Installation

Platform Support

ArcKit CLI supports multiple installation methods across different platforms:

Platform	Claude Code Plugin	Gemini CLI Extension	Codex / OpenCode CLI
macOS	Full support	Full support	Full support
Linux	Full support	Full support	Full support
Windows (WSL2)	Full support	Full support	Full support
Windows (native)	Full support	Full support	Partial

Windows users: The Claude Code plugin and Gemini CLI extension work natively on all platforms. For Codex CLI / OpenCode CLI on native Windows (without WSL), some commands containing inline bash snippets may require Git Bash or WSL2. We recommend WSL2 for the best experience.

Installation Methods

Claude Code (Premier)
Gemini CLI
Codex CLI
OpenCode CLI

Claude Code provides the most complete ArcKit experience with all 54 commands, 5 autonomous research agents, 4 automation hooks, and bundled MCP servers.

Add ArcKit Plugin

Install the ArcKit plugin (requires Claude Code v2.1.63+):

/plugin marketplace add tractorjuice/arc-kit

Then install from the Discover tab.

Start Using ArcKit

Claude Code is ready to use immediately — no initialization needed. All commands, agents, hooks, and MCP servers are available.

/arckit.principles Create principles for a financial services company

Why v2.1.63? This version fixes memory leaks in subagents and long-running sessions (critical for ArcKit’s 5 research agents), resolves MCP server cache leaks on reconnect (affects all 4 bundled MCP servers), fixes stale skill caching after /clear, and adds worktree config sharing.

Why Claude Code?

Claude Code is the primary development platform for ArcKit and provides capabilities not available in other formats:

Feature	Claude Code	Gemini CLI	Codex / OpenCode
54 slash commands	✅	✅	✅
Templates & scripts	✅	✅	✅
Bundled MCP servers (AWS, Azure, GCP, DataCommons)	✅	✅ (3 servers)	Manual setup
Autonomous research agents (5 agents)	✅	—	—
SessionStart hook (auto-detect version + projects)	✅	—	—
UserPromptSubmit hook (project context injection)	✅	—	—
PreToolUse hook (ARC filename auto-correction)	✅	—	—
PermissionRequest hook (auto-allow MCP tools)	✅	—	—
Automatic marketplace updates	✅	✅	Manual reinstall
Zero-config installation	✅	✅	`arckit init` required

Gemini CLI provides a zero-config experience with all 54 commands, templates, scripts, and bundled MCP servers.

Install ArcKit Extension

gemini extensions install https://github.com/tractorjuice/arckit-gemini

Zero-config: all 54 commands, templates, scripts, and bundled MCP servers (AWS Knowledge, Microsoft Learn).

Start Using ArcKit

gemini

Use ArcKit commands immediately:

/arckit.principles Create principles for a financial services company
/arckit.requirements Build a payment processing system

Updating

Updates via:

gemini extensions update arckit

Codex CLI (OpenAI Codex CLI) requires manual installation and project initialization.

Install ArcKit CLI

pip install git+https://github.com/tractorjuice/arc-kit.git

Initialize Project

Create a new architecture governance project:

arckit init payment-modernization --ai codex

# Or initialize in current directory
arckit init . --ai codex

# Minimal install (skip docs and guides)
arckit init payment-modernization --ai codex --minimal

Set Up Environment

Set the CODEX_HOME environment variable:

# RECOMMENDED: Install direnv and allow
direnv allow

# Alternative: Export manually
export CODEX_HOME="$PWD/.codex"

Start Codex

cd payment-modernization
codex

Use ArcKit commands with /prompts: prefix:

/prompts:arckit.principles Create principles for financial services
/prompts:arckit.requirements Build a payment processing system

Upgrading

# Step 1: Upgrade the CLI tool
pip install --upgrade git+https://github.com/tractorjuice/arc-kit.git
# Or with uv:
uv tool upgrade arckit-cli --from git+https://github.com/tractorjuice/arc-kit.git

# Step 2: Update your existing project (re-run init in place)
cd /path/to/your-existing-project
arckit init --here --ai codex

This updates commands, templates, scripts, and agents while preserving your project data (projects/) and custom templates (.arckit/templates-custom/).

OpenCode CLI requires manual installation and project initialization.

Install ArcKit CLI

pip install git+https://github.com/tractorjuice/arc-kit.git

Initialize Project

Create a new architecture governance project:

arckit init payment-modernization --ai opencode

# Or initialize in current directory
arckit init . --ai opencode

Set Up Environment

Set the OPENCODE_HOME environment variable:

# RECOMMENDED: Install direnv and allow
direnv allow

# Alternative: Export manually
export OPENCODE_HOME="$PWD/.opencode"

Start OpenCode

cd payment-modernization
opencode

Use ArcKit commands:

/arckit.principles Create principles for financial services
/arckit.requirements Build a payment processing system

MCP Server Configuration

OpenCode projects include an .opencode/opencode.json file with MCP server configuration:

{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "aws-knowledge": {
      "type": "remote",
      "url": "https://knowledge-mcp.global.api.aws/sse",
      "enabled": true
    },
    "microsoft-learn": {
      "type": "remote",
      "url": "https://learn.microsoft.com/api/mcp/sse",
      "enabled": true
    },
    "google-developer-knowledge": {
      "type": "remote",
      "url": "https://developerknowledge.googleapis.com/mcp/sse",
      "headers": {
        "X-Goog-Api-Key": "${GOOGLE_API_KEY}"
      },
      "enabled": false
    }
  }
}

Google Developer Knowledge requires a GOOGLE_API_KEY environment variable to enable.

Requirements

ArcKit CLI requires:

Python: 3.11 or higher
Dependencies:
- typer — CLI framework
- rich — Terminal formatting
- httpx[socks] — HTTP client with SOCKS support
- platformdirs — Platform-specific directory paths
- readchar — Cross-platform keyboard input
- truststore>=0.10.4 — System certificate stores

All dependencies are installed automatically when you install ArcKit CLI.

Latest Release

Latest Release: v3.0.9

Next Steps

After installation, see the Quickstart guide to create your first ArcKit project.

Get Started

Core Concepts

Governance Workflow

Vendor Procurement

Design & Review

UK Government Compliance

Guides

Platform Support

Installation Methods

Why Claude Code?

Updating

Upgrading

MCP Server Configuration

Requirements

Latest Release

Next Steps

Build docs developers (and LLMs) love

Get Started

Core Concepts

Governance Workflow

Vendor Procurement

Design & Review

UK Government Compliance

Guides

​Platform Support

​Installation Methods

​Why Claude Code?

​Updating

​Upgrading

​MCP Server Configuration

​Requirements

​Latest Release

​Next Steps

Build docs developers (and LLMs) love

Platform Support

Installation Methods

Why Claude Code?

Updating

Upgrading

MCP Server Configuration

Requirements

Latest Release

Next Steps