curl --request POST \
  --url https://api.voxworks.ai/api/v1/lists/{list_id}/contacts/existing \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "contact_ids": [
    "a1b2c3d4-5678-90ab-cdef-1234567890ab"
  ]
}
'

const options = {
  method: 'POST',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
  body: JSON.stringify({contact_ids: ['a1b2c3d4-5678-90ab-cdef-1234567890ab']})
};

fetch('https://api.voxworks.ai/api/v1/lists/{list_id}/contacts/existing', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

import requests

url = "https://api.voxworks.ai/api/v1/lists/{list_id}/contacts/existing"

payload = { "contact_ids": ["a1b2c3d4-5678-90ab-cdef-1234567890ab"] }
headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.text)

{
  "success": true,
  "contactsAdded": 123,
  "alreadyInListCount": 123,
  "list_contacts": [
    {}
  ]
}

{
  "success": false,
  "message": "<string>"
}

{
  "success": false,
  "message": "Invalid API key"
}

{
  "success": true,
  "message": "<string>",
  "missing_contact_ids": [
    "<string>"
  ]
}

{
  "success": false,
  "message": "Rate limit exceeded"
}

{
  "success": false,
  "message": "Internal server error"
}