ACC Recipients - Who? What? Where? When? How?

In working with contracts and main-contracts endpoints, I am seeing recipients appear in the API response, however, I cannot seem to populate it with information. This value is not mentioned anywhere in the APS documents - not listed as a value in the response body for either of these endpoints, yet it exists.

I have sent a contract to actual people and it continues to remain null. When/where/how does this get populated? With what does it populated - array of objects? array of strings?

You got it, the recipients should be Not relevant, should not be used by public. I reported it back to our engineering team, we will get this fixed.