UVZ6SH8laUCq00HEoxJiI","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 messages sent to the Arbitrum rollup layer on a specified blockchain, including origination and completion transaction details","exampleAgentPrompt":"Can you pull the list of messages sent to the Arbitrum rollup on chain ID 1 using Blockscout, so I can see the origination and completion transaction hashes?","exampleUseCases":[{"title":"Tracking L1-to-L2 bridge message status","prompt":"I need to check which messages from the main Ethereum chain have been relayed to the Arbitrum rollup — can you fetch that list from Blockscout for chain ID 1 and show me the origination and completion transaction hashes?"},{"title":"Debugging failed cross-chain message","prompt":"I think a message I sent to the Arbitrum rollup never completed — can you query Blockscout for chain 42161 and list the recent to-rollup messages so I can find the one with my origination transaction hash?"},{"title":"Monitoring rollup message throughput","prompt":"Can you pull all the messages going to the Arbitrum rollup on chain 1 from Blockscout and tell me how many have completion hashes versus pending ones, so I can monitor bridge activity?"}],"resultDescription":"Returns a JSON array of items, each containing origination_timestamp (when the message was sent), origination_transaction_hash (source chain tx hash), origination_transaction_block_number (block number on source chain), and completion_transaction_hash (rollup-side tx hash confirming delivery).","failureModes":["Invalid chain_id returns an error or empty result","Messages with no completion yet may have null completion_transaction_hash","Rate limits or payment failures return 402 Payment Required","Non-existent or unsupported chain IDs may return 404 or empty items array","Network timeouts if the Blockscout node for the chain is unavailable"],"whenToPreferThis":"Use this endpoint when you specifically need to retrieve messages flowing toward the Arbitrum rollup layer from an L1 or parent chain, including both pending and completed cross-chain messages. Prefer this over generic transaction search endpoints when you need structured bridge message data with origination and completion linkage. Choose this over block explorers' web UI when you need programmatic access to Arbitrum rollup message data at scale.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-13T18:36:45.037Z","isFirstParty":false}