IDE Index MCP Server

A JetBrains IDE plugin that exposes an MCP (Model Context Protocol) server, enabling AI coding assistants like Claude, Codex, Cursor, and Windsurf to leverage the IDE's powerful indexing and refactoring capabilities.

Fully tested: IntelliJ IDEA, PyCharm, WebStorm, GoLand, RustRover, Android Studio, PhpStorm May work (untested): RubyMine, CLion, DataGrip

IDE Index MCP Server provides AI coding assistants with access to the IDE's powerful code intelligence features through the Model Context Protocol (MCP).

Features

Multi-Language Support Advanced tools work across multiple languages based on available plugins:

• Java & Kotlin - IntelliJ IDEA, Android Studio
• Python - PyCharm (all editions), IntelliJ with Python plugin
• JavaScript & TypeScript - WebStorm, IntelliJ Ultimate, PhpStorm
• Go - GoLand, IntelliJ IDEA Ultimate with Go plugin
• PHP - PhpStorm, IntelliJ Ultimate with PHP plugin
• Rust - RustRover, IntelliJ IDEA Ultimate with Rust plugin, CLion

Universal Tools (All JetBrains IDEs)

• Find References - Locate all usages of any symbol across the project
• Go to Definition - Navigate to symbol declarations
• Code Diagnostics - Access errors, warnings, and quick fixes
• Index Status - Check if code intelligence is ready
• Sync Files - Force sync VFS/PSI cache after external file changes
• Build Project - Trigger IDE build with structured error/warning output (disabled by default)
• Find Class - Fast class/interface search by name with camelCase matching
• Find File - Fast file search by name using IDE's file index
• Search Text - Text search using IDE's pre-built word index
• Read File - Read file content by path or qualified name, including library sources (disabled by default)
• Open File - Open a file in the editor with optional navigation (disabled by default)
• Get Active File - Get currently active editor file(s) with cursor position (disabled by default)

Extended Tools (Language-Aware) These tools activate based on installed language plugins:

• Type Hierarchy - Explore class inheritance chains
• Call Hierarchy - Trace method/function call relationships
• Find Implementations - Discover interface/abstract implementations
• Symbol Search - Find by name with fuzzy/camelCase matching (disabled by default)
• Find Super Methods - Navigate method override hierarchies
• File Structure - View hierarchical file structure like IDE's Structure view (disabled by default)

Refactoring Tools

• Rename Refactoring - Safe renaming with automatic related element renaming (getters/setters, overriding methods) - works across ALL languages, fully headless
• Reformat Code - Reformat using project code style with import optimization (disabled by default)
• Safe Delete - Remove code with usage checking (Java/Kotlin only)
• Java to Kotlin Conversion - Convert Java to Kotlin using Intellij's built-in converter (Java only)

Why Use This Plugin?

Unlike simple text-based code analysis, this plugin gives AI assistants access to:

• True semantic understanding through the IDE's AST and index
• Cross-project reference resolution that works across files and modules
• Multi-language support - automatically detects and uses language-specific handlers
• Safe refactoring operations with automatic reference updates and undo support

Perfect for AI-assisted development workflows where accuracy and safety matter.

Table of Contents

• Installation
• Quick Start
• Client Configuration
• Available Tools
• Multi-Project Support
• Tool Window
• Error Codes
• Requirements
• Contributing

Installation

Using the IDE built-in plugin system

Settings/Preferences > Plugins > Marketplace > Search for "IDE Index MCP Server" > Install

Using JetBrains Marketplace

Go to JetBrains Marketplace and install it by clicking the Install to ... button.

Manual Installation

Download the latest release and install it manually: Settings/Preferences > Plugins > ⚙️ > Install plugin from disk...

Quick Start

1. Install the plugin and restart your JetBrains IDE
2. Open a project - the MCP server starts automatically with IDE-specific defaults:
   • IntelliJ IDEA: intellij-index on port 29170
   • PyCharm: pycharm-index on port 29172
   • WebStorm: webstorm-index on port 29173
   • Other IDEs: See IDE-Specific Defaults
3. Configure your AI assistant using the "Install on Coding Agents" button (easiest) or manually
4. Use the tool window (bottom panel: "Index MCP Server") to copy configuration or monitor commands
5. Change port (optional): Click "Change port, disable tools" in the toolbar or go to Settings > Tools > Index MCP Server

Using the "Install on Coding Agents" Button

The easiest way to configure your AI assistant:

1. Open the "Index MCP Server" tool window (bottom panel)
2. Click the prominent "Install on Coding Agents" button on the right side of the toolbar
3. A popup appears with two sections:
   • Install Now - For Claude Code CLI and Codex CLI: Runs the installation command automatically
   • Copy Configuration - For other clients: Copies the JSON config to your clipboard
4. For "Copy Configuration" clients, paste the config into the appropriate config file

Client Configuration

Claude Code (CLI)

Use the "Install on Coding Agents" button in the tool window, or run this command (adjust name and port for your IDE):

# IntelliJ IDEA
claude mcp add --transport http intellij-index http://127.0.0.1:29170/index-mcp/streamable-http --scope user
 
# PyCharm
claude mcp add --transport http pycharm-index http://127.0.0.1:29172/index-mcp/streamable-http --scope user
 
# WebStorm
claude mcp add --transport http webstorm-index http://127.0.0.1:29173/index-mcp/streamable-http --scope user

Options:

• --scope user - Adds globally for all projects
• --scope project - Adds to current project only

To remove: claude mcp remove <server-name> (e.g., claude mcp remove intellij-index)

Codex CLI

Use the "Install on Coding Agents" button in the tool window, or run this command (adjust name and port for your IDE):

# IntelliJ IDEA
codex mcp add intellij-index --url http://127.0.0.1:29170/index-mcp/streamable-http
 
# PyCharm
codex mcp add pycharm-index --url http://127.0.0.1:29172/index-mcp/streamable-http
 
# WebStorm
codex mcp add webstorm-index --url http://127.0.0.1:29173/index-mcp/streamable-http

To remove: codex mcp remove <server-name> (e.g., codex mcp remove intellij-index)

Cursor

Add to .cursor/mcp.json in your project root or ~/.cursor/mcp.json globally (adjust name and port for your IDE):

{
  "mcpServers": {
    "intellij-index": {
      "url": "http://127.0.0.1:29170/index-mcp/streamable-http"
    }
  }
}

Windsurf

Add to ~/.codeium/windsurf/mcp_config.json (adjust name and port for your IDE):

{
  "mcpServers": {
    "intellij-index": {
      "serverUrl": "http://127.0.0.1:29170/index-mcp/streamable-http"
    }
  }
}

VS Code (Generic MCP)

{
  "mcp.servers": {
    "intellij-index": {
      "url": "http://127.0.0.1:29170/index-mcp/streamable-http"
    }
  }
}

Note: Replace the server name and port with your IDE's defaults. See IDE-Specific Defaults below.

IDE-Specific Defaults

Each JetBrains IDE has a unique default port and server name to allow running multiple IDEs simultaneously without conflicts:

Tip: Use the "Install on Coding Agents" button in the tool window - it automatically uses the correct server name and port for your IDE.

Available Tools

The plugin provides 21 MCP tools organized by availability. Tools marked (disabled by default) can be enabled in Settings > Tools > Index MCP Server.

Universal Tools

These tools work in all supported JetBrains IDEs.

Extended Tools (Language-Aware)

These tools activate based on available language plugins:

Java-Specific Refactoring Tools

Note: Refactoring tools modify source files. All changes support undo via Ctrl/Cmd+Z.

Tool Availability by IDE

Fully Tested:

May Work (Untested):

Note: Navigation tools activate when language plugins are present. GoLand and RustRover have 4 navigation tools (no ide_find_implementations or ide_find_super_methods due to language semantics). PhpStorm has 5 (no ide_file_structure). The rename and reformat tools work across all languages. ide_convert_java_to_kotlin is available only in IntelliJ IDEA and Android Studio, requires both Java and Kotlin plugins, and is disabled by default.

For detailed tool documentation with parameters and examples, see USAGE.md.

Multi-Project Support

When multiple projects are open in a single IDE window, you must specify which project to use with the project_path parameter:

{
  "name": "ide_find_references",
  "arguments": {
    "project_path": "/Users/dev/myproject",
    "file": "src/Main.kt",
    "line": 10,
    "column": 5
  }
}

If project_path is omitted:

• Single project open: That project is used automatically
• Multiple projects open: An error is returned with the list of available projects

Workspace Projects

The plugin supports workspace projects where a single IDE window contains multiple sub-projects as modules with separate content roots. The project_path parameter accepts:

• The workspace root path
• A sub-project path (module content root)
• A subdirectory of any open project

When an error occurs, the response includes all available sub-projects so AI agents can discover the correct paths to use.

Tool Window

The plugin adds an "Index MCP Server" tool window (bottom panel) that shows:

• Server Status: Running indicator with server URL and port
• Project Name: Currently active project
• Command History: Log of all MCP tool calls with:
  • Timestamp
  • Tool name
  • Status (Success/Error/Pending)
  • Parameters and results (expandable)
  • Execution duration

Tool Window Actions

Error Codes

JSON-RPC Standard Errors

Custom MCP Errors

Settings

Configure the plugin at Settings > Tools > Index MCP Server:

Requirements

• JetBrains IDE 2025.1 or later (any IDE based on IntelliJ Platform)
• JVM 21 or later
• MCP Protocol 2025-03-26 (primary Streamable HTTP), with 2024-11-05 legacy SSE compatibility

Supported IDEs

Fully Tested:

• IntelliJ IDEA (Community/Ultimate)
• Android Studio
• PyCharm (Community/Professional)
• WebStorm
• GoLand
• RustRover
• PhpStorm

May Work (Untested):

• RubyMine
• CLion
• DataGrip

The plugin uses standard IntelliJ Platform APIs and should work on any IntelliJ-based IDE, but has only been tested on the IDEs listed above.

Architecture

The plugin runs a custom embedded Ktor CIO HTTP server with dual MCP transports:

Streamable HTTP Transport (Primary, MCP 2025-03-26)

AI Assistant ──────► POST /index-mcp/streamable-http (initialize)
                     ◄── HTTP 200 + Mcp-Session-Id
             ──────► POST /index-mcp/streamable-http (requests/notifications)
                     ◄── JSON-RPC response or HTTP 202 Accepted
             ──────► DELETE /index-mcp/streamable-http
                     ◄── HTTP 200                    (session terminated)

Legacy SSE Transport (MCP Inspector, older clients)

AI Assistant ──────► GET /index-mcp/sse              (establish SSE stream)
                     ◄── event: endpoint             (receive POST URL with sessionId)
             ──────► POST /index-mcp?sessionId=x     (JSON-RPC requests)
                     ◄── HTTP 202 Accepted
                     ◄── event: message              (JSON-RPC response via SSE)

This dual approach:

• Primary MCP transport - Streamable HTTP per MCP 2025-03-26
• MCP Inspector compatible - Legacy SSE transport per MCP 2024-11-05
• Configurable port - IDE-specific default port, changeable in settings
• Works with any MCP-compatible client
• Single server instance across all open projects

Contributing

Contributions are welcome! Please:

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Run tests: ./gradlew test
5. Submit a pull request

Development Setup

# Build the plugin
./gradlew build
 
# Run IDE with plugin installed
./gradlew runIde
 
# Run tests
./gradlew test
 
# Run plugin verification
./gradlew runPluginVerifier

License

This project is licensed under the Apache License 2.0 - see the LICENSE file for details.

Plugin based on the IntelliJ Platform Plugin Template.