IsMaster represents the document returned by db.runCommand( { isMaster: 1 } ).

IsMasterLastWrite represents the last write to the MongoDB server.

ListShards reflects the output of the MongoDB 'listShards' command.

Mongos reflects a document in the config server 'config.mongos' collection.

Config document from 'replSetGetConfig': https://docs.mongodb.com/manual/reference/command/replSetGetConfig/#dbcmd.replSetGetConfig.

Member document from 'replSetGetConfig': https://docs.mongodb.com/manual/reference/command/replSetGetConfig/#dbcmd.replSetGetConfig.

Settings document from 'replSetGetConfig': https://docs.mongodb.com/manual/reference/command/replSetGetConfig/#dbcmd.replSetGetConfig.

Response document from 'replSetGetConfig': https://docs.mongodb.com/manual/reference/command/replSetGetConfig/#dbcmd.replSetGetConfig.

Shard reflects a document in the config server 'config.shards' collection (or the 'shards' array of the 'listShards' server command).

ShardingState reflects the output of the MongoDB 'shardingState' command.

Write Concern document: https://docs.mongodb.com/manual/reference/write-concern/.