Harmonograph is a browser extension for Chrome and Firefox that replaces your new tab page with a view of your Linear tasks, Google Calendar events, and world clocks. This policy explains what data the extension accesses and how it is handled.

DATA ACCESSED

Harmonograph requests read-only access to your Google Calendar data via the https://www.googleapis.com/auth/calendar.readonly scope. The following fields are fetched from the Google Calendar API:

• Event title (summary)
• Event start and end time
• Video conference link, if present
• Calendar names, used to let you select which calendars to show

Only events occurring on the current day are requested. No historical or future data beyond the current day is accessed.

DATA USAGE

Google Calendar data is fetched on each new tab load and displayed directly in the extension's UI. It is used solely to show you your meetings for the day. The data is held in memory only for the duration of the page session and is never written to disk, logged, or processed for any purpose other than display.

DATA SHARING

Google user data is never shared with any third party. Harmonograph has no backend servers — all API requests are made directly from your browser to Google's APIs. No calendar data is transmitted to, stored on, or processed by any server operated by Harmonograph or its developer.

DATA STORAGE AND PROTECTION

Harmonograph does not store your Google Calendar event data. How your OAuth credentials are handled depends on the browser, because the two provide different facilities:

• Chrome: the access token is managed entirely by Chrome's built-in identity system (chrome.identity) and is never accessed or stored by the extension directly.
• Firefox: Firefox provides no equivalent facility, so the extension manages the credentials itself. An access token and a refresh token are stored in local extension storage on your device. They are sent only to Google, and are deleted when you disconnect your calendar or uninstall the extension.

The settings data stored locally on your device is:

• Your selected calendar IDs (not event content)
• Theme preference and clock configuration
• Which Linear task statuses you have chosen to display
• Your Linear API key (if provided)

This settings data never leaves your device.

DATA RETENTION AND DELETION

No Google Calendar content is ever stored, and nothing is retained on any server — there are no servers. Everything Harmonograph keeps lives on your own device: your settings, and on Firefox your OAuth tokens. Disconnecting your calendar deletes the stored tokens, and uninstalling the extension removes everything.

To revoke Google Calendar access, visit https://myaccount.google.com/permissions and remove Harmonograph, or disconnect from within the extension's Settings panel.

THIRD-PARTY SERVICES

Harmonograph communicates directly with the following services on your behalf:

• Google Calendar API (https://policies.google.com/privacy) — to fetch today's calendar events
• Linear API (https://linear.app/legal/privacy) — to fetch your assigned issues (optional; requires a Personal API key you provide)

Your use of these services is governed by their respective privacy policies.

CONTACT
Questions about this policy can be directed to harmonograph@craftish.dev