If the External Tool has been stealthed in the system, how do I add it to a site?
Stealthed tools are tools which are available in your instance, but are hidden from non-admin users when they select which tools they want to use in a site. Some institutions choose to stealth the External Tool item from all courses so that they can better control which sites have the ability to add or configure individual LTI tools. If the External Tool has been stealthed in your system, the admin user needs to manually add it to a site via the Sites tool before you can use it to configure or test an LTI item within that site.
Locate the site where you would like to add the stealthed tool.
Use the Search function to find the site you want to modify.
Click New Page.
You will see a listing of pages, or tools, currently active in the Tool Menu of the site. Click New Page to add another tool to this list.
Enter a Title.

Enter a title for the stealthed tool. The title you enter here is what will appear in the Tool Menu of the site once it has been added. You may also select the radio button for yes or no to indicate whether this is a custom title, or the default tool title.