Claude Code has broad access to a developer's machine, but existing authentication only verifies the Anthropic account for billing. The user requests local session authentication (PIN, TOTP, SMS OTP, passkey) to verify the current machine operator before accepting prompts.
### Observation Claude Code has broader access to a developer's machine than almost any other tool in routine use — shell execution, arbitrary file read/write, git history, environment variables, SSH keys, and credential stores. The existing authentication mechanism (OAuth / API key) authenticates the *Anthropic account* for billing purposes. It proves who owns the subscription; it does not verify who is operating the machine at a given moment. These credentials are stored persistently in OS credential stores and are available to any process that can invoke the `claude` binary. There is currently no mechanism to require the local user to re-authenticate before Claude Code accepts prompts in a new terminal session. --- ### Risk A bad actor who gains access to a running machine inherits Claude Code's full permissions automatically. No additional barrier exists. Specific scenarios: - **Physical access** — an unlocked workstation in an office, café, or shared space - **Lateral moveme