MCP Switch

Let your VS Code agent turn MCP servers on and off.

VS Code agents (Copilot Chat in agent mode, and other Language Model Tools clients) can't start or stop MCP servers on their own — VS Code doesn't give the model access to its MCP lifecycle commands. MCP Switch bridges that gap: it's a small extension that exposes four agent-callable tools which drive VS Code's own MCP lifecycle commands (workbench.mcp.startServer, stopServer, restartServer).

Tools

Just ask your agent: "Start the GitHub MCP server", "Turn off the database MCP", "Restart CloudTest".

Sidebar

The MCP Switch activity-bar view lists every configured server as a card with its inferred state — a green "On · N tools" pill when its tools are live in this window, "Off" when they're not — and a large Start/Stop toggle button (one button, labeled and color-coded by what it will do: green to start, red to stop) plus a Restart button and a full-width Refresh button. (It's a webview rather than a tree view because VS Code fixes tree-view inline icons at a small size extensions can't change.) The list refreshes automatically when tools appear or disappear and when any mcp.json changes.

State is tracked and inferred: VS Code exposes no authoritative per-server running state, so MCP Switch records every start/stop it dispatches in the window (authoritative for its own actions) and otherwise infers state from the window's visible tools. A server's tools are registered under its announced name, which may differ from its config label — when MCP Switch starts a server itself it remembers which tools appeared for it, so its state stays accurate on later runs. Two honest caveats: a stopped server's tools can linger in the visible set, and a server started entirely outside MCP Switch before it ever ran may show as off until it has been started through MCP Switch once.

Design principles

• Non-migrating. Your configuration stays where it is. Servers are discovered by reading the user profile mcp.json, each workspace folder's .vscode/mcp.json, and each folder's root .mcp.json. Nothing is imported, moved, rewritten, or deleted — ever.
• Stop means stop. Stopping ends the current connection. It does not disable the server, remove it, or change any setting; a later request can start it again.
• No wildcards. Every action names exactly one server. If two scopes define the same name, the tool asks for a scope or definition ID instead of guessing.
• Prompts stay human. Start/stop/restart tool calls ask for your confirmation, and VS Code's own trust and OAuth sign-in prompts remain fully interactive. The extension never auto-trusts a server and never sees or returns credentials, headers, commands, or environment values — list returns names, scopes, transports, and IDs only.
• Honest state. VS Code doesn't expose authoritative per-server running state to extensions through a stable API, so state is always labeled as what it is: dispatch results from the tools, and an inferred on/off — derived from the tools actually visible in the window — in the list tool and the sidebar.

Known limits

• Discovery covers file-configured servers (user profile, workspace folder, workspace root). Servers provided by other extensions and agent-host session servers can't be enumerated by any stable API — but they can still be started/stopped by passing their explicit definitionId, or agentHostSession + serverId for session-managed servers, to the start/stop/restart tools. An extension-provided server's definition ID is predictable: <publisher>.<extensionName>/<server label> — for example acme.my-extension/My Server. The list tool returns this formula too.
• The internal definition-ID scheme used to address config servers (mcp.config.usrlocal.<name>, mcp.config.ws<index>.<name>, workspace-dot-mcp.<index>.<name>) is VS Code-internal. It is verified against the VS Code source and current builds, but a future VS Code release could change it; the explicit-ID path will keep working.

Commands

The same actions are available to humans from the Command Palette: MCP Switch: List / Start / Stop / Restart / Toggle / Refresh MCP Server(s). Details are written to the MCP Switch output channel.

Requirements

VS Code 1.102 or later, and a language-model tool client such as GitHub Copilot Chat in agent mode for the agent-callable tools.

License

MIT