🧠 Leandix Cortex

IDE-native AI Coding Assistant

An AI-powered coding assistant that lives inside your editor — featuring Extended Thinking, multi-provider support, LSP-based context awareness, agentic tool calling, and full session undo.

Built from first principles: zero-latency startup · minimal footprint · true streaming

✨ Features

Feature	Description
🧠 Extended Thinking	Native support for Claude's thinking tags, rendered in a collapsible panel
🔌 Multi-Provider	Anthropic (native) + OpenAI-compatible (Gemini, Ollama, LM Studio, etc.)
🔗 LSP Context Graph	Symbol-level dependency traversal for precise, relevant code context
↩️ AI Action Stack	Full session undo — roll back all AI-initiated changes in one click
🤖 Agent Loop	Iterative tool calling: read, write, edit files, search codebase, run terminal
💬 Inline Chat	CodeLens-based interaction without leaving the editor
🔒 Tool Security	Mandatory user confirmation for destructive actions (write, edit, terminal)
📝 Aider Integration	Bridge to Aider for advanced multi-file editing workflows

🏗️ Architecture

┌──────────────────────────────────────────────────────┐
│                  PRESENTATION LAYER                  │
│  Inline Chat (CodeLens)   │ Sidebar (Svelte WebView) │
│                           │ + Tool Confirmation      │
└─────────────┬────────────────────────────────────────┘
              │ Events (postMessage) & Approvals
┌─────────────▼────────────────────────────────────────┐
│                  ORCHESTRATOR LAYER                  │
│  Event Bus   │   State Manager   │  AI Action Stack  │
└──────┬───────────────────────────┬───────────────────┘
       │                           │
┌──────▼──────┐      ┌─────────────▼───────────────────┐
│ LOCAL INTEL │      │            AI ENGINE            │
│ Classifier  │      │  Provider Abstraction (Factory) │
│ Token Count │      │  Stream Parser + Thinking Tags  │
│ 0ms Offline │      │  Agent Loop (iterative tools)   │
│             │      │  ➥ Pauses for Confirmation      │
└──────┬──────┘      └─────────────┬───────────────────┘
       │                           │
┌──────▼───────────────────────────▼───────────────────┐
│                CONTEXT & TOOLS LAYER                 │
│  LSP Context Graph │ Editor Manipulator │  Terminal  │
└──────────────────────────────────────────────────────┘

📁 Project Structure

leandix-cortex/
├── src/                        # Extension backend (TypeScript)
│   ├── extension.ts            # Extension entry point & activation
│   ├── core/                   # Core orchestration layer
│   │   ├── orchestrator.ts     # Main request orchestrator
│   │   ├── state-manager.ts    # Session & AI action stack state
│   │   ├── event-bus.ts        # Decoupled event system
│   │   ├── config-manager.ts   # Provider & workspace configuration
│   │   ├── thinking-parser.ts  # Claude thinking tag parser
│   │   ├── sse-buffer.ts       # Server-sent events buffer
│   │   └── types.ts            # Shared TypeScript interfaces
│   ├── engine/
│   │   └── agent-loop.ts       # Agentic tool-calling loop
│   ├── providers/              # AI provider abstraction
│   │   ├── factory.ts          # Provider factory
│   │   ├── anthropic-compat.ts # Anthropic API integration
│   │   └── openai-compat.ts    # OpenAI-compatible API integration
│   ├── context/
│   │   └── lsp-graph.ts        # LSP-based symbol dependency graph
│   ├── intelligence/
│   │   └── classifier.ts       # Local intent classifier (offline)
│   ├── tools/                  # IDE tool implementations
│   │   ├── ide-tools.ts        # File read/write/search/terminal tools
│   │   └── editor-manipulator.ts # Code diff & apply engine
│   ├── ui/
│   │   ├── sidebar/            # Sidebar webview provider
│   │   └── inline/             # Inline chat (CodeLens)
│   ├── aider/                  # Aider integration bridge
│   └── test/                   # Test suite (Mocha + Sinon)
│       └── suite/              # Unit tests for all modules
├── webview-ui/                 # Sidebar UI (Svelte + Vite)
│   └── src/
│       ├── App.svelte          # Root application component
│       ├── components/         # UI components
│       │   ├── Header.svelte
│       │   ├── MessageList.svelte
│       │   ├── MessageBubble.svelte
│       │   ├── InputArea.svelte
│       │   ├── MentionMenu.svelte
│       │   ├── HistoryPanel.svelte
│       │   ├── ToolConfirmCard.svelte
│       │   ├── StreamingIndicator.svelte
│       │   └── ClassificationBadge.svelte
│       ├── stores/             # Svelte stores (state management)
│       └── lib/                # Shared utilities
├── assets/                     # Static assets (icons)
├── build.js                    # esbuild bundler configuration
├── package.json                # Extension manifest & scripts
├── tsconfig.json               # TypeScript configuration
└── .vscodeignore               # Files excluded from VSIX package

🚀 Quick Start

Prerequisites

Node.js ≥ 18
VS Code ≥ 1.85.0
An API key from a supported provider

Installation from Source

# 1. Install dependencies
npm install
cd webview-ui
npm install
cd ..

# 2. Compile the extension
npm run compile

# 3. Package as VSIX
npm run package

# 4. Install in VS Code / Antigravity
code --install-extension leandix-cortex-0.1.0.vsix --force
antigravity --install-extension leandix-cortex-0.1.0.vsix --force

Provider Configuration

Create (or open) your config file at ~/.leandix/settings.json:

{
  "activeProfile": "default",
  "context": {
    "maxTokens": 80000
  },
  "agentLoop": {
    "maxIterations": 15
  },
  "providers": {
    "default": {
      "model": "claude-sonnet-4-5",
      "apiKey": "YOUR_ANTHROPIC_API_KEY",
      "baseURL": "https://api.anthropic.com",
      "smartModel": {
        "model": "claude-sonnet-4-5",
        "apiKey": "YOUR_ANTHROPIC_API_KEY",
        "baseURL": "https://api.anthropic.com"
      }
    }
  }
}

[!TIP] You can define multiple named profiles under providers and switch between them at runtime using Cortex: Switch Provider Profile.

⌨️ Keyboard Shortcuts

Shortcut	macOS	Action
`Ctrl+Shift+L`	`⌘+Shift+L`	Open Cortex Chat sidebar
`Ctrl+Shift+I`	`⌘+Shift+I`	Inline Chat (with current selection)
`Escape`	`Escape`	Cancel current streaming request
`Ctrl+Shift+Z`	`⌘+Shift+Z`	Undo last AI session

🔌 Provider Compatibility

Provider	Type	Extended Thinking	Tool Calling	Offline
Claude (Haiku / Sonnet / Opus)	`anthropic`	✅ Native	✅	❌
Gemini Flash / Pro	`openai-compat`	❌	✅	❌
Ollama (any model)	`openai-compat`	Model-dep	Model-dep	✅
LM Studio	`openai-compat`	Model-dep	Model-dep	✅

⚙️ Configuration

Project Rules

Create a .leandix/rules.md file in your workspace root to define project-specific instructions for the AI:

## Code Style
- Always use async/await
- Prefer explicit return types

## Constraints
- Never modify migration files
- Use English for all comments

Security & Tool Confirmation

All destructive operations (file writes, edits, terminal commands) require explicit user approval. Configure policies in your settings:

{
  "cortex.terminal.policy": "request-review",
  "cortex.terminal.allowList": ["npm", "git", "python"],
  "cortex.terminal.denyList": ["rm -rf", "DROP TABLE"]
}

🛠️ Development

Scripts

Command	Description
`npm run compile`	Build webview + compile TypeScript
`npm run watch`	Watch mode for extension backend
`npm run dev:webview`	Dev server for Svelte webview UI
`npm run build:webview`	Production build for webview UI
`npm run test`	Run unit tests (Mocha)
`npm run test:vscode`	Run VS Code integration tests
`npm run package`	Package extension as `.vsix`

Tech Stack

Extension Host: TypeScript, compiled with esbuild
Webview UI: Svelte + Vite
Testing: Mocha + Sinon
Packaging: @vscode/vsce

Running in Development

Open the project in VS Code
Run npm run watch in a terminal for backend hot-reload
Run npm run dev:webview in another terminal for webview hot-reload
Press F5 to launch the Extension Development Host

📄 License

This project is licensed under the MIT License.

Made with ❤️ by Leandix Engineering