      specification, the default character encoding for JSON content is effectively always UTF-8.
 
      - parameter utterances: An array of `Utterance` objects that provides the input content that the service is to analyze.
-     - parameter acceptLanguage: The desired language of the response. For two-character arguments, regional variants are treated as their parent language; for example, `en-US` is interpreted as `en`.
+     - parameter contentLanguage: The language of the input text for the request: English or French. Regional variants are treated as their parent
+     language; for example, `en-US` is interpreted as `en`. The input content must match the specified language. Do not
+     submit content that contains both languages. You can use different languages for **Content-Language** and
+     **Accept-Language**. * **`2017-09-21`:** Accepts `en` or `fr`. * **`2016-05-19`:** Accepts only `en`.
+     - parameter acceptLanguage: The desired language of the response. For two-character arguments, regional variants are treated as their parent
+     language; for example, `en-US` is interpreted as `en`. You can use different languages for **Content-Language** and
+     **Accept-Language**.
      - parameter failure: A function executed if an error occurs.
      - parameter success: A function executed with the successful result.
-    */
+     */
     public func toneChat(
         utterances: [Utterance],
         acceptLanguage: String? = nil,

    }

    /**
     Analyze general purpose tone.

          Uses the general purpose endpoint to analyze the tone of your input content. The service analyzes the content for
     emotional and language tones. The method always analyzes the tone of the full document; by default, it also
     analyzes the tone of each individual sentence of the content.   You can submit no more than 128 KB of total input
     content and no more than 1000 individual sentences in JSON, plain text, or HTML format. The service analyzes the
     first 1000 sentences for document-level analysis and only the first 100 sentences for sentence-level analysis.
     Use the `POST` request method to analyze larger amounts of content in any of the available formats. Use the `GET`
     request method to analyze smaller quantities of plain text content.   Per the JSON specification, the default
     character encoding for JSON content is effectively always UTF-8; per the HTTP specification, the default encoding
     for plain text and HTML is ISO-8859-1 (effectively, the ASCII character set). When specifying a content type of
     plain text or HTML, include the `charset` parameter to indicate the character encoding of the input text; for
     example: `Content-Type: text/plain;charset=utf-8`. For `text/html`, the service removes HTML tags and analyzes only
     the textual content.

     - parameter toneInput: JSON, plain text, or HTML input that contains the content to be analyzed. For JSON input, provide an object of type `ToneInput`.
     - parameter contentType: The type of the input: application/json, text/plain, or text/html. A character encoding can be specified by including a `charset` parameter. For example, 'text/plain;charset=utf-8'.
     - parameter sentences: Indicates whether the service is to return an analysis of each individual sentence in addition to its analysis of the full document. If `true` (the default), the service returns results for each sentence.
     - parameter tones: **`2017-09-21`:** Deprecated. The service continues to accept the parameter for backward-compatibility, but the parameter no longer affects the response.   **`2016-05-19`:** A comma-separated list of tones for which the service is to return its analysis of the input; the indicated tones apply both to the full document and to individual sentences of the document. You can specify one or more of the valid values. Omit the parameter to request results for all three tones.
     - parameter contentLanguage: The language of the input text for the request: English or French. Regional variants are treated as their parent language; for example, `en-US` is interpreted as `en`. The input content must match the specified language. Do not submit content that contains both languages. You can specify any combination of languages for `contentLanguage` and `Accept-Language`. * **`2017-09-21`:** Accepts `en` or `fr`. * **`2016-05-19`:** Accepts only `en`.
     - parameter acceptLanguage: The desired language of the response. For two-character arguments, regional variants are treated as their parent language; for example, `en-US` is interpreted as `en`. You can specify any combination of languages for `Content-Language` and `acceptLanguage`.
     - parameter failure: A function executed if an error occurs.
     - parameter success: A function executed with the successful result.
    */
    public func tone(
        toneInput: ToneInput,
        contentType: String,

    /**
     Analyze customer engagement tone.

     Use the customer engagement endpoint to analyze the tone of customer service and customer support conversations.
     For each utterance of a conversation, the method reports the most prevalent subset of the following seven tones:
     sad, frustrated, satisfied, excited, polite, impolite, and sympathetic.   If you submit more than 50 utterances,
     the service returns a warning for the overall content and analyzes only the first 50 utterances. If you submit a
