MongoDB API not recognizing or respecting indexes

Let me start off by saying I am not sure where the best place is for the team that has implemented MongoDB API on Cosmos DB but I figured this would be a good place to start.

I have a document in cosmos that is pretty basic:

```
{ "_id": ObjectId("abc"),
"created_at": {
"$date": 121219271827
},
"status": "pending",
"priority": 1
}
```

I am doing a db.collection.find({status: "pending"}).sort({"created_at":-1, "priority": -1}) and receiving the following error from CosmosDB SDK:
`The order by query does not have a corresponding composite index that it can be served from`

I added both a composite index on created_at and priority via Mongo shell but that didn't work and created a single field index on created_at and priority but still receiving the same message. Is there some guidance on how to get these indexes to be properly recognized? Currently a major blocker for us.

Best,
Dave

No repository file, test, or entry point is identified. Start by reproducing the MongoDB API query and reviewing how Cosmos DB composite and single-field indexes are created and surfaced; done means determining why the indexes are not recognized or documenting the required guidance.

Written by the indexing model from the issue text.