> ## Documentation Index
> Fetch the complete documentation index at: https://crossmint-devin-1787949784-wallet-docs-two-concept-model.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# CrossmintOtpVerifyCallback

> Flutter Type Alias

**Type Alias**

Called by non-custodial signers to verify the OTP the user entered.

```dart theme={null}
typedef CrossmintOtpVerifyCallback = Future<void> Function(String otp)
```