Preview: the CLI and API are not released yet.
Euthyne
CLI reference

euthyne login

Sign in from the terminal.

Coming soon

Planned command. Not released yet.
euthyne login

Signs you in with the OAuth device flow (RFC 8628). The CLI shows a code and a link. You confirm the code in your browser with your GitHub account.

The device token is stored in your OS keychain. It can only upload receipts for your own device.

init runs login for you when needed.