The Eclipse Platform and SDK contain menu items for Help Contents, Search and Dynamic Help. A menu item to show the keyword index can be added to the help menu in an Eclipse based product by adding the following extension point to the plugin.xml file of the product plugin. The same approach will work equally well for a Rich Client application.
<extension point="org.eclipse.ui.menus">
<menuContribution locationURI="menu:help?before=group.assist">
<command commandId="org.eclipse.help.ui.indexcommand"
mnemonic="I"
style="push">
</command>
</menuContribution>
</extension>