curl --request POST \
  --url https://api.deepl.com/v2/write/rephrase \
  --header 'Authorization: <api-key>' \
  --header 'Content-Type: application/json' \
  --data '{
  "text": [
    "this is a example sentence to imprve"
  ],
  "target_lang": "de",
  "writing_style": "academic",
  "tone": "confident"
}'

{
  "improvements": [
    {
      "detected_source_language": "en",
      "text": "This is a sample sentence to improve."
    }
  ]
}