Hi, i’m new to webhooks and i don’t understand one moment. When i try to send "description": "{{101496900__description}}" webhook returns “400 Bad Request”

{
  "embeds": 
   
    {
      "title": "{{101496900__title}}",
      "description": "{{101496900__description}}",
      "timestamp": "2020-10-12T07:35:27.385Z",
      "image": {
        "url": "{{101496900__raw__enclosure__@url}}"
      }
    }
  ]
}

but if i change {{101496900__description}} to {{101496900__link}} or any random text everything works fine.

{
  "embeds": 
  "
    {
      "title": "{{101496900__title}}",
      "description": "{{101496900__link}}",
      "timestamp": "2020-10-12T07:35:27.385Z",
      "image": {
        "url": "{{101496900__raw__enclosure__@url}}"
      }
    }
  ]
}

But it’s not for all sites, one site send description without errors with the same code

{
  "embeds": 
  d
    {
      "title": "{{101742728__title}}",
      "description": "{{101742728__description}} \n\n Читать далее - {{101742728__link}}",
      "timestamp": "2020-10-12T07:35:27.385Z",
      "footer": {
        "text": "{{101742728__raw__creator}}"
      },
      "image": {
        "url": "{{101742728__raw__enclosure__@url}}"
      }
    }
  ]
}