Visual Studio SDK
The Visual Studio SDK helps you extend Visual Studio features or integrate new features into Visual Studio. You can distribute your extensions to other users, as well as to the Visual Studio Marketplace. The following are some of the ways in which you can extend Visual Studio:
Add commands, buttons, menus, and other UI elements to the IDE
Add tool windows for new functionality
Extend IntelliSense for a given language, or provide IntelliSense for new programming languages
Use light bulbs to provide hints and suggestions that help developers write better code
Enable support for a new language
Add a custom project type
Reach millions of developers via the Visual Studio Marketplace
If you've never written a Visual Studio extension before, you should find more information about these features and at Starting to Develop Visual Studio Extensions.
Installing the Visual Studio SDK
The Visual Studio SDK is an optional feature in Visual Studio setup. You can also install the VS SDK later on. For more information, see Installing the Visual Studio SDK.
What's New in the Visual Studio 2017 SDK
The Visual Studio SDK has some new features such as the VSIX v3 format as well as breaking changes which may require you to update your extension. For more information, see What's New in the Visual Studio 2017 SDK.
Visual Studio User Experience Guidelines
Get great tips for designing the UI for your extension in Visual Studio User Experience Guidelines.
You can also learn how to make your extension look great on high DPI devices with our Addressing DPI Issues topic.
Take advantage of the Image Service and Catalog for great image management and support for high DPI and theming.
Finding and Installing Existing Visual Studio Extensions
You can find Visual Studio extensions in the Extensions and Updates dialog on the Tools menu. For more information, see Finding and Using Visual Studio Extensions. You can also find extensions in the Visual Studio Marketplace
Visual Studio SDK Reference
You can find the Visual Studio SDK API reference at Visual Studio SDK Reference.
Visual Studio SDK Samples
You can find open source examples of VS SDK extensions on GitHub at Visual Studio Samples. This GitHub repo contains samples that illustrate various extensible features in Visual Studio.
Other Visual Studio SDK Resources
You can find more information in the VSX Arcana blog and a number of blogs written by Microsoft MVPs:
Creating an Extension with a Menu Command
How to: Migrate Extensibility Projects to Visual Studio 2017
FAQ: Converting Add-ins to VSPackage Extensions
Managing Multiple Threads in Managed Code
Extending Menus and Commands
Adding Commands to Toolbars
Extending and Customizing Tool Windows
Editor and Language Service Extensions
Extending User Settings and Options
Creating Custom Project and Item Templates
Extending Properties and the Property Window
Extending Other Parts of Visual Studio
Using and Providing Services
Visual Studio Isolated Shell
Shipping Visual Studio Extensions
Inside the Visual Studio SDK
Support for the Visual Studio SDK
Visual Studio SDK Reference