For full manual transaction signing, you need to provide the sender's private key.
Treat the private key as a secret and never expose it to the public.
import { makeSTXTokenTransfer } from '@stacks/transactions';const privateKey = randomPrivateKey(); // see "Private Keys & Wallets" pageconst tx = await makeSTXTokenTransfer({ recipient: 'ST39MJ145BR6S8C315AG2BD61SJ16E208P1FDK3AK', // which address you are sending to amount: 10000, // tokens, denominated in micro-STX anchorMode: 'any', senderKey: privateKey,});