Copilot CLI IDE Bridge for Visual Studio

A Visual Studio extension that enables GitHub Copilot CLI to interact with Visual Studio via the /ide command — the same way it works with VS Code.

The MCP server uses ModelContextProtocol.AspNetCore with Kestrel hosting over a Windows named pipe — ASP.NET Core handles all HTTP and SSE transport.

Copilot CLI running in an external terminal, connected to Visual Studio via /ide

Copilot CLI embedded directly inside Visual Studio as a dockable tool window

Getting Started

Prerequisites

• Visual Studio 2022 (v17.x) or Visual Studio 2026 (v18.x)
• GitHub Copilot CLI installed
• An active Copilot subscription
• .NET 10.0 SDK (for the MCP server process)

Build & Install

# Clone and build (requires MSBuild from VS — not dotnet build)
git clone https://github.com/sailro/CopilotCliIde
msbuild /restore src/CopilotCliIde/CopilotCliIde.csproj /p:Configuration=Debug

# The .vsix is produced at:
# src/CopilotCliIde/bin/Debug/CopilotCliIde.vsix

Note: The MCP server is automatically published and bundled into the VSIX during the build.

Double-click the .vsix to install, or use F5 in Visual Studio to debug in the experimental instance.

Usage

1. Open a solution in Visual Studio — the extension activates automatically
2. Launch Copilot CLI using one of:
   • Tools → Copilot CLI (Embedded Terminal) — opens a dockable terminal inside VS with Copilot CLI running (embedded via WebView2 + xterm.js)
   • Tools → Copilot CLI (External Terminal) — opens Copilot CLI in an external terminal window
   • Open a terminal manually in the solution folder
3. Run /ide in Copilot CLI — it discovers Visual Studio and connects

$ copilot
> /ide
  ✓ Connected to Visual Studio (CopilotCliIde)

Once connected, the agent can query solution info, see your selection in real time, propose diffs with Accept/Reject, and check diagnostics from the Error List.

Tip: The embedded terminal (Tools → Copilot CLI (Embedded Terminal)) is dockable — position it alongside your editor for a side-by-side workflow.

Diagnostics

The extension logs all bridge activity to a dedicated "Copilot CLI IDE" pane in the VS Output Window (View → Output). Each log entry is timestamped and includes:

• MCP tool calls received from Copilot CLI (e.g., get_selection, open_diff, read_file)
• Push notifications sent to the CLI (e.g., selection changes, diagnostics updates)

This real-time log is useful for debugging connectivity issues, verifying that the CLI can see your edits, and monitoring the bridge during active sessions.

Architecture

Copilot CLI ──(Streamable HTTP over named pipe)──▶ CopilotCliIde.Server (net10.0)
                                                        │
                                                 (StreamJsonRpc over named pipe)
                                                        │
                                                 CopilotCliIde (VS extension, net472)

• CopilotCliIde.Server (net10.0) — ASP.NET Core (Kestrel) process hosting the MCP server on a Windows named pipe via ModelContextProtocol.AspNetCore. Handles Streamable HTTP transport (POST/GET/DELETE), SSE push notifications, and session tracking. Contains 7 MCP tools in the Tools/ folder.
• CopilotCliIde (net472) — The VS extension package. Manages the connection lifecycle, subscribes to editor events, exposes VS services over StreamJsonRpc, and hosts an embedded terminal (WebView2 + ConPTY) for running Copilot CLI inside VS.
• CopilotCliIde.Shared (netstandard2.0) — Shared RPC contracts and DTOs.

Protocol

For full protocol details — discovery, transport, MCP tools, push notifications, and schemas — see doc/protocol.md.

Changelog

See CHANGELOG.md for a detailed history of changes.

License

MIT