EVM developer utilities toolbox. One call that works out what an EVM value is and converts it every useful way: an address gets its EIP-55 checksum and bytes32 form; a signature its 4-byte selector and event topic; calldata is decoded (ERC-20, NFT, permit, EIP-3009); a bytes32 becomes uint256, address and units; a number converts between wei, gwei, ether (or any decimals) and hex; text gets keccak256. Local, no network. Use for building or debugging contracts and agents.