Install & Verify Command Sheet

Every command from the installation lectures, ready to copy. Use the part for your own operating system and ignore the rest.

Before you install, on any machine

node --version
npm --version

Write both numbers down. That is where you started, and you will want it later when you compare against the finished install.

macOS

Recommended install. Claude Code refreshes itself whenever a newer version is available.

curl -fsSL https://claude.ai/install.sh | bash

Alternative, if you already use Homebrew. It does not auto-update, so you upgrade by hand.

brew install --cask claude-code
brew upgrade claude-code

Verify:

claude --version
claude doctor

Then run claude once. Your browser opens and you sign in with your Anthropic account. You will not see that prompt again unless you log out.

If you hit permission errors, the usual cause is that ~/.local/bin is not on your PATH. See the PATH fixes below.

Windows with WSL2

In PowerShell opened as Administrator, once:

wsl --install

Then, inside Ubuntu, the install is identical to Linux:

curl -fsSL https://claude.ai/install.sh | bash

If claude --version comes back with command not found, the install worked and the terminal has not been told where to look:

echo 'export PATH="$HOME/.local/bin:$PATH"' >> ~/.bashrc && source ~/.bashrc

Then verify:

claude --version
claude doctor

Native Windows

Install Git for Windows first, from git-scm.com, with default settings. Claude Code uses Git Bash internally and the install fails without it.

Then in regular PowerShell, not Administrator:

irm https://claude.ai/install.ps1 | iex

Alternative through WinGet. It does not handle automatic updates, so you run winget upgrade periodically.

winget install Anthropic.ClaudeCode

If claude is not recognised, teach this window where to look:

$env:Path += ";$env:USERPROFILE\.local\bin"

Then verify:

claude --version
claude doctor

Linux

Same installer as macOS:

curl -fsSL https://claude.ai/install.sh | bash

PATH fix, on Bash:

export PATH="$HOME/.local/bin:$PATH"
source ~/.bashrc

On Z shell, the same export line goes into ~/.zshrc, then:

source ~/.zshrc

The five common errors and their fixes

Git not found, on Windows. Download Git for Windows from git-scm.com, install with default settings, restart your terminal, run the installation again.

Permission denied, on macOS or Linux. The native installer does not need sudo at all. Check whether ~/.local/bin exists and is on your PATH. If the folder is missing:

mkdir -p ~/.local/bin

Then re-run the installer.

Bash not found. Rare on standard systems. On a standard machine, reinstall with the native curl command. Inside a container, install Bash explicitly first.

Missing system libraries on Alpine Linux.

apk add libgcc libstdc++ ripgrep

Two C runtime libraries Alpine does not ship by default, plus ripgrep, the fast search tool Claude Code uses to find things across your project files.

npm and native conflict. If you installed the old way before:

npm uninstall -g @anthropic-ai/claude-code

Then install fresh with the native command for your platform.

For anything not on this list, paste the complete error message into Claude or another AI tool. A working solution comes back fast, because the error text is the thing that matters.

Your first session

claude

Then, at the end of it:

/usage

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