Tool detail

proxy

Detects EIP-1967/UUPS/Transparent proxy patterns for a contract address and returns the implementation address behind it.

Categories: Onchain data

Use when

find the implementation address behind an upgradeable proxy contract
check whether a contract address is a known proxy pattern

Not for

not a general contract-storage reader beyond proxy-slot detection
not proxy history or upgrade timeline - current implementation only

Inputs

GET path param: address (contract address, required, in the URL); query param: network (ethereum|sepolia|robinhood, optional, default ethereum)

Admitted input schema

{
  "type": "object",
  "properties": {
    "network": {
      "type": "string",
      "minLength": 0,
      "maxLength": 4096,
      "enum": [
        "ethereum",
        "sepolia",
        "robinhood"
      ],
      "default": "ethereum"
    }
  },
  "required": [],
  "additionalProperties": false
}

Endpoint

Method: GET
URL: https://api.onesource.io/api/chain/proxy/{address}

Payment

Protocol: x402
Listed price: 0.005 USDC per call on Base (eip155:8453)
Payment method: exact
Network: eip155:8453
Asset: 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913

Listed terms are catalog metadata. The caller supplies inputs and calls the tool outside Onelayer. If payment is required, the caller uses a compatible wallet to pay.

Source

Directory: Coinbase x402 Bazaar
Record: GET https://api.onesource.io/api/chain/proxy/:address
Retrieved: 2026-09-30T20:37:07.382Z
Catalog file SHA-256: 6837ccddf886f0007cf3727ea9d27faaa5047b51b4f425345c554ce1c271a524
Catalog built: 2026-09-30T22:31:58.034Z