> ## Documentation Index
> Fetch the complete documentation index at: https://docs.cow.bleu.builders/llms.txt
> Use this file to discover all available pages before exploring further.

# Proxy

> TypeScript utilities for inspecting and interacting with EIP-1967 and EIP-173 proxy contracts

# Proxy

The proxy utilities module provides tools for inspecting and interacting with EIP-1967 and EIP-173 proxy contracts used in CoW Protocol deployments.

## Functions

### implementationAddress

Retrieves the implementation contract address from an EIP-1967 proxy.

```typescript theme={null}
async function implementationAddress(
  provider: Provider,
  proxyAddress: string
): Promise<string>;
```

### ownerAddress

Fetches the admin/owner address from an EIP-1967 proxy.

```typescript theme={null}
async function ownerAddress(
  provider: Provider,
  proxyAddress: string
): Promise<string>;
```

### proxyInterface

Generates an ethers.js contract instance configured with the EIP-173 proxy admin interface.

```typescript theme={null}
function proxyInterface(
  proxyAddress: string,
  signerOrProvider: Signer | Provider
): Contract;
```

## Constants

### EIP173\_PROXY\_ABI

```typescript theme={null}
const EIP173_PROXY_ABI = [
  "function owner() view returns (address)",
  "function transferOwnership(address newOwner)",
  "event OwnershipTransferred(address indexed previousOwner, address indexed newOwner)",
];
```

## EIP-1967 Storage Slots

EIP-1967 compliance uses standardized storage slots:

| Slot           | Purpose                | Computation                                     |
| -------------- | ---------------------- | ----------------------------------------------- |
| Implementation | Logic contract address | `keccak256("eip1967.proxy.implementation") - 1` |
| Admin          | Proxy owner address    | `keccak256("eip1967.proxy.admin") - 1`          |

## Examples

### Proxy Verification

```typescript theme={null}
import { implementationAddress, ownerAddress } from "@cowprotocol/contracts";
import { ethers } from "ethers";

const provider = new ethers.providers.JsonRpcProvider("YOUR_RPC_URL");
const proxyAddress = "0x2c4c28DDBdAc9C5E7055b4C863b72eA0149D8aFE";

const impl = await implementationAddress(provider, proxyAddress);
console.log("Implementation:", impl);

const owner = await ownerAddress(provider, proxyAddress);
console.log("Owner:", owner);
```

### Ownership Transfer

```typescript theme={null}
import { proxyInterface } from "@cowprotocol/contracts";

const proxy = proxyInterface(proxyAddress, signer);
await proxy.transferOwnership(newOwnerAddress);
```