update command descriptions

source/includes/ref-toc-command-administration.yaml

@@ -44,27 +44,27 @@ description: "Returns the :term:`md5` hash for files stored using :term:`GridFS`
 ---
 name: ":dbcommand:`dropIndexes`"
 file: /reference/command/dropIndexes
-description: "Removes one or all indexes from a collection."
+description: "Removes indexes from a collection."
 ---
 name: ":dbcommand:`fsync`"
 file: /reference/command/fsync
 description: "Flushes pending writes to the storage layer and locks the database to allow backups."
 ---
 name: ":dbcommand:`clean`"
 file: /reference/command/clean
-description: "Internal command that obtains a write lock on the database."
+description: "Internal command."
 ---
 name: ":dbcommand:`connPoolSync`"
 file: /reference/command/connPoolSync
-description: "Internal command."
+description: "Internal command to flush connection pool."
 ---
 name: ":dbcommand:`compact`"
 file: /reference/command/compact
 description: "Defragments a collection and rebuilds the indexes."
 ---
 name: ":dbcommand:`collMod`"
 file: /reference/command/collMod
-description: "Sets flags on a collection."
+description: "Add flags to collection to modify the behavior of MongoDB."
 ---
 name: ":dbcommand:`reIndex`"
 file: /reference/command/reIndex

source/includes/ref-toc-command-aggregation.yaml

@@ -1,6 +1,6 @@
 name: ":dbcommand:`aggregate`"
 file: /reference/command/aggregate
-description: "Performs a query using the :doc:`aggregation framework </core/aggregation>` pipeline."
+description: "Performs :doc:`aggregation tasks </core/aggregation>` such as group using the aggregation framework."
 ---
 name: ":dbcommand:`count`"
 file: /reference/command/count
@@ -16,5 +16,5 @@ description: "Groups documents in a collection by the specified key and performs
 ---
 name: ":dbcommand:`mapReduce`"
 file: /reference/command/mapReduce
-description: "Performs map-reduce style data aggregation."
+description: "Performs :doc:`map-reduce </core/map-reduce>` aggregation for large data sets."
 ...

source/includes/ref-toc-command-diagnostic.yaml

@@ -8,7 +8,7 @@ description: "Internal command to support sharding."
 ---
 name: ":dbcommand:`driverOIDTest`"
 file: /reference/command/driverOIDTest
-description: "This is an internal command for testing purposes."
+description: "Internal command to convert OID to string."
 ---
 name: ":dbcommand:`listCommands`"
 file: /reference/command/listCommands
@@ -72,11 +72,11 @@ description: "Returns raw usage statistics for each database in the :program:`mo
 ---
 name: ":dbcommand:`indexStats`"
 file: /reference/command/indexStats
-description: "Experimental command, that collects and aggregates statistics on all indexes."
+description: "Experimental command that collects and aggregates statistics on all indexes."
 ---
 name: ":dbcommand:`whatsmyuri`"
 file: /reference/command/whatsmyuri
-description: "Internal diagnostic command."
+description: "Internal command that returns the uri."
 ---
 name: ":dbcommand:`getLog`"
 file: /reference/command/getLog

source/includes/ref-toc-command-internal.yaml

@@ -4,31 +4,31 @@ description: "Internal command."
 ---
 name: ":dbcommand:`_recvChunkAbort`"
 file: /reference/command/recvChunkAbort
-description: "Internal command. Do not call directly."
+description: "Internal command to abort chunk migration. Do not call directly."
 ---
 name: ":dbcommand:`_recvChunkCommit`"
 file: /reference/command/recvChunkCommit
-description: "Internal command. Do not call directly."
+description: "Internal command to commit migration. Do not call directly."
 ---
 name: ":dbcommand:`_recvChunkStart`"
 file: /reference/command/recvChunkStart
-description: "Internal command. Do not call directly."
+description: "Internal command at the start of migration. Do not call directly."
 ---
 name: ":dbcommand:`_recvChunkStatus`"
 file: /reference/command/recvChunkStatus
-description: "Internal command. Do not call directly."
+description: "Internal command to get chunk migration status. Do not call directly."
 ---
 name: ":dbcommand:`_replSetFresh`"
 file: /reference/command/replSetFresh
-description: "Internal command that supports replica set functionality."
+description: "Internal command called by a node seeking election."
 ---
 name: ":dbcommand:`mapreduce.shardedfinish`"
 file: /reference/command/mapreduce.shardedfinish
 description: "Internal command that supports :term:`map-reduce` in :term:`sharded cluster` environments."
 ---
 name: ":dbcommand:`_transferMods`"
 file: /reference/command/transferMods
-description: "Internal command. Do not call directly."
+description: "Internal command to transfer mods to destination. Do not call directly."
 ---
 name: ":dbcommand:`replSetHeartbeat`"
 file: /reference/command/replSetHeartbeat
@@ -40,7 +40,7 @@ description: "Internal command that supports replica set functionality."
 ---
 name: ":dbcommand:`_migrateClone`"
 file: /reference/command/migrateClone
-description: "Internal command. Do not call directly."
+description: "Internal command that supports chunk migration. Do not call directly."
 ---
 name: ":dbcommand:`replSetElect`"
 file: /reference/command/replSetElect
@@ -52,5 +52,5 @@ description: "Internal command that reports on write back operations."
 ---
 name: ":dbcommand:`writebacklisten`"
 file: /reference/command/writebacklisten
-description: "Internal command."
+description: "Internal command that opens a long poll to relay writes back after migration."
 ...

source/includes/ref-toc-command-replication.yaml

@@ -40,5 +40,5 @@ description: "Displays information about this member's role in the replica set,
 ---
 name: ":dbcommand:`getoptime`"
 file: /reference/command/getoptime
-description: "Internal command to support replication."
+description: "Internal command to support replication, returns the optime."
 ...

source/includes/ref-toc-command-sharding.yaml

@@ -8,7 +8,7 @@ description: "Adds a :term:`shard` to a :term:`sharded cluster`."
 ---
 name: ":dbcommand:`checkShardingIndex`"
 file: /reference/command/checkShardingIndex
-description: "Internal command that supports sharding."
+description: "Internal command that validates index on shard key."
 ---
 name: ":dbcommand:`enableSharding`"
 file: /reference/command/enableSharding
@@ -24,15 +24,15 @@ description: "Starts the process of removing a shard from a sharded cluster."
 ---
 name: ":dbcommand:`getShardMap`"
 file: /reference/command/getShardMap
-description: "Internal command that supports sharding."
+description: "Internal command returns shard information."
 ---
 name: ":dbcommand:`getShardVersion`"
 file: /reference/command/getShardVersion
-description: "Internal command that supports sharding."
+description: "Internal command that returns the term:`config server <config database>` version."
 ---
 name: ":dbcommand:`setShardVersion`"
 file: /reference/command/setShardVersion
-description: "Internal command that supports sharding."
+description: "Internal command to sets the term:`config server <config database>` version."
 ---
 name: ":dbcommand:`shardCollection`"
 file: /reference/command/shardCollection
@@ -44,23 +44,23 @@ description: "Reports whether the :program:`mongod` is a member of a sharded clu
 ---
 name: ":dbcommand:`unsetSharding`"
 file: /reference/command/unsetSharding
-description: "Internal command that supports sharding."
+description: "Internal command to reset shard connection info."
 ---
 name: ":dbcommand:`split`"
 file: /reference/command/split
 description: "Creates a new :term:`chunk`."
 ---
 name: ":dbcommand:`splitChunk`"
 file: /reference/command/splitChunk
-description: "Internal command. Instead use the methods :method:`sh.splitFind()` and :method:`sh.splitAt()`."
+description: "Internal command to split chunk. Instead use the methods :method:`sh.splitFind()` and :method:`sh.splitAt()`."
 ---
 name: ":dbcommand:`splitVector`"
 file: /reference/command/splitVector
-description: "Internal command that supports meta-data operations in sharded clusters."
+description: "Internal command that determines split points."
 ---
 name: ":dbcommand:`medianKey`"
 file: /reference/command/medianKey
-description: "Internal command."
+description: "Deprecated internal command. See splitVector."
 ---
 name: ":dbcommand:`moveChunk`"
 file: /reference/command/moveChunk