DOC's update on using cosmosdb as a message store/topic/log

Once CosmosDb and change feed now is advertized as sor ot messaging/event sourcing store solution there are several questions that must be fully covered in the docs:
0. What API's support change feed
1. End to end delivery guarantees. Like what happens if processor dies, or losts network connection
2. What happens when another processor steals partition lease, is that possible that severeal messages will be delivered to the old and new processor. Is that possible that both processors will be processing same messages simultaniously and so on
3. Duplicates detection. Like imagine we add new doc to the CosmosDb and got a network problem after message was successfully sent to the server. Client will have to retry the request that might cause duplicates. In RDBMS this is handled by transactions, how is that handled in CosmosDb

Ideally using cosmosdb as a message store/topic/log should have separate coverage in the docs with mentioning all typical messaging topics.