MCP Watchdog

Repository: github.com/vaibhav11123/mcp-watchdog

VS Code / Cursor extension that runs a parallel health layer over MCP servers defined in .vscode/mcp.json: periodic pings, exponential backoff reconnects, and an extra check when the window regains focus (helpful after sleep).

This does not replace the editor’s built-in MCP integration. It opens its own MCP client connections only to monitor reachability and latency.

Install

After install, reload the window if commands or views do not appear.

Requirements

• VS Code or Cursor with a compatible engine: this manifest declares engines.vscode: ^1.105.0 (adjust if you need a different floor after testing).
• A workspace folder that contains .vscode/mcp.json with a top-level servers object (same shape VS Code uses for MCP).
• In multi-root workspaces, only the first folder is used when resolving mcp.json and ${workspaceFolder}.

Quick start

1. Add .vscode/mcp.json (see example below). You may use ${workspaceFolder} in args, cwd, env values, and URLs — MCP Watchdog expands it like VS Code.
2. Open that folder. MCP Watchdog shows in the activity bar → Servers; the status bar shows MCP: n/n.
3. Optional: View → Output → MCP Watchdog for detailed logs.

Screenshots

Status bar — aggregate health (MCP: healthy / total) on the bottom right:

Servers view — per-server state and last ping latency in the MCP Watchdog activity bar sidebar:

Example mcp.json

{
  "servers": {
    "memory": {
      "type": "stdio",
      "command": "npx",
      "args": ["-y", "@modelcontextprotocol/server-memory"]
    },
    "remote": {
      "type": "http",
      "url": "http://localhost:3000/mcp",
      "headers": { "Authorization": "Bearer YOUR_TOKEN" }
    }
  }
}

Security: only configure servers you trust. This extension runs command (e.g. npx, node) and opens HTTP(S) URLs you specify.

Commands

• MCP Watchdog: Show Server Status — Quick pick with per-server state.
• MCP Watchdog: Reconnect All Servers
• MCP Watchdog: Reconnect Server…
• MCP Watchdog: Open Servers View — Focus the Servers tree.

Settings (mcpWatchdog.*)

Changes apply on reload or when mcp.json is reloaded; live settings refresh without reload is not implemented yet.

Privacy & data

• No bundled analytics or telemetry from this extension.
• Traffic goes to your configured MCP servers only (stdio child processes and HTTP clients you define in mcp.json).
• Do not commit secrets inside mcp.json in shared repos; use environment variables or secret stores appropriate to your team.

Known limitations

• Workspace mcp.json only (first root folder). User-global MCP config paths are not read.
• Independent of the editor’s MCP UI: native MCP may show different state until the next Watchdog ping.
• HTTP transport may combine SDK-level reconnection with Watchdog-level retries.
• Malformed mcp.json: invalid JSON shows an error notification; fix the file and save.

Troubleshooting

See Screenshots above for the Marketplace / README visuals.

Development

npm install
npm run compile
npm run build

• Run Extension / Run Extension (mcp-watchdog-test workspace) from .vscode/launch.json.
• Fixture: mcp-watchdog-test/ (optional; not shipped in VSIX).
• Headless smoke: npm run smoke.

See CHANGELOG.md.

Ship checklist (maintainers)

1. publisher — Currently mcp-watchdog; change in package.json if you use a different Marketplace publisher id.
2. repository / bugs / homepage — Update in package.json if you publish under a different GitHub org or repo name.
3. version — Bump per semver; summarize in CHANGELOG.md.
4. README — Screenshots, confirm engine range matches lowest editor you support.
5. Publish — npx @vscode/vsce login <publisher> then npx @vscode/vsce publish (after npm run build).

npm run build
npx @vscode/vsce package
# install locally to verify
cursor --install-extension mcp-watchdog-<version>.vsix

License

MIT — see LICENSE.

Security: see SECURITY.md.