# prepareTransactionForSigning

The `prepareTransactionForSigning` method prepares a Cosmos transaction for MPC signing by creating the transaction structure and computing the hash that needs to be signed.

## Usage

```ts twoslash
// [!include ~/snippets/code/chains.ts]
// ---cut---
const { transaction, hashesToSign } =
  await cosmosChain.prepareTransactionForSigning({
    address: 'cosmos1...',
    publicKey: '0350e8...',
    messages: [
      {
        typeUrl: '/cosmos.bank.v1beta1.MsgSend',
        value: {
          fromAddress: 'cosmos1...',
          toAddress: 'cosmos1...',
          amount: [{ denom: 'uatom', amount: '1000000' }],
        },
      },
    ],
    memo: 'Token transfer',
  })
```

## Parameters

| Parameter            | Type                       | Description                                                                                                |
| -------------------- | -------------------------- | ---------------------------------------------------------------------------------------------------------- |
| `transactionRequest` | `CosmosTransactionRequest` | The transaction request object containing address, publicKey, messages, and optional memo and fee settings |

## Returns

| Property       | Type                        | Description                                |
| -------------- | --------------------------- | ------------------------------------------ |
| `transaction`  | `CosmosUnsignedTransaction` | Object containing the unsigned transaction |
| `hashesToSign` | `number[][]`                | Array of hashes that need to be signed     |