How can I add shells to the list in Run Shell Script in the Automator?
The list of these shells in this action come from this PLIST file --> "/System/Library/Automator/Run Shell Script.action/Contents/Resources/Shells.plist"

Edit this file to add others shells (need administrator's password)

    &lt;key&gt;/Users/iain/Library/Frameworks/zsh/Programs/zsh&lt;/key&gt;
&lt;dict&gt;
    &lt;key&gt;args&lt;/key&gt;
    &lt;array&gt;
        &lt;string&gt;-c&lt;/string&gt;
        &lt;string&gt;%&lt;/string&gt;
        &lt;string&gt;-&lt;/string&gt;
    &lt;/array&gt;
    &lt;key&gt;script&lt;/key&gt;
    &lt;array&gt;
        &lt;string&gt;cat&lt;/string&gt;
        &lt;string&gt;for f in "$@"&amp;#10;do&amp;#10;&amp;#09;echo "$f"&amp;#10;done&lt;/string&gt;
    &lt;/array&gt;
&lt;/dict&gt;
&lt;key&gt;/opt/rubies/ruby-2.1.2/&lt;/key&gt;
&lt;dict&gt;
    &lt;key&gt;args&lt;/key&gt;
    &lt;array&gt;
        &lt;string&gt;-e&lt;/string&gt;
        &lt;string&gt;%&lt;/string&gt;
        &lt;string&gt;--&lt;/string&gt;
    &lt;/array&gt;
    &lt;key&gt;script&lt;/key&gt;
    &lt;array&gt;
        &lt;string&gt;ARGF.each do |f|&amp;#10;&amp;#09;puts f&amp;#10;end&lt;/string&gt;
        &lt;string&gt;ARGV.each do |f|&amp;#10;&amp;#09;puts f&amp;#10;end&lt;/string&gt;
    &lt;/array&gt;
&lt;/dict&gt;