Update simpleid-tool documentation

Author: kelvinmo

docs/2/simpleid-tool.md

@@ -9,15 +9,34 @@ eleventyNavigation:
     order: 40
 ---
 
-
 `simpleid-tool` is a command-line tool that performs various maintenance functions.
 
 ## Installing     {#installing}
 
 The tool can be installed using Composer:
 
 ```shell
-composer require simpleid/simpleid-tool:dev-master
+composer require simpleid/simpleid-tool
+```
+
+## Basic usage    {#basic}
+
+`simpleid-tool` contains a collection of different commands.  The basic syntax for running a command is as follows:
+
+```shell
+php simpleid-tool.phar [command] [options]
+```
+
+You can list the available commands using the `list` command:
+
+```shell
+php simpleid-tool.phar list
+```
+
+You can get help on each command by using the `help` command:
+
+```shell
+php simpleid-tool.phar help [command]
 ```
 
 ## Encoding passwords    {#passwd}
@@ -57,3 +76,14 @@ php simpleid-tool.phar migrate-user [example.identity]
 The tool will then migrate as much of the data in the identity file as it can into a new SimpleID 2 user file, which is displayed.
 
 Note that in most cases, the password stored in a SimpleID 1 identity file will *not* meet the password requirements for SimpleID 2.  In these cases you will need to re-encode your password (e.g. via [simpleid-tool](#passwd)) insert it into the new user file.
+
+## Calling SimpleID API endpoints {#api}
+`simpleid-tool` can be used to call endpoints made available by the SimpleID API.  This can be invoked using the following command:
+
+```shell
+php simpleid-tool.phar api -d [simpleid-dir] -- [route] [params ...]
+```
+
+`[simpleid-dir]` should be replaced with the location of the `www` directory of the SimpleID installation (i.e where `index.php` is located. 
+
+The `[route]` and `[params]` parameters should be replaced with the API endpoint and GET parameters, using the syntax set out in [Fat-Free Framework documentation](https://fatfreeframework.com/3.9/routing-engine#RoutinginCLImode).  If you are using the shell syntax, note that you will need to add a `--` before specifying the endpoint parameters, so that those parameters are not interpreted by `simpleid-tool`.