Use with ClaudeCookies
Cookie Policy
Last updated: 4 October 2026
1. In short
In the app, Lumin sets one cookie, to keep you signed in, and keeps three small values in your browser. On lumin.guru and docs.lumin.guru we ask once whether we may count your visit with Google Analytics, and one cookie remembers your answer. Google’s cookies are set only if you say yes. There are no advertising cookies anywhere.
2. The cookieApp
| Name | Set by | Purpose | Lasts |
|---|---|---|---|
| __Secure-better-auth.session_token | Lumin's sign-in service, for lumin.guru and its subdomains | Keeps you signed in to the app and lets an MCP client you connect finish signing in | 90 days, renewed while you use Lumin, removed when you sign out |
This cookie is strictly necessary. Without it you cannot sign in. It cannot be read by scripts on the page and is sent only over HTTPS.
Staff who open the admin panel also get a separate 12 hour cookie. Nobody else receives it.
3. Values kept in your browserApp
The app keeps these on your device. They are not cookies and are never sent to anyone else.
| Name | Where | Purpose | Lasts |
|---|---|---|---|
| lumin.visit | Session storage | A random id that groups the pages of one visit for our own app analytics (see the Privacy Policy, 2.9) | Until the tab closes, and replaced after 30 minutes idle |
| lumin:blur-titles | Session storage | Remembers whether you chose to blur conversation titles | Until the tab closes |
| lumin:sidebar-collapsed | Local storage | Remembers whether you collapsed the sidebar | Until you clear it |
4. lumin.guru and the docsLanding
We count visits two ways. Umami sets no cookie, stores nothing in your browser and keeps no identifier. It records the page, the referrer, the country, and the browser and device type.
We also use Google Analytics, but only with your yes. Until you answer, or if you say no, it runs in Google’s consent mode: it sets no cookie and stores nothing in your browser, and sends Google a page view without an identifier. Advertising features are off for everyone, always. One answer covers lumin.guru and docs.lumin.guru.
| Name | Set by | Purpose | Lasts |
|---|---|---|---|
| lumin_consent | lumin.guru, for lumin.guru and its subdomains | Remembers your Google Analytics answer, yes or no, so we do not ask again. Strictly necessary | 6 months |
| _ga | Google Analytics, only if you say yes | Tells your later visits apart from new visitors | 2 years |
| _ga_36SQ4J7YP8 | Google Analytics, only if you say yes | Keeps the state of your current visit | 2 years |
Saying no removes the Google Analytics cookies. Fonts are served from our own sites.
5. The MCP server and the pluginMCP
mcp.lumin.guru sets no cookies. Requests carry an API key or a sign-in token instead. The Lumin plugin for Claude Code keeps its settings, including the birth details you give it, in a file on your own computer.
6. Managing cookies
Your browser can show, delete or block cookies and site storage. Blocking the sign-in cookie for app.lumin.guru means you cannot sign in. Clearing site storage only resets the preferences above.
We do not track you across other sites, so Do Not Track and Global Privacy Control signals change nothing here.
7. Changes
If we ever add a cookie that is not strictly necessary, we will list it here first and ask for your consent where the law requires it.
Changes on 27 September 2026
The cookie is now listed by its production name, and every value the app keeps in your browser is listed by name. The admin cookie is disclosed, the page states that lumin.guru and the docs set no cookies, and the page covers the plugin.
8. Contact
Questions about cookies:
contact@lumin.guru