curl --request POST \
  --url https://app.fliqr.ai/api/users/{user_id}/send_content \
  --header 'Content-Type: application/json' \
  --header 'X-ACCESS-TOKEN: <api-key>' \
  --data '
{
  "messages": [
    {
      "message": {
        "text": "Hello world"
      }
    }
  ],
  "actions": [],
  "channel": "messenger"
}
'

This response has no body data.