> ## Documentation Index
> Fetch the complete documentation index at: https://docs.dzap.io/llms.txt
> Use this file to discover all available pages before exploring further.
# Build Transaction
> Compile a trade quote into ready-to-sign transaction calldata.
Takes the route(s) you selected from `/v1/quotes` (via `protocol`) and returns transaction data ready to sign and submit.
### Body
Wallet address sending the transaction.
Address to receive refunds.
Source chain ID for every item in `data`.
`false` for standard execution; `true` for the gasless/intent flow.
Array of trade legs to build.
Amount in the source token's smallest unit.
Source token contract address.
Source token decimals.
Destination token contract address.
Destination token decimals.
Destination chain ID.
Provider ID selected from the quote response (e.g. `recommendedSource`).
Address to receive the destination tokens.
Slippage tolerance, in percent.
Route-specific data echoed back from the quote.
Pre-signed permit data for the source token.
Request private/MEV-protected execution.
Skip gas estimation for a faster build.
Set `true` if Permit2 approval already exists for every token in `data`.
Required for Bitcoin-chain transactions only.
### Response - non-gasless (`gasless: false`)
`"success"` when the build succeeds.
Unique build/transaction ID - use for status polling and broadcasting.
Chain where the transaction is to be executed.
Chain-specific payload - shape depends on the chain type.
Hex-encoded calldata.
Contract to call.
Native value to send, in wei.
PSBT inputs.
PSBT outputs.
`"bolt11"`
Array of `{ domain, types, primaryType, message }` typed-data payloads to sign.
`false`.
Echoes whether private/MEV-protected execution was used.
Per-pair summary keyed by pair ID.
Provider-specific extra data (shape varies).
`@deprecated` - top-level mirror of `transaction.data` for EVM chains.
`@deprecated` - top-level mirror of `transaction.from`.
`@deprecated` - top-level mirror of `transaction.to`.
`@deprecated` - top-level mirror of `transaction.value`.
`@deprecated` - top-level mirror of `transaction.gasLimit`.
`{ blockhash, lastValidBlockHeight }`, present for Solana transactions.
`{ inputs, outputs, feeRate }`, present for Bitcoin transactions.
`{ paymentRequestType: "bolt11", paymentRequest, paymentExpiry }`, present for Bitcoin Lightning.
`Record>`.
`Record` - refreshed destination amounts keyed by pair ID.
### Response - gasless (`gasless: true`)
`"success"`.
Intent ID - pass to `/v1/gasless/executeTx` once signed.
Typed-data payload to sign.
Absent for pure EIP-2612/bridge-only intents.
`"bridge"`
`"swap"`
Same shape as the non-gasless response above.
`true`.
`false`.
### Examples
```bash curl theme={null}
curl -X POST https://api.dzap.io/v1/buildTx \
-H "Content-Type: application/json" \
-d '{
"sender": "0x99BCEBf44433E901597D9fCb16E799a4847519f6",
"refundee": "0x99BCEBf44433E901597D9fCb16E799a4847519f6",
"fromChain": 42161,
"gasless": false,
"data": [
{
"amount": "1000000",
"srcToken": "0xaf88d065e77c8cC2239327C5EDb3A432268e5831",
"destToken": "0x4200000000000000000000000000000000000006",
"toChain": 8453,
"protocol": "across",
"recipient": "0x99BCEBf44433E901597D9fCb16E799a4847519f6",
"slippage": 1
}
]
}'
```
```ts SDK theme={null}
const request = {
sender: userAccount,
refundee: userAccount,
fromChain: 42161,
gasless: false,
data: [
{
amount: '1000000',
srcToken: '0xaf88d065e77c8cC2239327C5EDb3A432268e5831',
destToken: '0x4200000000000000000000000000000000000006',
toChain: 8453,
protocol: 'across',
recipient: userAccount,
slippage: 1,
},
],
};
// Build only:
const buildResponse = await dzap.buildTradeTxn(request);
// Or build + sign + execute in one call:
const result = await dzap.trade({ request, signer });
```
```json 200 theme={null}
{
"status": "success",
"txId": "0xabc123...",
"chainId": 42161,
"transaction": {
"from": "0x99BCEBf44433E901597D9fCb16E799a4847519f6",
"data": "0x...",
"to": "0x1d46863e3592745008b5CbbAC12014F67329A9b8",
"value": "0",
"gasLimit": "350000"
},
"gasless": false,
"private": false,
"quotes": {
"across": {
"provider": "across",
"destAmount": "300000000000000",
"minDestAmount": "298500000000000",
"duration": "90"
}
},
"additionalInfo": {},
"updatedQuotes": {}
}
```
Use the `txId` to poll `/v1/status` once the transaction has been signed and sent.