Extension Manager
Authoring and Sharing
Interested in adding some new functionality to NetLogo by creating your own extension? Have an extension you made and want to add it to the Extension Manager? See the extension authoring page to get started.
Interface
The Extension Manager can be shown by choosing “Extensions…” from the Tools
menu. 
On the left side of the Extension Manager window, you can see a list of all
available extensions. Extensions that are already installed and up-to-date have
a green checkmark next to them. Extensions that are installed but have a newer
version available are marked with an orange arrow. Extensions that are not
installed have no indicator. Extensions have an orange exclamation point next to
them if any installation of that extension through the Extension Manager (past
or future) would be overridden by a version of the extension that is present in
the NetLogo installation’s extensions directory or in the current model’s
directory.
When an extension is selected, the text on the right side provides a detailed
description of the extension. Above the description are buttons for various
context-sensitive operations, such as installing, updating, and uninstalling.
The “Add to Code Tab” button will add the extension to the list of your model’s
extensions (for example, changing the line of code extensions [array table] to
extensions [array table web] when used for the Web extension). The “Homepage”
button will open documentation in your web browser, which will provide you with
information about the extension, a list of its primitives, and how to use them.
At the top of the window, there is a text box that can be used to filter down the list of extensions based on what you type. Along the bottom of the Extension Manager window is a button that will allow you to instantly update all of your extensions to their latest versions (if any updates are available). If NetLogo detects any extensions that have been installed outside of the Extension Manager, a “View Conflicting Libraries” button will appear at the bottom of the window, allowing you to display all of the other extensions and their locations on your computer.
Note that you can also select multiple extensions in the list with your operating system’s standard keys for performing multi-item selections (e.g. Ctrl, Shift, Command). This feature can be used to, for example, install multiple extensions all at once.