The /contacts api endpoint will provide exactly what you need. Here are some params that you can pass to /contacts (there are many more parameters available):
-
ids(the Contact ID) -
listid(the List ID) -
status(their subscription status)
Example 1:
Make a GET call to: https://{{yourAccountName}}.api-us1.com/api/3/contacts?ids=14&listid=2&status=2
…returns all contacts with the id of 14 subscribed to List with id 2 and a subscription status of 2
Example 2:
A GET call to: https://{{yourAccountName}}.api-us1.com/api/3/contacts?listid=2
…returns all contacts in list id 2
Here’s what those status codes mean