Kobo Language Support for Visual Studio

Extension version 0.1.26 (Kobo language 0.1.25)

This VSIX adds .kobo editing support to Visual Studio 2022 (17.14 or later) and Visual Studio 2026 (Community, Professional, and Enterprise). It shares the Kobo language server and TextMate grammar with the VS Code extension. It provides syntax highlighting, completion, hover information, go to definition, and diagnostics. Prompt bodies remain plain text except for ${...} Kobo expressions. The editor uses the shared grammar for coloring; Visual Studio may not apply every semantic token provided by the server.

The extension does not compile Kobo itself. Kobo compilation in projects is provided by the separate thinkmine.kobo.lang.buildtools NuGet package.

Project integration and templates

When a .kobo file is added to an SDK-style C# project in a solution, the extension offers to install BuildTools 0.1.26 if it is not already installed. The prompt appears at most once per project per Visual Studio session; declining leaves the project unchanged. Installation uses the project's configured NuGet sources and reports failures in a dialog and the Visual Studio Activity Log. The package automatically includes Kobo files during project compilation. Standalone files, non-C# projects, and legacy C# project files are unaffected.

The Kobo Console Application template creates a Kobo-only net11.0 console project with a Kobo Main method. The Kobo Enabled Console Application template creates a C# net11.0 console project with a Kobo source file compiled alongside it. Both templates reference BuildTools 0.1.26. Project builds require a .NET 11 compiler host with Roslyn 5.9 or later; older .NET Framework-based Visual Studio analyzer hosts cannot run the generator. The BuildTools package also requires thinkmine.kobo.ai 0.1.26 to be available on a configured NuGet source.

Requirements

• Visual Studio 2022 17.14 or later, or Visual Studio 2026 for Windows, with the core editor
• .NET 11 runtime, with dotnet available on PATH; .NET 11 SDK to build projects

Opening a .kobo file starts the bundled language server. If it cannot start, Visual Studio shows an InfoBar; details from the server appear in the Visual Studio Activity Log. Install the .NET 11 runtime if dotnet is unavailable.

Build and install

On Windows, install the Visual Studio extension development workload and the .NET 11 SDK. Build Kobo.Lang.VisualStudio.csproj in Visual Studio 2026 or with MSBuild. The project publishes the language server into the VSIX automatically. Open the generated .vsix on a machine with a supported Visual Studio to install it, then restart Visual Studio. On macOS, use python3 build_vsix.py with the .NET 11 SDK and Mono to package the extension with the official VSSDK tool. The package includes the VSSDK-generated manifest.json and catalog.json needed by the Visual Studio Marketplace, plus project template discovery manifests. Visual Studio itself is required on Windows to test installation and editor integration.

The VSIX installation target uses stable API version 17.14 as its lower bound, which the Visual Studio Marketplace accepts and Visual Studio 2026 supports.

To publish this VSIX, choose New extension → Visual Studio in the Visual Studio Marketplace. The Visual Studio Code extension has a separate VSIX and upload category; uploading this Visual Studio VSIX as a Visual Studio Code extension is not supported.

Open a folder or individual file to use the language server. In an open folder, completion can use other Kobo files in that workspace, including unsaved open files. Dependency-specific suggestions still depend on the references known to the language server.