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

# DeepL Write API Service Specification Updates

The DeepL Pro API (v2 endpoint only) also includes a text improvement function. This function is only available to users with a DeepL API Pro subscription type.

The text improvement function provides the following functionality:

<table>
  <thead />

  <tbody>
    <tr>
      <td>Text</td>
      <td>Text to be improved. Only text encoded in accordance with the documentation is supported.</td>
    </tr>

    <tr>
      <td>Target language</td>

      <td>
        <p>The language in which your improvements are provided can be one of the following:</p>

        <ul>
          <li>`DE` (German)</li>
          <li>`EN-GB` (British English)</li>
          <li>`EN-US` (American English)</li>
          <li>`ES` (Spanish)</li>
          <li>`FR` (French)</li>
          <li>`IT` (Italian)</li>
          <li>`PT-BR` (Brazilian Portuguese)</li>
          <li>`PT-PT` (Portuguese)</li>
        </ul>
      </td>
    </tr>
  </tbody>
</table>

The text improvement function returns the following representation of the processing result:

<table>
  <thead />

  <tbody>
    <tr>
      <td>Text</td>
      <td>The improved text</td>
    </tr>

    <tr>
      <td>Target language</td>
      <td>The target language specified by the user</td>
    </tr>

    <tr>
      <td>Detected source language</td>
      <td>The detected source language of the text provided in the request.</td>
    </tr>
  </tbody>
</table>