{"uid":"cap_cmI0HQkJiHDgyGLsqfJD4","slug":"merkle-patricia-state-proof-for-evm-account-and-storage-slot-8feed360","name":"Merkle-Patricia State Proof for EVM Account and Storage Slot","description":"Merkle-Patricia state proof for an account and optional storage slot — Genesis402 / UnyKorn Operator Network","url":"https://twin.unykorn.org/evm-proof?utm_source=zero.xyz","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"params":{"type":"object","properties":{"slot":{"type":"string","pattern":"^0x[0-9a-fA-F]*$"},"block":{"type":"string"},"chain":{"enum":["ethereum","base","polygon","arbitrum","optimism","bsc","avalanche","gnosis","linea","scroll"],"type":"string"},"address":{"type":"string","pattern":"^0x[0-9a-fA-F]{40}$"}}}}},"responseSchema":{"type":"json","example":{"ok":true,"type":"evm-proof","receipt":{"tx_hash":"0x<64hex>","amount_usd":0.006,"receipt_id":"g402-<16hex>"},"generated_at":"<iso8601>"}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.006","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":"$0.006/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.006","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.006","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_ny7j3Lh08pYxF7VggypLF","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.006","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Returns a cryptographic Merkle-Patricia trie proof for an EVM account's state and an optional storage slot on supported EVM chains","exampleAgentPrompt":"Can you generate a Merkle-Patricia state proof for the Ethereum address 0xAbCd1234...5678 at the latest block, including storage slot 0x0000000000000000000000000000000000000000000000000000000000000001?","exampleUseCases":[{"title":"Cross-chain bridge state verification","prompt":"I need a Merkle state proof for address 0xDeadBeef...1234 on Arbitrum at block 'latest' — I want to verify the account balance on-chain for a bridge relay."},{"title":"Smart contract storage proof for governance","prompt":"Can you get me a Merkle-Patricia proof for storage slot 0x0000000000000000000000000000000000000000000000000000000000000002 on the Base contract at 0xAaBb...9900? I need it to prove a governance token balance for a snapshot."},{"title":"Historical account state audit","prompt":"Pull a state proof for the Ethereum address 0x1111...2222 at block number 19000000 — I need cryptographic proof of what the account's nonce and balance were at that point."}],"resultDescription":"Returns a JSON object with ok=true, a type of 'evm-proof', the Merkle-Patricia proof data for the requested account and optional storage slot, and a payment receipt containing the transaction hash, USD amount charged, and a unique receipt ID.","failureModes":["Invalid address format (not 0x-prefixed 40-char hex) returns validation error","Unsupported chain name returns enum validation error","Nonexistent or pruned block returns proof unavailable error","Invalid storage slot hex format causes parameter rejection","Payment failure or insufficient USDC balance returns 402","Node unavailability on the target chain causes timeout or 503"],"whenToPreferThis":"Choose this endpoint when you need a cryptographically verifiable Merkle-Patricia trie proof of an EVM account's state or contract storage value — for example, to feed into on-chain bridge verification, light client validation, or trustless cross-chain attestation. Prefer this over reading RPC data directly when the consumer requires proof of inclusion rather than just a value, or when you need to prove a historical state at a specific block number.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-02T04:55:43.611Z","isFirstParty":false,"canonicalSlug":"merkle-patricia-state-proof-for-evm-account-and-storage-slot-8feed360"}