/**
     * Resolves an HTTP status code to an LlmException error code.
     *
     * @param statusCode the HTTP status code
     * @return the corresponding error code
     */
    protected String resolveErrorCode(final int statusCode) {
        if (statusCode == 429) {
            return LlmException.ERROR_RATE_LIMIT;
        }
        if (statusCode == 401 || statusCode == 403) {