prepareFlowSigning

prepareFlowSigning

Locks in the quote and transitions the flow to the signing state. Returns the flow with quote.signingPayload containing the data to sign.

Most integrations should use submitFlowTransaction instead, which calls prepareFlowSigning automatically. Use this function directly only when you need to handle signing and broadcasting yourself (e.g., server-side signing with a custody wallet).

When to call

Call prepareFlowSigning only when executionState is quoted.

Before restoring or retrying a flow, call getFlow and check its current state.

Do not call prepareFlowSigning again after the flow reaches signing. Continue with the returned signing payload. If the transaction was submitted, call broadcastFlow with its hash. If no transaction was submitted and you need to restart, call getFlowQuote to return to quoted with a new quote. If the flow has not reached quoted yet, attach a source and get a quote first. Poll broadcasted or source_confirmed flows. If the flow is cancelled, expired, or failed, create a new flow. Calling from an unsupported state returns 409.

Usage

import { prepareFlowSigning } from '@dynamic-labs-sdk/client';

const flow = await prepareFlowSigning({
  flowId: 'your-flow-id',
  assertBalanceForGasCost: true,
  assertBalanceForTransferAmount: true,
});

const { signingPayload } = flow.quote;

Parameters

Parameter	Type	Description
flowId	string	The flow ID.
assertBalanceForGasCost	boolean (optional)	Verify the wallet has enough for gas. Returns 422 if insufficient. Default: false.
assertBalanceForTransferAmount	boolean (optional)	Verify the wallet has enough for the transfer. Returns 422 if insufficient. Default: false.

Returns

Promise<Flow> — the flow with executionState: 'signing' and quote.signingPayload populated.

The signing payload structure depends on the chain:

Chain	Fields
EVM	evmTransaction (to, data, value, gasLimit) and optional evmApproval (tokenAddress, spenderAddress, amount)
SOL, SUI	serializedTransaction (base64-encoded)
BTC	psbt (base64-encoded unsigned PSBT)
TRON	tronTransaction (rawDataHex, to, value)

Examples

Prepare with balance assertions

import { prepareFlowSigning } from '@dynamic-labs-sdk/client';

const flow = await prepareFlowSigning({
  flowId: 'your-flow-id',
  assertBalanceForGasCost: true,
  assertBalanceForTransferAmount: true,
});

Manual sign and broadcast flow

import { prepareFlowSigning, broadcastFlow } from '@dynamic-labs-sdk/client';

// 1. Prepare
const prepared = await prepareFlowSigning({ flowId: 'your-flow-id' });
const { signingPayload } = prepared.quote;

// 2. Sign with your wallet (EVM example)
const txHash = await walletClient.sendTransaction({
  to: signingPayload.evmTransaction.to,
  data: signingPayload.evmTransaction.data,
  value: BigInt(signingPayload.evmTransaction.value),
});

// 3. Broadcast
await broadcastFlow({ flowId: 'your-flow-id', txHash });

React

import { usePrepareFlowSigning } from '@dynamic-labs-sdk/react-hooks';

function PrepareButton({ flowId }) {
  const { mutate: prepare, data: flow, isPending } = usePrepareFlowSigning();

  return (
    <div>
      <button onClick={() => prepare({ flowId })} disabled={isPending}>
        {isPending ? 'Preparing...' : 'Prepare Signing'}
      </button>
      {flow?.quote?.signingPayload && <p>Ready to sign</p>}
    </div>
  );
}

Related

• Fireblocks Flow JavaScript SDK guide - End-to-end flow guide
• submitFlowTransaction - Recommended: handles prepare, sign, and broadcast
• broadcastFlow - Record the broadcast
• Signing the transaction by chain - Chain-specific signing examples