datamodellib ("we", "us") is a free, open library of mental models. We designed it to work without accounts and to collect as little about you as possible. This policy explains what we do collect, why, and who else handles it.
The short version
- There are no accounts, sign-ups or passwords.
- We set no cookies and use no advertising or cross-site trackers.
- We never sell or rent personal data.
- The interactive labs run entirely in your browser; nothing you do in them is uploaded.
- If you use the AI mentor, your messages are sent to an AI provider to generate an answer.
What we collect
Server and security logs
Like every website, our hosting provider (Vercel) receives standard technical information when your browser requests a page or calls the API: your IP address, browser type, the page requested, the referring page and the time. These logs are used to deliver the site, keep it secure, prevent abuse and fix errors. They are kept by the hosting provider under its own retention policy and are not combined with other data to identify you.
Analytics
We use Cloudflare Web Analytics to count page views and see which pages are useful. It does not use cookies or local storage and does not track you across other websites. We see only aggregate figures such as page views, referrers, countries and device types.
Data stored in your browser
The guided tour saves a small flag in your browser's session storage so it can continue when you move to the next page. It contains no personal information and is deleted when you close the tab. We store nothing else in your browser.
The AI mentor
When the mentor is available and you use it:
- Your message, the earlier messages in that conversation and your settings are sent to an AI provider to generate the answer. We use, in order of preference, Groq, Mistral, Google (Gemini) and OpenAI, and the request may go to the next provider if one is unavailable.
- If web search is switched on, short search queries written by the AI may be sent to a search provider (Tavily or Brave Search), and public web pages from the results may be fetched.
- Your IP address is held briefly in memory to enforce rate limits. It is not written to a database.
- We do not store your conversations. The chat disappears when you leave or reload the page.
Each provider processes the data under its own terms and privacy policy, and some may keep it for a limited time for abuse monitoring. Do not enter personal, sensitive or confidential information in the mentor.
Messages you send us
If you open a GitHub issue or contact us, we receive whatever you choose to share, and GitHub's privacy policy applies to content posted there.
How we use information
We use the information above only to run, secure and improve the site and to answer questions you send us. We don't use it for advertising or profiling, and we don't make automated decisions about you.
Who we share it with
We share data only with the service providers that run parts of the site for us, as described above: our hosting provider, Cloudflare for analytics, and, when you use the mentor, the AI and search providers. We may also disclose information if the law requires it. We never sell personal data.
Links to other sites
The site links to other websites, including free learning resources and sites we feature, such as CreditBase. Their privacy practices are their own; please read their policies before sharing information with them.
Your rights
Depending on where you live, you may have the right to access, correct or delete personal data about you, to object to or restrict how it is processed, and to complain to a data protection authority. Because we don't run accounts or keep conversation histories, we usually hold nothing that we can link to you. To make a request or ask a question, open an issue on GitHub without including personal details, and we will arrange a private channel.
Children
The site is a general educational resource and is not directed at children under 13. We do not knowingly collect personal information from children.
Security
The site is served only over HTTPS, the API is read-only, and the mentor has rate limits and refuses to fetch private network addresses. No method of transmission over the internet is completely secure, but we keep what we collect to a minimum so there is little to expose.
Changes to this policy
If we change how the site handles data, we will update this page and the date at the top.