Digital Toolkit
The suite of software, templates, and resources used to create, edit, and manage a digital design project.
In practice
A digital toolkit is the full working set a designer relies on for a project: layout and drawing applications, image editors, prototyping tools, fonts, templates, plugins and shared libraries. Choosing it is a practical decision about who else must open the files and what the final output is. A small studio building a website might agree on one interface tool, one image editor and a shared font set, so files pass between people without conversion.
Often confused with Plugin
A plugin is one add-on inside a tool; a digital toolkit is the whole set of tools, plugins, templates and resources used on a project.
Try this
List every application, font and template from your last project, and mark the ones a collaborator would also need installed.