Installation

Arnold installs into any AI coding agent. Pick the path that matches your tool. No API key, no database, no runtime dependencies.

Claude Code

Inside Claude Code, run:

/plugin marketplace add ArtifactHQ/arnold
/plugin install arnold@arnold-marketplace

Arnold's 17 slash commands (/arnold:init, /arnold:check, /arnold:plan, etc.) become available. Arnold's development rules load as a skill.

Commit your docs/ folder to Git so teammates see Arnold-generated documentation. The plugin itself is installed per-user and doesn't live in your repo.

Cursor, Codex, Antigravity, Windsurf, Gemini CLI

For every other agent, paste this one line into your agent's chat:

Install Arnold from ArtifactHQ/arnold — follow INSTALL.md

The — follow INSTALL.md suffix tells the agent to read INSTALL.md at the repo root, detect which tool it's running in, and perform the install to spec. Without it, some agents will improvise — always include the suffix.

In Cursor specifically, command names use hyphens (/arnold-init, /arnold-check, etc.) because Cursor doesn't allow colons in command names. Same content, different invocation.

Advanced variants

All of the following work by tweaking the same one-line install prompt. See the README install section for copy-pastable examples:

Pin to a version, or install from a branch or fork (e.g. ArtifactHQ/arnold@v0.5.0, acme-corp/arnold-fork@main)
Install from a local path or extracted release tarball (e.g. ./vendor/arnold/)
Install from an internal artifact registry for air-gapped or enterprise environments
Target a specific project directory with into /path/to/my-project
Codex: user-global plugin (default) vs. project-scoped skills vendored into one repo
scripts/install.sh flag-based fallback for CI pipelines and scripted deploys

Updating

Claude Code:

/plugin update

Cursor, Codex, Antigravity, Windsurf, Gemini CLI:

Update Arnold to the latest version — follow INSTALL.md

Or pin to a specific release: Update Arnold to v0.6.0 — follow INSTALL.md. Your agent re-runs the install procedure against the new version. For user-global Codex installs, restart Codex after the update completes.

Uninstalling

Claude Code:

/plugin uninstall arnold@arnold-marketplace

Cursor, Codex, Antigravity, Windsurf, Gemini CLI:

Uninstall Arnold from this project — follow INSTALL.md

For user-global Codex installs, use Uninstall Arnold — follow INSTALL.md instead.

Your docs/ folder is never touched on uninstall. Arnold-generated documentation is your content and survives the uninstall.

Next steps

Now that Arnold is installed, head to Your First 5 Minutes to set up your first project.