# eth\_getCode - Optimism

This method retrieves the EVM bytecode stored at a specific address. If the address is an externally owned account (EOA) or an empty address, it returns `'0x'`. This is useful for verifying contract deployments, analyzing contracts, and checking whether an address is a contract or an EOA. The bytecode is the compiled version of the smart contract's source code.

### Parameters

| Parameter | Type           | Description                                                    | Required |
| --------- | -------------- | -------------------------------------------------------------- | -------- |
| address   | DATA, 20 Bytes | The address to retrieve bytecode from.                         | Yes      |
| block     | QUANTITY\|TAG  | Block number in hex, or `'latest'`, `'earliest'`, `'pending'`. | Yes      |

### Request

{% tabs %}
{% tab title="cURL" %}

```bash
curl --location 'https://go.getblock.us/<ACCESS_TOKEN>' \
--header 'Content-Type: application/json' \
--data '{
   "jsonrpc": "2.0",
   "method": "eth_getCode",
    "params": [
        "0x4200000000000000000000000000000000000006",
        "latest"
    ],
    "id": "getblock.io"
}'
```

{% endtab %}

{% tab title="Axios" %}

```javascript
import axios from 'axios'
let data = JSON.stringify({
    "jsonrpc": "2.0",
   "method": "eth_getCode",
    "params": [
        "0x4200000000000000000000000000000000000006",
        "latest"
    ],
    "id": "getblock.io"
};

let config = {
  method: "post",
  maxBodyLength: Infinity,
  url: "https://go.getblock.us/<ACCESS_TOKEN>",
  headers: {
    "Content-Type": "application/json",
  },
  data: data,
};

axios
  .request(config)
  .then((response) => {
    console.log(JSON.stringify(response.data));
  })
  .catch((error) => {
    console.log(error);
  });

```

{% endtab %}

{% tab title="Request" %}

```python
import requests
import json

url = "https://go.getblock.us/<ACESS_TOKEN>"

payload = json.dumps({
   "jsonrpc": "2.0",
    "method": "eth_getCode",
    "params": [
        "0x4200000000000000000000000000000000000006",
        "latest"
    ],
    "id": "getblock.io"
})
headers = {
  'Content-Type': 'application/json'
}

response = requests.request("POST", url, headers=headers, data=payload)

print(response.text)

```

{% endtab %}

{% tab title="Rust" %}
{% code overflow="wrap" %}

```rs
#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let client = reqwest::Client::builder()
        .build()?;

    let mut headers = reqwest::header::HeaderMap::new();
    headers.insert("Content-Type", "application/json".parse()?);

    let data = r#"{
   "jsonrpc": "2.0",
   "method": "eth_getCode",
    "params": [
        "0x4200000000000000000000000000000000000006",
        "latest"
    ],
    "id": "getblock.io"
}"#;

    let json: serde_json::Value = serde_json::from_str(&data)?;

    let request = client.request(reqwest::Method::POST, "https://go.getblock.us/<ACCESS_TOKEN>")
        .headers(headers)
        .json(&json);

    let response = request.send().await?;
    let body = response.text().await?;

    println!("{}", body);

    Ok(())
}
```

{% endcode %}
{% endtab %}
{% endtabs %}

### Response

A successful response returns the following:

{% code overflow="wrap" %}

```json
{
    "jsonrpc": "2.0",
    "id": "getblock.io",
    "result": "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"
}
```

{% endcode %}

### Response Parameters

* **`id`**: A unique request identifier, matching the `id` sent in the request body.
* **`jsonrpc`**: Specifies the use of JSON-RPC version 2.0.
* **`result`**: The bytecode at the address as a hexadecimal string. Returns `'0x'` for EOAs or empty addresses.

### Use Case

The eth\_getCode method is commonly used for:

* **Contract verification**
* **EOA vs contract detection**
* **Security analysis**
* **Bytecode comparison**

#### Error handling

| Status Code | Error Message    | Cause                                                                                                                                 |
| ----------- | ---------------- | ------------------------------------------------------------------------------------------------------------------------------------- |
| 404         | Not Found        | Missing or invalid ACCESS\_TOKEN.                                                                                                     |
| -32602      | Invalid argument | <ul><li>The Address not 20 bytes or missing prefix</li><li>block hash isn't accurate or incomplete </li><li>keyword missing</li></ul> |

#### Integration with Web3

The `eth_getCode` method helps developers to:

* Detect whether a user is interacting with a contract or a wallet
* Validate deployed bytecode for audit and debugging purposes
* Build tools that identify proxies, multicall contracts, routers, and libraries
* Support trustless dapps that rely on on-chain introspection
* Ensure safe interactions by verifying contract code before sending transactions

{% tabs %}
{% tab title="Ethers.js" %}

```javascript
import { ethers } from "ethers";
const RPC_URL = "https://go.getblock.us/<ACCESS_TOKEN>";
const provider = new ethers.JsonRpcProvider(RPC_URL);
async function Call() {
  try {
     const result = await provider.send("eth_getCode",
  [
        "0x4200000000000000000000000000000000000006",
        "latest"
    ],);    
console.log("The result:", result);
    return result;
  } catch (error) {
    console.error("The error:", error);
    throw error;
  }
}
```

{% endtab %}

{% tab title="Viem" %}

```jsx
import { createPublicClient, http } from 'viem';
import { optimism } from 'viem/chains';

// Create Viem client with GetBlock
const client = createPublicClient({
  chain: optimism,
  transport: http('https://go.getblock.us/<ACCESS_TOKEN>'),
});

// Using the method through Viem
async function Call() {
    try {
        // Method-specific Viem implementation
        const result = await client.request({
          "method": "eth_getCode",
    "params": [
        "0x4200000000000000000000000000000000000006",
        "latest"
    ]
        });
        console.log('Result:', result);
        return result;
    } catch (error) {
        console.error('Viem Error:', error);
        throw error;
    }
}

```

{% endtab %}
{% endtabs %}


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.getblock.io/api-reference/optimism-op/optimism_eth_getcode.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.