{"uid":"cap_NAO7zJ9qdZlRSWkL6Bia8","slug":"goldkey-guard-evm-transaction-authorization-27d71dba","name":"GoldKey Guard EVM Transaction Authorization","description":"GoldKey Guard is an execution-path authorization layer for AI agents: operator-signed policy, a customer-controlled local enforcer, and signed receipts before MCP, HTTPS, or supported EVM calls run.","url":"https://goldkey-edge-storefront.noah-ing.workers.dev/v1/guard/paygo/authorize/evm","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"call":{"oneOf":[{"type":"object","required":["kind","connector_id","transaction"],"properties":{"kind":{"const":"evm_transaction"},"transaction":{"type":"object","required":["chain_id","from","value_atomic","data","nonce","gas_limit","max_fee_per_gas_atomic","max_priority_fee_per_gas_atomic"],"properties":{"to":{"type":"string","pattern":"^0x[0-9a-fA-F]{40}$"},"data":{"type":"string","pattern":"^0x(?:[0-9a-fA-F]{2})*$"},"from":{"type":"string","pattern":"^0x[0-9a-fA-F]{40}$"},"type":{"const":"eip1559"},"nonce":{"type":"string","pattern":"^(0|[1-9][0-9]{0,77})$"},"chain_id":{"type":"integer","minimum":1},"gas_limit":{"type":"string","pattern":"^(0|[1-9][0-9]{0,77})$"},"access_list":{"type":"array","maxItems":0},"value_atomic":{"type":"string","pattern":"^(0|[1-9][0-9]{0,77})$"},"max_fee_per_gas_atomic":{"type":"string","pattern":"^(0|[1-9][0-9]{0,77})$"},"max_priority_fee_per_gas_atomic":{"type":"string","pattern":"^(0|[1-9][0-9]{0,77})$"}},"additionalProperties":false},"connector_id":{"type":"string","pattern":"^[A-Za-z0-9._:-]{1,128}$"}},"additionalProperties":false}]},"schema":{"const":"goldkey.guard-request.v1"},"issued_at":{"type":"string","format":"date-time"},"signature":{"type":"string","pattern":"^[A-Za-z0-9_-]{86}$"},"idempotency_key":{"type":"string","pattern":"^[A-Za-z0-9._:-]{8,128}$"},"installation_id":{"type":"string","pattern":"^gki_[A-Za-z0-9_-]{43}$"}}},"responseSchema":{"type":"json","example":{"schema":"goldkey.guard-authorization-envelope.v1","receipt":{"decision":"ALLOW","reason_codes":[]},"evidence":{"schema":"goldkey.guard-evidence.v1","decision":"ALLOW","reason_codes":[]},"signature":"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA","receipt_sha256":"0000000000000000000000000000000000000000000000000000000000000000"}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.1","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":"$0.1/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.1","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.1","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_NiJcIqqX8MiGSbABoBjc7","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.1","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Authorizes or blocks an EVM blockchain transaction against operator-signed policy and returns a cryptographically signed receipt required before execution proceeds.","exampleAgentPrompt":"Before submitting this EIP-1559 transaction — from 0xAbC...123 to 0xDeF...456 on chain 1, with 0 ETH value and this calldata — run it through GoldKey Guard with my installation ID gki_... and idempotency key tx-001, and only proceed if you get back an ALLOW receipt with a valid signature.","exampleUseCases":[{"title":"DeFi agent pre-execution gating","prompt":"I have an AI agent about to call a Uniswap contract on Ethereum mainnet (chain 1). Before it broadcasts the transaction, check it against my GoldKey policy using installation ID gki_... and idempotency key swap-20240601-001 — only let it go through if the decision comes back ALLOW."},{"title":"Operator policy enforcement for token transfers","prompt":"My agent wants to send a ERC-20 transfer transaction (0x calldata, from 0xSender, to 0xToken contract, chain 8453, zero ETH value) — authorize it against our company's GoldKey Guard policy and return the signed receipt so we have an audit record."},{"title":"Block unauthorized smart contract calls","prompt":"Before my agent executes any smart contract interaction on chain 137, I want GoldKey Guard to check it against our operator-signed rules and either ALLOW or BLOCK it — please run this pending EVM transaction through authorization with idempotency key agent-op-xyz and give me the decision and receipt."}],"resultDescription":"A JSON envelope (goldkey.guard-authorization-envelope.v1) containing: a decision field (ALLOW, REVIEW, or BLOCK) with reason codes, an evidence object with the same decision and codes, a base64url signature over the receipt, and a SHA-256 hash of the receipt — all required as proof of authorization before the EVM transaction may be submitted.","failureModes":["Invalid or missing signature on the request body returns 401/403","Malformed EVM address (not matching ^0x[0-9a-fA-F]{40}$) causes schema validation failure","Unknown installation_id returns policy-not-found error","Duplicate idempotency_key with different payload may return conflict error","Policy decision of BLOCK or REVIEW means the transaction must not proceed","Payment of 0.1 USDC not included or invalid causes 402 Payment Required","Expired issued_at timestamp may cause request rejection","Network/worker failure returns 5xx and no receipt is issued"],"whenToPreferThis":"Use this endpoint when you need a cryptographically signed authorization receipt specifically for EVM blockchain transactions before they execute — especially in AI agent pipelines where auditability, operator-policy enforcement, and non-repudiation of on-chain actions are required. Prefer this over generic policy checks when the call type is an EIP-1559 EVM transaction with chain ID, gas parameters, and calldata, and you need the signed receipt as a gate before broadcasting. Use the sibling MCP/HTTPS endpoint instead for non-EVM tool calls.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-15T18:32:22.156Z","isFirstParty":false}