# @mysten/sui (/integrations/sui)



`@mysten/sui` is Sui's official TypeScript SDK. butr discovers and manages the
wallet; `@mysten/sui` owns the RPC client (`SuiClient`) and the transaction
builder (`Transaction`); the wallet's Wallet Standard features supply signing
and execution.

## Read state with `SuiClient` [#read-state-with-suiclient]

`SuiClient` talks to a Sui full node directly — point it at a network and read
balances without routing through the wallet:

```ts
import { SuiClient } from "@mysten/sui/client";

const client = new SuiClient({ url: "https://fullnode.testnet.sui.io:443" });

const { totalBalance } = await client.getBalance({ owner: wallet.account.walletAddress });
const sui = `${Number(totalBalance) / 1_000_000_000} SUI`; // MIST → SUI
```

## Sign a message [#sign-a-message]

The Sui adapter wires `signMessage` directly — call it on the connector and get
the signature bytes back:

```ts
const message = new TextEncoder().encode("Hello from butr + @mysten/sui");
const { signature } = await wallet.connector.signMessage(message);
// `signature` is a Uint8Array — render as hex for display.
```

## Build and send a transaction [#build-and-send-a-transaction]

Build with `@mysten/sui`'s `Transaction` programmable-transaction builder, then
hand the object to butr's `sendTx` — the Sui adapter routes it through the
wallet's `sui:signAndExecuteTransaction` feature, which signs **and** broadcasts:

```ts
import { Transaction } from "@mysten/sui/transactions";

const tx = new Transaction();
tx.setSender(wallet.account.walletAddress);
// A no-op self-transfer: split 0 MIST off the gas coin, send it back.
const [coin] = tx.splitCoins(tx.gas, [0]);
tx.transferObjects([coin], wallet.account.walletAddress);

const digest = await wallet.connector.sendTx(tx);
// digest → look up on https://suiscan.xyz/testnet/tx/<digest>
```

<Callout type="info">
  Unlike EVM/SVM, you don't broadcast separately — Sui wallets expose
  `sui:signAndExecuteTransaction`, which signs and submits in one step. `sendTx` resolves to the
  transaction digest, not raw signed bytes. For sign-only flows (no broadcast), use
  `signTransaction` instead.
</Callout>

<Callout type="info">
  **Source:** `apps/demo-with-sui/src/app.tsx` in the [butr
  repository](https://github.com/pedroapfilho/usebutr/tree/main/apps/demo-with-sui). Targets Sui
  testnet. Run `pnpm dev --filter=demo-with-sui` → `http://localhost:5180`.
</Callout>