IDE-LSP for MCP

A VSCode extension that exposes IDE code intelligence capabilities through the MCP (Model Context Protocol).

As long as VSCode supports parsing a certain language, this extension can provide LSP services for that language to AI models.

中文: 中文版本

Features

• 15 MCP tools covering navigation, search, diagnostics, and refactoring preview workflows
• Standalone MCP server architecture that works across multiple VSCode windows and workspaces
• Pagination and code-context output for high-volume symbol/location queries
• Symbol validation with nearest-position suggestions when the requested symbol no longer matches the cursor position
• Auto-collapsed file and symbol structure output for large files
• Debug panel and status-bar integration for observing MCP traffic and connection state

MCP Tools

Requirements

• VSCode 1.85.0+
• Node.js 22.x for local development and packaging

Usage

Installation

1. Install the extension from VSCode Extension Marketplace, or install from a local .vsix file.

2. Start VSCode and keep the extension enabled. By default, the MCP server starts automatically on port 53221.

3. Add the following configuration to your MCP configuration file (mcp.json):

{
  "mcpServers": {
    "ide-lsp": {
      "url": "http://localhost:53221/mcp",
      "type": "http"
    }
  }
}

If you change ide-lsp-mcp.port, update the MCP server URL to match the configured port.

Notes for MCP Clients

• listOpenProjects accepts an optional projectPath; when provided, it returns workspaces whose opened project folders are inside that path.
• Pagination is available on large result sets such as references, implementations, diagnostics, and file search.

Debug Panel

• Set ide-lsp-mcp.enableDebug to true to show the MCP debug panel in the debug sidebar.
• The panel records tool name, arguments, result summary, duration, and success state for up to 500 entries.
• Double-click a log entry to open the full request and response in a read-only virtual document.
• The listOpenProjects tool runs only on the MCP server side and will not appear in the debug panel.

Commands

Settings

Behavior Notes

• getFileStruct and getSymbolStruct support maxDepth; negative values use auto mode and respect ide-lsp-mcp.maxStructLines.
• Symbol-aware tools validate symbolName and can return suggested positions if the target symbol has moved.
• getDiagnostics can temporarily activate a file when a language server only publishes diagnostics for the foreground editor; waiting is controlled by ide-lsp-mcp.diagnosticsTimeout.

Architecture

┌─────────────────┐     HTTP/SSE      ┌─────────────────┐
│   MCP Client    │ ◄──────────────► │   MCP Server    │
│  (AI Model)     │                   │ (Standalone Node.js) │
└─────────────────┘                   └────────┬────────┘
                                               │ WebSocket
                    ┌─────────────────────────┼─────────────────────────┐
                    ▼                         ▼                         ▼
             ┌─────────────┐           ┌─────────────┐           ┌─────────────┐
             │  Window 1   │           │  Window 2   │           │  Window 3   │
             │  ExtHost    │           │  ExtHost    │           │  ExtHost    │
             └─────────────┘           └─────────────┘           └─────────────┘

Documentation

• Features
• Architecture
• Project Structure
• Settings & Debugging

License

MIT