What potential pitfalls should be considered when working with external APIs in PHP, such as the Feiertags API mentioned in the forum thread?

When working with external APIs in PHP, potential pitfalls to consider include handling errors and exceptions, ensuring proper authentication and security measures, and dealing with rate limits and throttling to avoid being blocked by the API provider.

try {
    // Make API request
    $response = file_get_contents('https://api.example.com/data');
    
    // Process API response
    // ...
} catch (Exception $e) {
    // Handle API errors
    echo 'Error: ' . $e->getMessage();
}