Using-pepcli.md

@@ -2,27 +2,39 @@ The `pepcli` application is the primary command line interface (CLI) application
 
 The use of command line utilities such as `pepcli` is subject to details of the platform on which it is run. For example, a literal `*` (asterisk) parameter value must be escaped to `\*` on Linux to prevent [shell expansion](https://www.gnu.org/software/bash/manual/html_node/Shell-Expansions.html). Such details are not (extensively) covered in this documentation. Users are expected to be knowledgeable enough about their platforms to perform basic tasks and avoid common pitfalls.
 
-# Authentication
-If you are working in a desktop environment (e.g. on Windows machine), you can authenticate to PEP with:
+# General usage
+
+The `pepcli` utility must be invoked from a command line, with parameters telling it what to do. The general form of invocation is
 
 ```
-pepLogon
+pepcli [general flags] <COMMAND> [command flags] [parameters...]
 ```
 
-This will open a browser window in which you can authenticate. After that, you will remain authenticated for one day.
+Some commands have subcommands:
+```
+pepcli [general flags] <COMMAND> <SUBCOMMAND> [subcommand flags] [parameters...]
+```
 
-If you are working on a server environment, you will receive an oauth token from us. This can be passed to `pepcli`,  as explained below.
+## Command line help
+
+The `pepcli` application provides command line help if it is invoked without parameters, or with the `--help` switch. The following invocations therefore produce the same results:
 
-# General usage
-Most `pepcli` command have the following form:
 ```
-pepcli [general flags] <COMMAND> [command flags] [parameter 1] [parameter 2] [...]
+pepcli
+pepcli --help
 ```
-Some commands have subcommands:
+
+The `--help` switch is also supported by most (or all?) of `pepcli`'s commands and subcommands. This can be used to "drill down" to the command a user wishes to issue, e.g.:
+
 ```
-pepcli [general flags] <COMMAND> <SUBCOMMAND> [subcommand flags] [parameter 1] [parameter 2] [...]
+pepcli --help
+pepcli ama --help
+pepcli ama query --help
+pepcli ama query --column-group ShortPseudonyms
 ```
 
+## General flags
+
 Some of the general flags are the following:
 
 - `--oauth-token` You need this flag if you cannot use pepLogon. You will receive a token file that authenticates you to PEP. This flag takes the path to that file. After using this flag once you will remain authenticated for a day. So it's not necessary to pass this flag again. It's not a problem if you do pass it again, so when writing code that runs pepcli it's probably easiest to always pass this flag.