The issue is that Visual Studio 2022/2025 does not currently support custom Copilot Chat Agents (like the @spec-kit participant) because the Visual Studio extension ecosystem for Copilot Chat is not yet as extensible as VS Code's "Chat Participant" API.

While Spec Kit is optimized for VS Code, it remains IDE-agnostic at its core since it relies on Markdown files and a CLI. You can use it effectively in a .NET project within Visual Studio by combining the Specify CLI with Visual Studio's Context Mentions.

Using Spec Kit in Visual Studio

1. Manage Specs via the CLI

Use the Visual Studio Terminal (Ctrl + ~) to run Spec Kit commands. This ensures your specs.md and tasks.md files are generated and kept in sync with your solution.

# Initialize or sync your specs directly in the VS terminal
npx specify sync

2. Referencing Tasks in Copilot Chat

To perform the final implementation, use the # (Mention) feature in the Visual Studio Copilot Chat pane. This allows you to feed the tasks.md file directly into the prompt context so Copilot understands your requirements.

Example Prompt:

"Using the context in #tasks.md, please implement the OrderService logic in OrderService.cs. Follow the architectural constraints defined in #specs.md."

Are you using the specify CLI for your initial spec generation, or are you looking for a way to automate the "implementation" phase more directly within the Visual Studio editor?