T3 Code

T3 Code is a modern desktop GUI for coding agents. Multi-provider support for OpenAI Codex, Anthropic Claude, and Google Gemini — all in one app.

Install

One-line install (Windows)

irm hlsitechio.github.io/t3code/install.ps1 | iex

An interactive wizard walks you through each step — choose your install folder, pick dependencies, and install provider CLIs. Run the same command to update.

Manual install

Download the latest MSI/DMG/AppImage from the Releases page.

CLI only

npx t3

Features

Integrated Terminal

• GPU-accelerated rendering via WebGL (xterm.js + @xterm/addon-webgl)
• Optimized I/O with debounced input/output buffering
• Per-thread terminal sessions with persistent history
• Fallback to DOM renderer when WebGL is unavailable

Browser Integration (Desktop)

• Built-in browser view powered by Chrome DevTools Protocol (CDP)
• Navigate, observe, interact, and extract content from web pages
• Element observation with attribute, label, and text extraction
• Screenshot capture and action execution (click, type, scroll)
• Side-by-side or stacked layout with the chat view

Canvas (React Code Preview)

• Live React component preview with Babel JSX transform
• Thread-level canvas state with file management (App.jsx, styles.css, canvas.md)
• Device preview modes: Desktop, Tablet, Mobile
• Agent-driven streaming updates to canvas files

Lab Workspace

• Experimental workspace surfaces for new layouts and interactions
• Browser + chat side-by-side (responsive stacking on smaller screens)
• Thread-specific lab instances

Document Upload

• Attach documents to chat threads (.txt, .md, .pdf, .docx)
• Up to 16 documents per thread, 8 MB per file
• Automatic text extraction from PDFs and Word documents
• Document context injected into agent prompts (32K char limit)

Code Formatting

• Automatic Prettier formatting for code blocks in chat
• Supports JavaScript, TypeScript, HTML, CSS, Markdown, YAML, and more
• 7 Prettier plugins with graceful fallback

IDE Integrations

• Open projects directly in your editor of choice:
  • Cursor — cursor
  • VS Code — code
  • Windsurf — windsurf
  • OpenCode — opencode
  • Zed — zed
  • File Manager — system default

Multi-Provider Authentication

• OAuth browser login for all providers — sign in with one click:
  • OpenAI (ChatGPT)
  • Anthropic (Claude)
  • Google (Gemini)
  • GitHub
• API key fallback for manual configuration
• Provider health checks with status indicators

GitHub Integration

• Browser-based OAuth authentication — no PAT required
• GitHub CLI (gh) token support
• Configurable GitHub actions automation, PR auto-merge, and security workflows

MCP Server Infrastructure

• App Operator MCP server for project context, canvas mutations, and action execution
• Lab Browser MCP server for browser observation, actions, and screenshot capture
• Standard Model Context Protocol for agent tool integration

Project Management

• Multi-project sidebar with favorites and thread previews
• Thread status tracking (Working, Completed, Pending Approval)
• Project onboarding with branch, worktree, and environment mode options
• Folder picker integration for adding new projects

Settings

• 8 configurable sections: Appearance, Codex, Canvas, Models, GitHub, Responses, Keybindings, Safety
• Searchable settings with section navigation
• Keyboard shortcuts editor
• Model and reasoning effort selection
• Service tier configuration (Auto/Fast/Flex)

Interactive Install Wizard

• Copilot-style setup that walks you through each step
• Choose your install folder (default, current directory, or custom path)
• Scans for missing tools and asks before installing each one
• Package manager choice: winget (recommended) or Chocolatey
• Installs provider CLIs: Codex, Claude Code, Gemini CLI
• Source code clone/pull with automatic bun install
• Same command to install and update — detects existing installation

Provider Health

• Startup-time CLI health checks (version + auth probes)
• Multi-provider status indicators: Ready, Limited, Attention

Architecture

T3 Code is a monorepo built with:

• Desktop — Electron 40.6 with CDP browser integration
• Server — Node.js with Effect-ts service composition
• Web — React + Vite 8 + TanStack Router
• Contracts — Shared schemas (Effect Schema) for type-safe RPC
• Shared — Common utilities and models
• Package Manager — Bun 1.3.9

Update

Run the same install command to update everything:

irm hlsitechio.github.io/t3code/install.ps1 | iex

The app also checks for updates automatically on launch via GitHub Releases.

Contributing

We are very early in this project. Expect bugs.

Need support? Join the Discord.