What this site does not collect
There is no account to make, no cookie to accept and no consent banner, because there is nothing to consent to. Everything below is enforced by the code rather than promised by this page.
Not collected at all
None of these exists anywhere in the system.
No accounts
Nothing to sign up for, so there is no name, no password and no profile.
No cookies
The site sets none. A session key and any lesson draft live in sessionStorage and die with the tab.
No third-party analytics
No external script runs on any page. Nothing is sent to another company.
No IP addresses
Not stored with any event, and not used to identify a reader.
Stored only in this tab
Stored by your browser, never sent to this service.
Lesson drafts
When you edit a minimal lesson, its title, objective, prompts, member choices and optional teacher note are kept in sessionStorage. The draft is scoped to that comparison, review date and member set, so it can be restored after you visit the evidence and come back.
The draft never leaves the browser, is unavailable to another tab, and is deleted when the tab closes or when you choose “Discard saved draft”.
What is recorded, and for how long
Two things are recorded, both deliberately shallow.
Product events
Which surfaces get used — a search happened, a comparison was opened, evidence was expanded. The route accepts only the ten names in an approved vocabulary and rejects any property outside a strict allow-list, so a search query cannot be recorded even by accident. Events carry a session key that exists only for the life of the browser tab.
Deleted after 90 days at the most, and the purge job refuses a longer window than that.
Issue reports
When someone reports a mistake, the report carries the record it is about, a reason, and whatever explanation they chose to write. It collects no identity — no name, no email, no address — and returns an anonymous reference, which is the only thread back to it.
The free text is redacted after the report is closed; the structured reason is kept, because that is what makes a pattern of complaints visible.
Why it is built this way
A product whose argument is that you can check its claims cannot ask you to take its data handling on trust. Collecting nothing is the only version of that promise which does not depend on us keeping it. It also costs something real: there is no way to email you when a comparison you read is corrected, and no way to recognise you between visits. That is the trade, made on purpose.
Report an issue is the one channel back to us, and it is anonymous by design.