Maya has a script reference, but it doesn't have all the command options. (Example: polySeparate)
You can see a list of all options by passing the name of the command you want to look up to the help command.
import maya.cmds as cmds
print cmds.help("polySeparate")
When I run the above in Maya's script editor, I get the following:
wrap up: polySeparate [flags] [String...]
Flags:
-e -edit
-q -query
-cch -caching on|off
-ch -constructionHistory on|off
-fzn -frozen on|off
-n -name String
-nds -nodeState Int
-o -object on|off
-rs -removeShells on|off
-sss -separateSpecificShell Int (multi-use)