Base

Load it

import { useBlockchain, blockchains } from "@agntn/keys";

const baseChain = useBlockchain(await blockchains.base()());

There is nothing Base specific here

Base is an Ethereum L2, and for keys and addresses that means it's Ethereum. The driver is AbstractEVMBlockchain with name = "base" and coin type 60, because wallets don't give L2s their own coin type.

const privateKey = "0000000000000000000000000000000000000000000000000000000000000001";

baseChain.getAddress(baseChain.getKeyPublic(privateKey)); // 0x7E5F4552091A69125d5DfCb7b8C2659029395Bdf

Same address as Ethereum for the same key, same EIP-55 checksum, same personal_sign preamble on signMessage. Everything on the Ethereum page applies verbatim.

So why a separate driver

Two reasons. name is what the MCP tools and the lazy loader key on, so an agent can say base and mean it. And deriveHDWallet on Base still uses m/44'/60'/..., which is what every wallet does, but having the driver state it keeps that decision visible instead of implied.

If you only ever call getAddress, using the Ethereum driver for Base is fine and you won't be able to tell the difference. The funds won't either, which is the part to be careful about: an address is the same on both chains, the balance isn't.