{"uid":"cap_ued6LK8Dne-soKt9tblAm","slug":"base-eip-1967-proxy-resolver-4ba6dfe2","name":"Base EIP-1967 Proxy Resolver","description":"EIP-1967 proxy resolver for a Base contract: implementation, admin, beacon addresses + is_proxy. Use when an agent must know what code actually runs behind a proxy before trusting or calling it.","url":"https://x402-data-api.sigrunner.workers.dev/chain/proxy-info?utm_source=zero.xyz","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"],"type":"string"},"queryParams":{"type":"object","properties":{"address":{"type":"string","description":"0x-prefixed contract address on Base"}}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object","required":["address","is_proxy","implementation","admin","beacon","chain"],"properties":{"admin":{"type":"null"},"chain":{"type":"string"},"beacon":{"type":"null"},"address":{"type":"string"},"is_proxy":{"type":"boolean"},"implementation":{"type":"null"}}}}}}},"responseSchema":{"type":"json","example":{"admin":null,"chain":"base","beacon":null,"address":"0x4200000000000000000000000000000000000006","is_proxy":false,"implementation":null}},"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_uIwHjSPo5xzDZlaS0may0","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":"Resolves EIP-1967 proxy metadata (implementation, admin, beacon addresses and is_proxy flag) for any contract on Base mainnet","exampleAgentPrompt":"Before I interact with the contract at 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base, check if it's an EIP-1967 proxy and tell me the actual implementation address running behind it.","exampleUseCases":[{"title":"Verify DeFi protocol contract before trading","prompt":"I'm about to call a lending protocol on Base at 0x3d9819210A31b4961b30EF54bE2aeD79B9c9Cd3b — is it a proxy and what's the real implementation contract behind it?"},{"title":"Detect upgradeability risk in a token contract","prompt":"Check if the ERC-20 at 0x4200000000000000000000000000000000000006 on Base is an upgradeable proxy — I need to know if there's an admin who can swap out the logic."},{"title":"Audit proxy chain before smart contract integration","prompt":"We're integrating with a Base contract at 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48 — resolve its EIP-1967 proxy slots so I can see the implementation, admin, and beacon addresses before we go live."}],"resultDescription":"A JSON object containing the queried contract address, a boolean is_proxy flag, and nullable implementation, admin, and beacon addresses, plus the chain identifier ('base'). If the contract is not a proxy, implementation/admin/beacon will be null and is_proxy will be false.","failureModes":["Invalid or missing address parameter returns an error or unexpected result","Non-Base chain addresses will not return valid proxy data (endpoint is Base-specific)","Contract address that doesn't exist on Base may return is_proxy: false with all nulls","Malformed 0x address (wrong length, non-hex) may cause a parsing error","Network timeout or Cloudflare Worker outage returns a 5xx error","Payment failure via x402 protocol returns 402 with payment requirements"],"whenToPreferThis":"Choose this endpoint when an agent needs to introspect a specific Base contract's proxy architecture before trusting or calling it — especially in DeFi security checks, pre-trade validation, or contract auditing workflows. It is purpose-built for EIP-1967 proxy resolution on Base, making it more precise than general contract ABI tools or block explorers. Prefer it over the sibling honeypot-detector endpoint when you specifically need raw proxy slot data (implementation/admin/beacon) rather than a security verdict.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-23T02:17:38.559Z","isFirstParty":false,"canonicalSlug":"base-eip-1967-proxy-resolver-4ba6dfe2"}