Before we start, a warning. This is was vibecoded in like 30 minutes. It probably doesn't work for every chain. I will make fixes as I encounter bugs. Its still useful IMO so do with it what you will.

ABI Fetch

A simple CLI tool to fetch contract ABIs from various blockchain explorers.

Features

• Support for multiple EVM-compatible networks
• Fetch contract ABIs by address
• Automatic contract name extraction
• Simple command-line interface

Installation

1. Clone the repository:

git clone https://github.com/yourusername/abi-fetch.git
cd abi-fetch

2. Install dependencies:

bun install

Usage

Setting up your API keys

You need to set your API keys as environment variables. You can get API keys from the respective block explorers:

• Etherscan
• BscScan
• PolygonScan
• BaseScan
• And others...

Set your API keys in the .env file:

ETHERSCAN_API_KEY=your_api_key
# Optional: Use a separate API key for Base chain
BASESCAN_API_KEY=your_basescan_api_key

Or set them directly in your shell:

export ETHERSCAN_API_KEY=your_api_key
export BASESCAN_API_KEY=your_basescan_api_key  # Optional

Running the application

Fetch an ABI by providing just the contract address. The tool will automatically check all supported chains:

bun run src/index.ts 0xBB9bc244D798123fDe783fCc1C72d3Bb8C189413

The tool will search across all supported chains and display the contract name for each instance found. If the contract is found on multiple chains, you'll be prompted to choose which chain to save the ABI from.

The ABI will be automatically saved to a JSON file named after the contract (or the address if the contract name is not available).

Logging

The application uses a configurable logging system. You can control the log level using the LOG_LEVEL environment variable:

# Set log level to DEBUG for more verbose output
LOG_LEVEL=DEBUG bun run src/index.ts 0xBB9bc244D798123fDe783fCc1C72d3Bb8C189413

# Set log level to ERROR to only show errors
LOG_LEVEL=ERROR bun run src/index.ts 0xBB9bc244D798123fDe783fCc1C72d3Bb8C189413

Available log levels:

• DEBUG: Detailed information for debugging
• INFO: General information about the application's progress
• WARN: Warning messages for potentially harmful situations
• ERROR: Error messages for serious problems
• NONE: Disable all logging

Available Networks

The tool supports many EVM-compatible networks, including:

• Ethereum Mainnet
• Base
• Optimism
• Arbitrum
• Polygon
• BNB Smart Chain
• And many more testnets

Run the application without arguments to see a list of available networks:

bun run src/index.ts

Development

Run in development mode with hot reloading:

bun run dev

Build the application:

bun run build

License

MIT