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, including symbol-based definition/reference lookup
• 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
• Markdown - heading outlines in file structure for IDEs with the bundled Markdown plugin

Universal Tools (All Supported 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
• Reload Project - Refresh linked Maven/Gradle build models after dependency or build-file changes (disabled by default)
• Import Modules - Import external Maven project directories as modules for cross-project code intelligence and refactoring (disabled by default)
• Open Workspace - Scan a root directory for Maven projects, or provide an explicit list of Maven project paths, and open them all in one IntelliJ window with full cross-project code intelligence (disabled by default)
• 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
• Symbol Search - Find code symbols by name with IntelliJ Go to Symbol matching (disabled by default)
• Search Text - Text search using IntelliJ Find in Files (substring and regex matching)
• 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
• Find Super Methods - Navigate method override hierarchies
• File Structure - View hierarchical file structure like IDE's Structure view, including PHP Structure View trees and Markdown heading outlines; shows start and end line for each element (disabled by default)

Refactoring Tools

• Rename Refactoring - Safe renaming with automatic related element renaming (getters/setters, overriding methods) - works across ALL languages, fully headless
• Move File - Move files with IDE-aware reference and package updates when supported
• Reformat Code - Reformat using project code style with import optimization (disabled by default)
• Optimize Imports - Remove unused imports and organize imports without reformatting (disabled by default)
• Edit Member - Replace an entire member declaration (signature + body) with new content (Java/Kotlin, disabled by default)
• Insert Member - Insert a new member at a structural position (Java/Kotlin, disabled by default)
• Replace Member - Replace method body or field initializer only, preserving the signature (Java/Kotlin, 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)

Project Lifecycle Management

When working across many projects simultaneously, idle ones consume memory unnecessarily and leave editors open for no reason. Lifecycle management sleeps and wakes projects based on window focus and MCP activity. It is opt-in — disabled by default; turn on "Enable lifecycle management" in Settings → Tools → Index MCP Server, after which no further configuration is required.

• Automatic sleep/wake - Projects move from active → background (Power Save on) → dormant (editors closed, PSI cache freed) → closed (fully unloaded), and auto-reopen transparently on the next MCP call
• ide_project_status - Combined snapshot of every open and managed project
• ide_set_project_mode / ide_get_project_modes - Explicit mode control
• ide_release_project - Unenroll a project from lifecycle management
• ide_lifecycle_log - Timestamped event log with trigger reasons, for diagnosing unexpected behaviour. The ring buffer is always active; file output enables via Help → Diagnostic Tools → Debug Log Settings

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
• Headless and remote development support - starts in regular IDE windows, JetBrains remote development sessions, and headless automation runs
• Safe refactoring operations with automatic reference updates and undo support

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

Security

The server binds to 127.0.0.1 with no authentication — any local process can call its tools with your IDE's file access. On a single-user dev machine that's the same trust boundary your shell already has; on a shared machine, it's worth weighing before you enable the write tools.

Table of Contents

• Installation
• Quick Start
• Community Integrations
• Client Configuration
• Available Tools
• Multi-Project Support
• Lifecycle Management
• Tool Window
• Error Codes
• Settings
• Requirements
• Architecture
• Contributing
• License

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

Community Integrations

• opencode-jetbrains-index - a third-party integration for OpenCode that uses this plugin

Disclaimer: This repository is not maintained by me. Please use its own issue tracker for integration-specific issues and support.

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 --scope user intellij-index http://127.0.0.1:29170/index-mcp/streamable-http

# PyCharm
claude mcp add --transport http --scope user pycharm-index http://127.0.0.1:29172/index-mcp/streamable-http

# WebStorm
claude mcp add --transport http --scope user webstorm-index http://127.0.0.1:29173/index-mcp/streamable-http

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:

IDE	Server Name	Default Port
IntelliJ IDEA	intellij-index	29170
Android Studio	android-studio-index	29171
PyCharm	pycharm-index	29172
WebStorm	webstorm-index	29173
GoLand	goland-index	29174
PhpStorm	phpstorm-index	29175
RubyMine	rubymine-index	29176
CLion	clion-index	29177
RustRover	rustrover-index	29178
DataGrip	datagrip-index	29179
Aqua	aqua-index	29180
DataSpell	dataspell-index	29181
Rider	rider-index	29182

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 50 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.

Tool	Description
ide_find_references	Find all references to a symbol across the entire project
ide_find_definition	Find the definition/declaration location of a symbol
ide_find_class	Search for classes/interfaces by name with camelCase/substring/wildcard matching
ide_find_file	Search for files by name using IDE's file index
ide_find_symbol	Search for symbols (classes, methods, fields, functions) by name with IntelliJ Go to Symbol matching (disabled by default)
ide_search_text	Text search using IntelliJ Find in Files with context filtering (substring and regex matching)
ide_diagnostics	Analyze file problems with fresh editor diagnostics for open files or public batch diagnostics for closed files, plus optional build/test results; intentions are best-effort
ide_index_status	Check if the IDE is in dumb mode or smart mode
ide_sync_files	Force sync IDE's virtual file system and PSI cache with external file changes
ide_reload_project	Force-reload Maven or Gradle build model after modifying pom.xml/build.gradle (disabled by default)
ide_import_modules	Import external Maven project directories as modules into the current IntelliJ window (disabled by default, requires Maven plugin)
ide_open_workspace	Scan a root directory for Maven projects, or provide an explicit module list, and open them all in one IntelliJ window with full cross-project code intelligence (disabled by default, requires Maven plugin)
ide_build_project	Build project using IDE's build system (JPS, Gradle, Maven) with structured errors (disabled by default)
ide_run_tests	Run tests via the IDE's run configuration infrastructure; structured pass/fail results read from the IDE's test runner (works with any framework — JUnit, TestNG, pytest, Jest, Go test, PHPUnit). Class/method FQN targeting is Java/Kotlin-only; other languages pass an existing run-config name (disabled by default)
ide_read_file	Read file content by path or qualified name, including library/jar sources (disabled by default)
ide_get_active_file	Get the currently active file(s) in the editor with cursor position (disabled by default)
ide_open_file	Open a file in the editor with optional line/column navigation (disabled by default)
ide_set_power_save_mode	Enable or disable IDE Power Save Mode — suspends background inspections while keeping the index and all code intelligence operational (disabled by default)
ide_close_project	Close an open project window and free its memory — refuses to close the last open project (disabled by default)
ide_open_project	Open a project by absolute path and wait until indexing completes (configurable timeout); returns immediately if already open (disabled by default)
ide_install_plugin	Install a plugin zip into the IDE, replacing any existing version — auto-detects build/distributions/*.zip when no path is given (disabled by default)
ide_restart	Restart the IDE — terminates the MCP connection; call after ide_install_plugin (disabled by default)
ide_refactor_rename	Rename a symbol or file and update all references across the project (all languages; use targetType for explicit file mode)
ide_move_file	Move a file to a new directory, applying language-aware reference/package updates when the IDE provides a semantic move backend
ide_reformat_code	Reformat code using project code style with import optimization (disabled by default)
ide_optimize_imports	Optimize imports without reformatting code (disabled by default)
ide_structural_search_replace	Pattern-based code search and transformation using IntelliJ's Structural Search and Replace engine (Java, Kotlin) (disabled by default)
ide_create_file	Create a new source file with content, immediately indexed by IntelliJ — use instead of Write for .java, .kt, .ts, .tsx, .py files (disabled by default)
ide_replace_text_in_file	Find and replace text in a file using IntelliJ's Document API — changes immediately visible to index and PSI without ide_sync_files (disabled by default)
ide_change_signature	Change method signature with automatic caller updates (Java only) (disabled by default)
ide_edit_member	Replace an entire member declaration (signature + body) with new content (Java, Kotlin) (disabled by default)
ide_insert_member	Insert a new member at a structural position in a class or file (Java, Kotlin) (disabled by default)
ide_replace_member	Replace a method body or field initializer only, preserving the signature (Java, Kotlin) (disabled by default)

Extended Tools (Language-Aware)

These tools activate based on available language plugins:

Tool	Description	Languages
ide_type_hierarchy	Get the complete type hierarchy (supertypes and subtypes)	Java, Kotlin, Python, JS/TS, Go, PHP, Rust
ide_call_hierarchy	Analyze method call relationships (callers or callees)	Java, Kotlin, Python, JS/TS, Go, PHP, Rust
ide_find_implementations	Find all implementations of an interface or abstract method	Java, Kotlin, Python, JS/TS, PHP, Rust
ide_find_super_methods	Find the full inheritance hierarchy of methods that a method overrides/implements	Java, Kotlin, Python, JS/TS, PHP
ide_file_structure	Get hierarchical file structure (similar to IDE's Structure view) with start and end line numbers for each element (disabled by default)	Java, Kotlin, Python, JS/TS, PHP, Markdown

PHP file structure support requires the PHP plugin and is available in PhpStorm or IntelliJ IDEA Ultimate with the PHP plugin enabled.

Java-Specific Tools

Tool	Description
ide_list_tests	List all test methods/classes discovered by the IDE's test framework extension points (JUnit, TestNG, etc.) (disabled by default, requires Java plugin)
ide_convert_java_to_kotlin	Convert Java files to Kotlin using IntelliJ's built-in converter (disabled by default, requires Java + Kotlin plugins)
ide_refactor_safe_delete	Safely delete an element, checking for usages first (Java/Kotlin only)

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

Project Lifecycle Management Tools

ide_project_status is enabled by default. All other lifecycle tools are disabled by default — enable them in Settings → Tools → Index MCP Server.

Tool	Description	Default
ide_project_status	Combined snapshot: every open project and every managed project with open/managed/mode per row	Enabled
ide_set_project_mode	Set a project's lifecycle mode: active, background, dormant, or closed	Disabled
ide_get_project_modes	List all managed projects and their current modes, including closed ones	Disabled
ide_set_all_project_modes	Set all managed projects to the same mode at once (active/background/dormant)	Disabled
ide_enroll_all_projects	Enroll every currently open project in lifecycle management	Disabled
ide_release_project	Unenroll a project from lifecycle management	Disabled
ide_release_all_projects	Release every managed project (including closed ones) from lifecycle management	Disabled
ide_lifecycle_log	Query recent lifecycle events from a ring buffer; each event has a trigger field explaining the cause	Disabled
ide_set_lifecycle_log_file	Enable or disable writing lifecycle events to mcp-lifecycle.log	Disabled

Lifecycle modes — transitions are automatic, driven by window focus and MCP activity:

Mode	Power Save	Editors	PSI Cache	Auto-transition
active	off	open	loaded	focus lost for N min → background
background	on	open	loaded	N min idle → dormant
dormant	on	closed	freed	N min idle → closed
closed	—	—	freed	next MCP call → background (auto-reopens)

Timing thresholds are configurable in Settings. Lifecycle management is opt-in (disabled by default); once "Enable lifecycle management" is turned on in Settings → Tools → Index MCP Server, projects enroll automatically on first MCP use and auto-reopen when an MCP tool targets a closed project — existing tools require no changes.

MCP availability guarantee: the lifecycle manager never closes below the configurable minimum of open managed projects (default 4) — projects at the floor stay in dormant (memory mostly freed, MCP still reachable) instead of closing. If all projects are somehow closed (e.g., the user manually closes the last window), any MCP tool call without a project_path automatically reopens a managed-closed project to restore access.

Tool Availability by IDE

Fully Tested:

IDE	Universal	Navigation	Refactoring
IntelliJ IDEA	✓ all universal tools	✓ 6 tools	✓ rename + move + reformat + optimize imports + safe delete + Java→Kotlin
Android Studio	✓ all universal tools	✓ 6 tools	✓ rename + move + reformat + optimize imports + safe delete + Java→Kotlin
PyCharm	✓ all universal tools	✓ 6 tools	✓ rename + move + reformat + optimize imports
WebStorm	✓ all universal tools	✓ 6 tools	✓ rename + move + reformat + optimize imports
GoLand	✓ all universal tools	✓ 4 tools	✓ rename + move + reformat + optimize imports
RustRover	✓ all universal tools	✓ 5 tools	✓ rename + move + reformat + optimize imports
PhpStorm	✓ all universal tools	✓ 6 tools	✓ rename + move + reformat + optimize imports

May Work (Untested):

IDE	Universal	Navigation	Refactoring
RubyMine	✓ all universal tools	✓ 2 Markdown tools	✓ rename + move + reformat + optimize imports
CLion	✓ all universal tools	✓ 2 Markdown tools	✓ rename + move + reformat + optimize imports
DataGrip	✓ all universal tools	✓ 2 Markdown tools	✓ rename + move + reformat + optimize imports

Note: Navigation tools activate when language plugins are present. Markdown adds heading search and file-structure support when the bundled Markdown plugin is enabled. Go and Rust do not expose ide_find_super_methods due to language semantics, and Go does not expose ide_find_implementations. Rename, move, reformat, and optimize-imports 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.

For Claude Code users: hooks that enforce IDE tool usage over bash/grep/sed fallbacks.

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 returns available_projects. By default this includes workspace sub-projects so AI agents can discover valid module content roots. If you want smaller error payloads, switch Project list in error responses to Compact in plugin settings to return only top-level project roots.

Lifecycle Management

When you use the plugin across multiple projects simultaneously — common when an AI agent is working across a monorepo — open projects compete for memory even when they're not being actively used. Lifecycle management handles this, but it is opt-in: enable "Enable lifecycle management" in Settings → Tools → Index MCP Server (disabled by default).

Once enabled, projects enroll on their first MCP tool call and are notified via balloon. From that point, transitions happen based on focus and MCP activity:

1. Focus lost → after 2 minutes, Power Save Mode on (background)
2. No MCP calls → after 2 more minutes, editors close and PSI cache is freed (dormant)
3. Still idle → after 10 minutes, project window closes entirely (closed)
4. Next MCP call → project reopens automatically, indexes, and responds normally

No changes are needed in existing MCP tools — ProjectResolver handles the reopen transparently. The auto-reopen typically takes 5–15 seconds on first open; subsequent opens are faster.

The lifecycle manager never closes below the configurable minimum of open managed projects (default 4): projects at the floor stay dormant (memory mostly freed, MCP still reachable) instead of closing. If all projects are closed by other means, any tool call automatically reopens one managed project to restore MCP access.

Use ide_project_status to see the current state of all projects at a glance, and ide_lifecycle_log to see what happened and why — useful when a project closed unexpectedly. Each log event has a trigger field: timer:inactivity, timer:close, focus_gained, mcp_call, auto_open, user, etc.

Timing thresholds are configurable in Settings → Tools → Index MCP Server → Project Lifecycle Management.

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

Action	Description
Refresh	Refresh server status and command history
Copy URL	Copy the MCP server URL to clipboard
Clear History	Clear the command history
Export History	Export history to JSON or CSV file
Install on Coding Agents	Install MCP server on AI assistants (prominent button on right)

Error Codes

JSON-RPC Standard Errors

Code	Name	Description
-32700	Parse Error	Failed to parse JSON-RPC request
-32600	Invalid Request	Invalid JSON-RPC request format
-32601	Method Not Found	Unknown method name
-32602	Invalid Params	Invalid or missing parameters
-32603	Internal Error	Unexpected internal error

Tool Errors

Since v5.0.0, tool-level failures (index not ready, file not found, symbol not found, refactoring conflicts) are returned as MCP tool results with isError: true and a descriptive message — not as custom JSON-RPC error codes. JSON-RPC error codes are reserved for transport-level protocol violations handled by the MCP SDK.

Settings

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

Setting	Default	Description
Server Port	IDE-specific	MCP server port (range: 1024-65535, auto-restart on change). See IDE-Specific Defaults
Server Host	127.0.0.1	Listening host. Change to 0.0.0.0 for remote/WSL access
Max History Size	100	Maximum number of commands to keep in history
Project List in Error Responses	Expanded	Controls available_projects detail for invalid/missing project_path errors. Expanded includes workspace sub-projects; Compact returns only top-level project roots
Sync External Changes	false	Sync external file changes before operations (WARNING: significant performance impact)
Response Format	JSON	Tool response serialization: JSON or TOON
Disabled Tools	Tool-specific	Per-tool enable/disable toggles. Disabled tools stay hidden and cannot be called until enabled
Lifecycle Management
Enable lifecycle management	false	Master toggle for the automatic sleep/wake state machine — no automatic sleep/wake happens until this is enabled
Active → Background (minutes)	2	Focus-loss grace period before switching to Power Save Mode
Background → Dormant (minutes)	2	MCP-idle time before closing editors and freeing PSI caches
Dormant → Closed (minutes)	10	Idle time before fully closing the project window
Minimum open projects	4	Floor of managed projects kept open (1-20); projects at the floor stay dormant instead of closing
Event log buffer size	500	How many events ide_lifecycle_log retains in memory (100–10,000)

Requirements

• JetBrains IDE 2025.3 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 or request)
                     ◄── JSON-RPC response or HTTP 202 Accepted
             ──────► POST /index-mcp/streamable-http (follow-up requests/notifications)
                     ◄── JSON-RPC response or HTTP 202 Accepted

The plugin uses stateless Streamable HTTP for the primary MCP transport. It does not issue Mcp-Session-Id headers, does not require session resumption, and does not implement or advertise authentication capabilities.

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 — everything, ~40s. Use -Ptier=unit for the fast headless tier only.
./gradlew test

# Run plugin verification
./gradlew verifyPlugin

See CONTRIBUTING.md for the test tiers and assertion rules.

License

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

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Plugin based on the IntelliJ Platform Plugin Template.