# Authenticate in System
- **METHOD**: <kbd>POST</kbd>  
- **PATH**: `/api/auth`

#### Request:
```typescript
{
  data: {
    address: string;
    alias: string;
    message: string;
    signature: string;
  };
  neverExpires: boolean;
}
```

>Explanation of Fields:  
>- To get ```data``` you should [sign some message using Lethean wallet](https://testnet-docs.lthn.io/docs/build/rpc-api/wallet-rpc-api/sign_message/) (random string)

#### Response:
```typescript
   {
      success: boolean;
      data?: string // error message 
   }
```
