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

# Error handling

> Handle API errors, configure retries, and understand error types in the UQPAY Node.js SDK.

## Error types

All API errors throw typed error classes that extend `UQPayError`:

```ts theme={null}
import {
  AuthenticationError,
  ValidationError,
  NotFoundError,
  RateLimitError,
  ServerError,
  NetworkError,
  SimulatorNotAvailableError,
} from '@uqpay/sdk'
```

Each error exposes the following fields:

| Field        | Type     | Description                  |
| ------------ | -------- | ---------------------------- |
| `message`    | `string` | Human-readable error message |
| `httpStatus` | `number` | HTTP status code             |
| `type`       | `string` | API error type string        |
| `code`       | `string` | API error code               |

## Catch errors

```ts theme={null}
try {
  const account = await client.account.accounts.retrieve('acc-123')
} catch (err) {
  if (err instanceof NotFoundError) {
    console.log('Account not found')
  } else if (err instanceof ValidationError) {
    console.log('Bad request:', err.message)
  } else if (err instanceof RateLimitError) {
    console.log('Rate limited, will retry automatically')
  } else if (err instanceof NetworkError) {
    console.log('Network error:', err.message)
  } else if (err instanceof SimulatorNotAvailableError) {
    console.log('Simulator is only available in sandbox')
  }
}
```

## Retries

The SDK automatically retries failed requests on server errors, rate limits, and network errors using exponential backoff.

Configure retries globally or per request:

```ts theme={null}
// Global — set when creating the client
const client = new UQPayClient({
  // ...
  maxRetries: 3,
})

// Per request — overrides the global setting
await client.account.accounts.retrieve('acc-123', { maxRetries: 0 })
```