One key. Every chain.

Typed key generation, address derivation, and message signing for eight blockchains. One interface in TypeScript, the same thirteen operations over MCP, and nothing ever leaves the process.

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8
chains: 2
curves: 0
network calls: 13
MCP tools

Derivation

Keys in, addresses out

A private key is an integer. Multiply it by the generator, hash the result, encode the hash, and you have an address. Every chain is the same three steps with different rules. The panel walks the keyspace live.

secp256k1 through @noble, ed25519 through SLIP-10
Legacy, SegWit, Taproot, EIP-55, base58check, bech32
Same 32 bytes, eight chains, derived in this tab

Open the explorer

private key 1

Bitcoin · secp256k1

132-byte secretinteger in 1 … n − 1
0000000000000000000000000000000000000000000000000000000000000001
2public keyk · G, compressed, 33 bytes
0279be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798
3addresshash, then encode
- legacyP2PKH · base58check1BgGZ9tcN4rm9KBzDn7KprQz87SZ26SAMH
- segwitP2WPKH · bech32bc1qw508d6qejxtdg4y5r3zarvary0c5xw7kv8f3t4
- taprootP2TR · bech32mbc1pmfr3p9j00pfxjh0zmgp99y8zftmd3s5pmedqhyptwy6lm87hf5sspknck9

all chains in the explorer

One interface

Same calls, every chain

Every blockchain is a class with the same shape. Swap the import and the rest of the code stays. Options that a chain does not support are rejected, not ignored.

generateWallet, getAddress, signMessage on every driver
Drivers load lazily, only the chains you use ship
Custom chains extend the same abstract class

Working with keys

TSbitcoin.ts

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

const chain = useBlockchain(await blockchains.bitcoin()());
const wallet = chain.generateWallet();
const signature = chain.signMessage("hello", wallet.private);

// address of private key 1 on this chain
// bc1qw508d6qejxtdg4y5r3zarvary0c5xw7kv8f3t4

HD wallets

Mnemonic to wallet in one call

Walk a BIP39 mnemonic down a BIP44 path and get the wallet at the end of it. Paths are parsed and validated, so a hardened segment in the wrong place fails before derivation.

BIP39 mnemonics in ten languages, checksum enforced
BIP32 for secp256k1, SLIP-10 for ed25519
Bitcoin infers the address type from the purpose

Generating wallets

derivation path

BIP44 · Ethereum · test vector

mmaster/44'purpose/60'coin/0'account/0change/0index

const wallet = chain.deriveHDWallet(mnemonic, "m/44'/60'/0'/0/0");
// wallet.address
// 0x9858EfFD232B4033E47d90003D41EC34EcaEda94

Blockchains

Eight drivers, one shape

Each chain is an adapter over the shared primitives. Adding one means implementing the hashing and encoding rules, not the cryptography.

Mainnet and testnet address formats
Address validation for every chain
Sui on both curves, Cardano enterprise and stake

All blockchains

Bitcoinsecp256k1 Ethereumsecp256k1 Basesecp256k1 TRONsecp256k1 Solanaed25519 Aptosed25519 Suied25519 · secp256k1 Cardanoed25519

Agents

Thirteen tools over MCP

Everything the library does is exposed as an MCP tool with the same parameters. Point an agent at it and it derives, validates, and signs without touching the network.

Keys, mnemonics, BIP44 paths, addresses, signing
stdio server started with one command
Ambiguous or unsupported inputs are rejected with a reason

MCP server setup

toolkeys_get_address

stdio · keys mcp

request

{
  "blockchain": "bitcoin",
  "publicKey": "0279be667ef9dcbbac…f81798",
  "addressType": "segwit"
}

result

{
  "chain": "bitcoin",
  "network": "mainnet",
  "address": "bc1qw508d6qejxtdg4y5r3zarvary0c5xw7kv8f3t4"
}

Start with one command

Experimental until 1.0. Pin exact versions and keep real funds on a hardware wallet.

Read the guide Open explorer