Google Contacts API vs People API

Question

I'm having a problem with the 2 APIs above. Given the next scenario: I have 2 different google accounts. One that doesn't use Google+ and a second account that uses Google+

When using Contacts API on the first account that doesn't use Google+ I can see all my contacts:

GET /m8/feeds/contacts/<email>/full

Same for the second account that uses Google+.

When I'm using People API for the first account that doesn't use Google+, I'm getting an empty response (actually I'm getting just the next sync token:

GET https://people.googleapis.com/v1/people/me/connections

With the next scope:

https://www.googleapis.com/auth/contacts

Returns:

{
  "nextSyncToken": "CMe6...."
}

The same call for the second account (with Google+) works like a charm

The only difference between the 2 accounts is Google+, is it possible that People API only works for accounts with Google+? Or is it something else that I'm missing

Answer 1

I found the difference between the 2 APIs and it has nothing to do with the fact that one of the accounts is connected to Google+ or not

People API will only fetch the contacts that are under the account "My contacts" contacts, while Contacts API will also fetch the other contacts lists ("Other contacts", "Most contacts", ...)