TypeScript SDK: Transactions

Purpose

Guide building, signing, submitting, and simulating transactions with @aptos-labs/ts-sdk. Use the build → sign → submit → wait pattern; optionally simulate before submit.

ALWAYS

1. Call aptos.waitForTransaction({ transactionHash }) after submit – do not assume transaction is committed after signAndSubmitTransaction.
2. Use aptos.transaction.build.simple() for entry function payloads – pass sender and data: { function, functionArguments, typeArguments? }.
3. Simulate before submit for critical/high-value flows – use aptos.transaction.simulate.simple() and check success and vm_status.
4. Use the same Account instance for signer that you use for sender address when building (e.g. account.accountAddress as sender, account as signer).

NEVER

1. Do not skip waitForTransaction – submission returns when the tx is accepted, not when it is committed.
2. Do not use deprecated scriptComposer (removed in v6) – use separate transactions or batch patterns.
3. Do not use number for u64/u128/u256 in functionArguments – use bigint where required to avoid precision loss.

---

Standard flow (simple transaction)

import { Aptos, AptosConfig, Network } from "@aptos-labs/ts-sdk";

const aptos = new Aptos(new AptosConfig({ network: Network.TESTNET }));
const MODULE_ADDRESS = "0x...";

// 1. Build
const transaction = await aptos.transaction.build.simple({
  sender: account.accountAddress,
  data: {
    function: `${MODULE_ADDRESS}::counter::increment`,
    functionArguments: []
  }
});

// 2. Sign and submit
const pendingTx = await aptos.signAndSubmitTransaction({
  signer: account,
  transaction
});

// 3. Wait for commitment
const committedTx = await aptos.waitForTransaction({
  transactionHash: pendingTx.hash
});

if (!committedTx.success) {
  throw new Error(`Tx failed: ${committedTx.vm_status}`);
}

---

Build options

// With type arguments (e.g. coin type)
const transaction = await aptos.transaction.build.simple({
  sender: account.accountAddress,
  data: {
    function: "0x1::coin::transfer",
    typeArguments: ["0x1::aptos_coin::AptosCoin"],
    functionArguments: [recipientAddress, amount]
  }
});

// Optional: max gas, expiry, etc. (see SDK types for full options)
const transactionWithOptions = await aptos.transaction.build.simple({
  sender: account.accountAddress,
  data: { function: "...", functionArguments: [] },
  options: {
    maxGasAmount: 2000n,
    gasUnitPrice: 100n,
    expireTimestamp: BigInt(Math.floor(Date.now() / 1000) + 600)
  }
});

---

Simulation (before submit)

const transaction = await aptos.transaction.build.simple({
  sender: account.accountAddress,
  data: {
    function: `${MODULE_ADDRESS}::counter::increment`,
    functionArguments: []
  }
});

const [simResult] = await aptos.transaction.simulate.simple({
  signerPublicKey: account.publicKey,
  transaction
});

if (!simResult.success) {
  throw new Error(`Simulation failed: ${simResult.vm_status}`);
}
console.log("Gas used:", simResult.gas_used);

---

Sponsored transactions (fee payer)

// 1. Build with fee payer
const transaction = await aptos.transaction.build.simple({
  sender: sender.accountAddress,
  withFeePayer: true,
  data: {
    function: `${MODULE_ADDRESS}::counter::increment`,
    functionArguments: []
  }
});

// 2. Sender signs
const senderAuth = aptos.transaction.sign({
  signer: sender,
  transaction
});

// 3. Fee payer signs (different method)
const feePayerAuth = aptos.transaction.signAsFeePayer({
  signer: feePayer,
  transaction
});

// 4. Submit with both authenticators
const pendingTx = await aptos.transaction.submit.simple({
  transaction,
  senderAuthenticator: senderAuth,
  feePayerAuthenticator: feePayerAuth
});

await aptos.waitForTransaction({ transactionHash: pendingTx.hash });

---

Multi-agent transactions

const transaction = await aptos.transaction.build.multiAgent({
  sender: alice.accountAddress,
  secondarySignerAddresses: [bob.accountAddress],
  data: {
    function: `${MODULE_ADDRESS}::escrow::exchange`,
    functionArguments: [itemAddress, amount]
  }
});

const aliceAuth = aptos.transaction.sign({ signer: alice, transaction });
const bobAuth = aptos.transaction.sign({ signer: bob, transaction });

const pendingTx = await aptos.transaction.submit.multiAgent({
  transaction,
  senderAuthenticator: aliceAuth,
  additionalSignersAuthenticators: [bobAuth]
});

await aptos.waitForTransaction({ transactionHash: pendingTx.hash });

---

waitForTransaction options

const committed = await aptos.waitForTransaction({
  transactionHash: pendingTx.hash,
  options: {
    timeoutSecs: 60,
    checkSuccess: true // throw if tx failed
  }
});

---

Gas profiling

const gasProfile = await aptos.gasProfile({
  sender: account.accountAddress,
  data: {
    function: `${MODULE_ADDRESS}::module::function_name`,
    functionArguments: []
  }
});
console.log("Gas profile:", gasProfile);

---

Common mistakes

Mistake	Correct approach
Not calling waitForTransaction	Always wait and check committedTx.success
Using number for large amounts	Use bigint for u64/u128/u256 in functionArguments
Wrong signer for submit	Use the Account whose address is the sender (or fee payer / additional signer as appropriate)
Assuming scriptComposer exists	Use separate transactions or batch; scriptComposer removed in v6

---

References

• SDK: src/api/transaction.ts, src/internal/transactionSubmission.ts, src/internal/transaction.ts
• Pattern: TYPESCRIPT_SDK.md
• Related: ts-sdk-account, ts-sdk-client, ts-sdk-wallet-adapter, use-ts-sdk