> ## Documentation Index
> Fetch the complete documentation index at: https://docs.biconomy.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Building Instructions

> Build transaction instructions for execution

## buildComposable

Build a composable instruction with support for runtime injection, conditions, and automatic encoding.

```typescript theme={null}
const instruction = await account.buildComposable(options);
```

### Instruction Types

| Type                  | Description                 |
| --------------------- | --------------------------- |
| `default`             | Generic contract call       |
| `transfer`            | ERC-20 token transfer       |
| `approve`             | ERC-20 approval             |
| `nativeTokenTransfer` | Native token (ETH) transfer |

***

## Default Type

Call any contract function.

```typescript theme={null}
const instruction = await account.buildComposable({
  type: "default",
  data: {
    chainId: number;
    to: Address;
    abi: Abi;
    functionName: string;
    args: any[];
    value?: bigint;
    gasLimit?: bigint;
    conditions?: Condition[];
  }
});
```

### Parameters

| Parameter             | Type          | Required | Description                                                                                                                           |
| --------------------- | ------------- | -------- | ------------------------------------------------------------------------------------------------------------------------------------- |
| `chainId`             | `number`      | Yes      | Target chain                                                                                                                          |
| `to`                  | `Address`     | Yes      | Contract address                                                                                                                      |
| `abi`                 | `Abi`         | Yes      | Contract ABI                                                                                                                          |
| `functionName`        | `string`      | Yes      | Function to call                                                                                                                      |
| `args`                | `any[]`       | Yes      | Function arguments                                                                                                                    |
| `value`               | `bigint`      | No       | Native value to send                                                                                                                  |
| `gasLimit`            | `bigint`      | No       | Custom gas limit                                                                                                                      |
| `conditions`          | `Condition[]` | No       | Execution conditions                                                                                                                  |
| `simulationOverrides` | `Overrides`   | No       | Per-instruction simulation overrides (e.g. token balances); see [Utilities – Simulation](/sdk-reference/utilities#simulation-options) |

### Example

```typescript theme={null}
const swap = await account.buildComposable({
  type: "default",
  data: {
    chainId: 8453,
    to: UNISWAP_ROUTER,
    abi: UniswapAbi,
    functionName: "exactInputSingle",
    args: [{
      tokenIn: USDC,
      tokenOut: WETH,
      amountIn: parseUnits("100", 6),
      amountOutMinimum: 0n,
      recipient: account.addressOn(8453, true),
      fee: 500,
      sqrtPriceLimitX96: 0n
    }]
  }
});
```

***

## Transfer Type

Simplified ERC-20 token transfer.

```typescript theme={null}
const instruction = await account.buildComposable({
  type: "transfer",
  data: {
    chainId: number;
    tokenAddress: Address;
    recipient: Address;
    amount: bigint | RuntimeValue;
    conditions?: Condition[];
  }
});
```

### Example

```typescript theme={null}
const transfer = await account.buildComposable({
  type: "transfer",
  data: {
    chainId: 8453,
    tokenAddress: USDC,
    recipient: "0x...",
    amount: parseUnits("50", 6)
  }
});
```

***

## Approve Type

Simplified ERC-20 approval.

```typescript theme={null}
const instruction = await account.buildComposable({
  type: "approve",
  data: {
    chainId: number;
    tokenAddress: Address;
    spender: Address;
    amount: bigint | RuntimeValue;
  }
});
```

### Example

```typescript theme={null}
const approve = await account.buildComposable({
  type: "approve",
  data: {
    chainId: 8453,
    tokenAddress: USDC,
    spender: UNISWAP_ROUTER,
    amount: parseUnits("100", 6)
  }
});
```

***

## Native Token Transfer

Send ETH or native tokens.

```typescript theme={null}
const instruction = await account.buildComposable({
  type: "nativeTokenTransfer",
  data: {
    chainId: number;
    to: Address;
    value: bigint | RuntimeValue;
  }
});
```

### Example

```typescript theme={null}
const sendEth = await account.buildComposable({
  type: "nativeTokenTransfer",
  data: {
    chainId: 8453,
    to: "0x...",
    value: parseEther("0.1")
  }
});
```

***

## Bridge Operations

To bridge tokens (e.g. via Across Protocol), use `type: "default"` and encode the bridge protocol's contract call directly. See the [Across integration guide](/new/integration-guides/bridges-and-solvers/integrate-across) for a complete example.

```typescript theme={null}
const bridge = await account.buildComposable({
  type: "default",
  data: {
    chainId: 42161,                               // Source chain
    to: ACROSS_SPOKE_POOL,                         // Bridge contract
    abi: acrossSpokePoolAbi,                       // Bridge ABI
    functionName: "depositV3",
    args: [
      account.addressOn(42161, true),              // depositor
      account.addressOn(8453, true),               // recipient
      USDC_ARBITRUM,                               // inputToken
      USDC_BASE,                                   // outputToken
      parseUnits("100", 6),                        // inputAmount
      outputAmount,                                // outputAmount (from bridge quote API)
      8453,                                        // destinationChainId
      zeroAddress,                                 // exclusiveRelayer
      quoteTimestamp,                              // quoteTimestamp
      fillDeadline,                                // fillDeadline
      0,                                           // exclusivityDeadline
      "0x"                                         // message
    ]
  }
});
```

<Info>
  Bridge operations use the same `type: "default"` as any other contract call. Get bridge parameters (output amount, timestamps, deadlines) from the bridge protocol's quote API before building the instruction.
</Info>

***

## build (Simple)

Build a simple instruction without composability.

```typescript theme={null}
const instruction = await account.build({
  type: "nativeTokenTransfer",
  data: {
    chainId: 8453,
    to: "0x...",
    value: 1n,
    lowerBoundTimestamp: Math.floor(Date.now() / 1000),
    upperBoundTimestamp: Math.floor(Date.now() / 1000) + 300
  }
});
```

***

## Time Bounds

Add time constraints to instructions:

```typescript theme={null}
const instruction = await account.buildComposable({
  type: "default",
  data: {
    chainId: 8453,
    to: "0x...",
    abi: [...],
    functionName: "doSomething",
    args: [],
    lowerBoundTimestamp: Math.floor(Date.now() / 1000) + 60,  // Start in 1 min
    upperBoundTimestamp: Math.floor(Date.now() / 1000) + 300  // Expire in 5 min
  }
});
```

| Parameter             | Description                            |
| --------------------- | -------------------------------------- |
| `lowerBoundTimestamp` | Earliest execution time (unix seconds) |
| `upperBoundTimestamp` | Latest execution time (unix seconds)   |