# Sign Auth Entry

URL: https://docs.blux.cc/react/usage/sign-auth-entry

Sign a Soroban authorization entry from your React app using the Blux SDK.

Use the `signAuthEntry` function from the `useBlux` hook to ask the connected wallet to sign a single **Soroban authorization entry**. It resolves to the signed entry as a base-64 XDR string.

This is a low-level building block for advanced Soroban flows — multi-party authorization, signing on behalf of a contract account, or assembling `invokeHostFunction` authorization yourself before submitting. For ordinary contract calls you don't need this: [`useWriteContract`](/react/hooks/use-write-contract) and [`sendTransaction`](/react/usage/send-transaction) handle authorization for you.

## Import
```tsx
```

## Type
```tsx
type IOptions = {
  // Network passphrase to sign against. Defaults to the active network.
  network: string;
};

const signAuthEntry: (
  authEntry: string,
  options?: IOptions,
) => Promise<string>; // the signed auth entry (base-64 XDR)
```

| Parameter | Type | Description |
|---|---|---|
| `authEntry` | `string` | Base64-encoded authorization entry (`HashIdPreimage`) to sign |
| `options.network` | `string` | Network to sign against — omit to use the active network |

## Usage
```tsx

function SignAuthEntryButton({ authEntry }: { authEntry: string }) {
  const { signAuthEntry } = useBlux();

  const handleSign = async () => {
    try {
      const signedAuthEntry = await signAuthEntry(authEntry);

      // `signedAuthEntry` is the signed entry as a base-64 XDR string.
      // Attach it to your Soroban operation's authorization before submitting.
      console.log(signedAuthEntry);
    } catch (error) {
      console.error("Signing failed:", error);
    }
  };

  return <button onClick={handleSign}>Sign Auth Entry</button>;
}
```

## Errors

`signAuthEntry` rejects with `BLUX:`-prefixed messages:

| Message | Cause |
|---|---|
| `BLUX: User is not authenticated.` | No user is logged in. |
| `BLUX: Blux modal is open elsewhere.` | Another Blux flow is already open. |
| `BLUX: Could not find the connected wallet.` | The connected wallet couldn't be resolved. |
| `BLUX: Wallet does not support signAuthEntry.` | The connected wallet has no `signAuthEntry` capability. |

<Callout type="info">
  Not every wallet supports signing auth entries. When the connected wallet lacks the capability, the call rejects with `BLUX: Wallet does not support signAuthEntry.` — handle this in your `try/catch`.
</Callout>

<Callout type="info">
  To skip the confirmation modal and build your own flow, set `showWalletUIs: false` in your `BluxProvider` configuration. The signed entry returned is identical either way.
</Callout>