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

# refreshAuthToken

> Refreshes the Dynamic user JWT using the current session, installs the replacement, and returns it

## Function Signature

```typescript theme={"system"}
refreshAuthToken(): Promise<string>
```

Available on all chain clients (`DynamicEvmWalletClient`, `DynamicSvmWalletClient`, `DynamicBtcWalletClient`, `DynamicTonWalletClient`).

## Description

Refreshes the Dynamic user JWT using the current session and installs the new token for all subsequent API calls. Returns the new JWT so you can persist it — the previous token is superseded, so overwrite your stored copy on every call.

The server enforces a hard refresh limit through the JWT's `refreshExp` claim. Once reached, refresh fails with a 401 and the user must sign in again; refresh cannot extend a session indefinitely without the user re-approving.

The session signer passed to [authenticateJwt](/node/reference/auth/authenticate-jwt) is preserved across refreshes.

## Parameters

None.

## Returns

* **`Promise<string>`** - The new JWT, already installed on the client.

## Example

```typescript theme={"system"}
const refreshedJwt = await client.refreshAuthToken();
// Overwrite the stored JWT with refreshedJwt.
```

## Error Handling

```typescript theme={"system"}
try {
  const refreshedJwt = await client.refreshAuthToken();
} catch (error) {
  // - Not authenticated: "Client must be authenticated before making API calls.
  //   Call authenticateApiToken or authenticateJwt first."
  // - Refresh limit (refreshExp) reached or session invalid: the request fails
  //   with a 401. Run the sign-in flow again and call authenticateJwt.
  // - Cookie-auth environment: "Token refresh returned no JWT. The environment
  //   may be configured for cookie-based auth; agent flows require header-based
  //   JWTs."
  console.error('Refresh failed:', error);
}
```

## Related Functions

* [`authenticateJwt()`](/node/reference/auth/authenticate-jwt) - Install a user JWT
* [`createAuthClient()`](/node/reference/auth/create-auth-client) - Sign the user in again when the refresh limit is reached