OpenSpec Install Skill

Install the OpenSpec CLI so that openspec is available globally. This skill covers only installing the CLI; it does not run openspec init. For project initialization after install, use openspec-initial.

When to Use

• First-time OpenSpec setup ("install OpenSpec", "get started with OpenSpec").
• User reports "openspec: command not found".
• Upgrading to the latest version.
• CI or scripts that need the CLI pre-installed.

Prerequisites

• Node.js 20.19.0 or higher — Check with node --version. If not installed, guide the user to install Node.js first (e.g. via nvm, fnm, or official installer).

Workflow

1. Check if already installed

   • Run openspec --version. If it succeeds, the CLI is already installed; suggest openspec-initial for project setup or upgrading via npm install -g @fission-ai/openspec@latest.

2. Choose package manager and install

   • npm (most common): npm install -g @fission-ai/openspec@latest
   • pnpm: pnpm add -g @fission-ai/openspec@latest
   • yarn: yarn global add @fission-ai/openspec@latest
   • bun: bun add -g @fission-ai/openspec@latest
   • nix (one-time, no install): nix run github:Fission-AI/OpenSpec -- init
   • nix (persistent): nix profile install github:Fission-AI/OpenSpec

3. Verify installation

   • Run openspec --version to confirm.

4. Upgrade existing installation

   • Same command as install — e.g. npm install -g @fission-ai/openspec@latest.

Outputs

• openspec command available globally in PATH.

Next Steps

• Use openspec-initial to run openspec init in a project.
• Or use openspec-onboard for a guided tutorial.

Different Environments

Environment	Command
npm	npm install -g @fission-ai/openspec@latest
pnpm	pnpm add -g @fission-ai/openspec@latest
yarn	yarn global add @fission-ai/openspec@latest
bun	bun add -g @fission-ai/openspec@latest
nix (one-time)	nix run github:Fission-AI/OpenSpec -- init
nix (persistent)	nix profile install github:Fission-AI/OpenSpec
CI	npm install -g @fission-ai/openspec@latest in a cacheable step

Troubleshooting

• Node.js version too old: OpenSpec requires Node.js 20.19.0+. Upgrade Node.js first.
• Permission errors (npm): Use npm install -g without sudo if using nvm/fnm; otherwise consider using nvm.
• Command not found after install: Ensure the global bin directory is in PATH (check npm bin -g).
• nix not available: Install nix or use npm/pnpm/yarn/bun instead.

References

• OpenSpec Installation docs
• OpenSpec GitHub