.VSIX File Format

Introduction

A .vsix file packages an extension for Visual Studio Code or for Visual Studio. A VS Code extension may add commands, languages, themes and so on. A Visual Studio extension may add VS Packages, MEF components, templates and more.

Both kinds of file are ZIP archives that follow the Open Packaging Conventions, and both have a manifest called extension.vsixmanifest. What differs is what the manifest targets and what the rest of the package holds. A VS Code package carries the extension in a folder, normally extension/, with a package.json that says what the extension does. A Visual Studio package has no package.json.

Structure

A VS Code package has these members. A file dropped on any page of this site opens in the explorer, which shows the manifest, the tables from package.json, the README and every member of the archive.

To tell the two kinds apart, look at the manifest. A VS Code package targets Microsoft.VisualStudio.Code in its InstallationTarget and lists a Microsoft.VisualStudio.Code.Manifest asset that points to package.json. A Visual Studio package targets a Visual Studio product such as Microsoft.VisualStudio.Community, or uses the older Vsix root element.

The rest of the format is described on these pages:

• Package layout – the ZIP archive and [Content_Types].xml
• extension.vsixmanifest – the manifest VS Code’s packager writes
• package.json – the fields of a VS Code extension’s manifest
• Contribution points – what an extension can add, point by point
• Activation events – when an extension starts
• Visual Studio packages – the manifest of an extension for the IDE

Links