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

# Callbacks

<Note>
  **This page has been updated for Wallets SDK V1.** If you are using the previous version,
  see the [previous version docs](/wallets/v0/overview) or the [V1 migration guide](/wallets/guides/migrate-to-v1).
</Note>

> **Callbacks** = `object`

Defined in: [packages/wallets/src/wallets/types.ts:175](https://github.com/Crossmint/crossmint-sdk/blob/main/packages/wallets/src/wallets/types.ts#L175)

## Properties

### onAuthRequired()?

> `optional` **onAuthRequired**: (`signerType`, `signerLocator`, `needsAuth`, `sendOtp`, `verifyOtp`, `reject`) => `Promise`\<`void`>

Defined in: [packages/wallets/src/wallets/types.ts:178](https://github.com/Crossmint/crossmint-sdk/blob/main/packages/wallets/src/wallets/types.ts#L178)

#### Parameters

| Parameter       | Type                          |
| --------------- | ----------------------------- |
| `signerType`    | `"email"` \| `"phone"`        |
| `signerLocator` | `string`                      |
| `needsAuth`     | `boolean`                     |
| `sendOtp`       | () => `Promise`\<`void`>      |
| `verifyOtp`     | (`otp`) => `Promise`\<`void`> |
| `reject`        | () => `void`                  |

#### Returns

`Promise`\<`void`>

***

### onTransactionStart()?

> `optional` **onTransactionStart**: () => `Promise`\<`void`>

Defined in: [packages/wallets/src/wallets/types.ts:177](https://github.com/Crossmint/crossmint-sdk/blob/main/packages/wallets/src/wallets/types.ts#L177)

#### Returns

`Promise`\<`void`>

***

### onWalletCreationStart()?

> `optional` **onWalletCreationStart**: () => `Promise`\<`void`>

Defined in: [packages/wallets/src/wallets/types.ts:176](https://github.com/Crossmint/crossmint-sdk/blob/main/packages/wallets/src/wallets/types.ts#L176)

#### Returns

`Promise`\<`void`>