Skip to main content

Issue a Token

This guide covers the full MLS-01 token lifecycle in JavaScript: issuing, minting, transferring, and managing supply and authority with @mintlayer/sdk. The same workflow in Go lives in the Go guides; the wallet-cli version, which explains the underlying concepts (token id, authority address, reserve vs circulating supply), is Issue a new token.

Prerequisites: npm install @mintlayer/sdk and a connected client; see the SDK Client and account providers pages for running outside a browser.

Issuing​

import { Client } from '@mintlayer/sdk';

const client = await Client.create({ network: 'testnet' });
await client.connect();

const signedTx = await client.issueToken({
  token_ticker: 'MYTOKEN',
  number_of_decimals: 8,
  metadata_uri: 'https://example.com/mytoken.json',
  is_freezable: true,
  supply_type: 'Lockable', // 'Unlimited' | 'Lockable' | 'Fixed'
  // supply_amount: 1000000,   // required for 'Fixed'
  authority: client.getAddresses().receiving[0],
});

The authority address becomes the token authority: the key that controls future operations (minting, freezing, authority transfer). Keep it secure.

Metadata​

Publish metadata at the metadata URI following the Token Metadata Standards (MLS-01 schema) so wallets and explorers can render your token. The URI can be updated later by the authority.

Minting and unminting​

Wait for the issuance transaction to confirm first. Minting moves tokens from the reserve into circulation; unminting reverses it.

await client.mintToken({ token_id: 'tmltk1...', amount: 1000, destination: 'tmt1q...' });
await client.unmintToken({ token_id: 'tmltk1...', amount: 500 });

Transferring and burning​

await client.transfer({ to: 'tmt1q...', amount: 10, token_id: 'tmltk1...' });
await client.burn({ token_id: 'tmltk1...', amount: 25 });

Authority, freeze, and supply lock​

All management operations require the token authority key:

await client.lockTokenSupply({ token_id: 'tmltk1...' }); // irreversible
await client.freezeToken({ token_id: 'tmltk1...', is_unfreezable: false });
await client.unfreezeToken({ token_id: 'tmltk1...' });
await client.changeTokenAuthority({ token_id: 'tmltk1...', new_authority: 'tmt1q...' });
await client.changeMetadataUri({ token_id: 'tmltk1...', new_metadata_uri: 'https://...' });

Reading token state​

Tokens owned by the connected addresses are listed by client.getTokensOwned(); per-token balances via client.getBalances(). Every method above also exists as a buildX variant returning an unsigned transaction; see Transactions.