Using-pepcli.md

@@ -49,12 +49,32 @@ pepcli --oauth-token /PATH/TO/OAuthToken.json --client-working-directory /PATH/T
 
 Other general flags exist, but are intended for use by developers of the PEP system. While mentioned in `pepcli`'s command line help, they are not further documented here.
 
-# PEP Commands
-## See which columns you have access to
+## List of commands
+
+The commands supported by `pepcli` are listed below. Follow hyperlinks to read more detailed documentation on each of the commands. A categorization [by task and/or audience](#by-task) is also available.
+
+- [`query`](#query) provides information on the PEP environment.
+
+## By task
+
+General purpose:
+
+- [`query`](#query) provides information on the PEP environment.
+
+# Commands supported by `pepcli`
+
+## query
+
+Use the `pepcli query` command to query the system. It currently only supports a single sub-command, which lists the columns accessible to you:
+
 ```
 pepcli query column-access
 ```
-This will list the column groups and the columns you have access to, as well as whether you have read and/or write access
+
+The output will include all columns and column groups accessible to you, as well as whether you have read and/or write access. Note that such access depends on the access group for which you are enrolled. Enroll for a specific access group:
+
+- either by means of a prior call to `pepLogon`,
+- or by passing an appropriate [OAuth token](#general-flags) to `pepcli`.
 
 ## List data
 You can list data e.g. as follows: