Lightkone Your data
Lightkone has no accounts, no database of its own, no analytics and no ads. The site serves the app. Your library lives in storage you choose, and the app talks to it from your browser.
| What | Where it goes |
|---|---|
| Your papers, notes, highlights and PDFs | Only your own storage. The site never receives them, except when you use the AI app address (MCP): then the site's server reads your library from your storage for each request, with your storage keys sealed inside your private address. |
| Keys and tokens (Claude, GitHub, bucket, OpenAlex) | Only this browser's settings. Each is sent only to the service it belongs to. Invite links never carry them. |
| Ask, Explain, Summarize, Compare papers and Cite this's check | When you use them, your question and the passages picked from your papers (for a comparison table, each chosen paper's text; for Ask about five papers or fewer with Read the whole PDFs on, the PDFs themselves) go from your browser straight to Anthropic, with your own Claude key. |
| Your chats with Claude, and Claude's answers | Your own storage (lightkone/history/ for chats; lightkone/answers/, lightkone/citedby/ and lightkone/cite-draft.json for answers kept so they aren't asked for twice). In a shared or read-only library, this browser only. |
| Asking beyond your library | The words of your question go to OpenAlex's search. |
| Cite my draft | Your draft is read in your browser, and kept with your chats (above). A few words from each sentence you look up go to OpenAlex's search. With your Claude key, the uncited sentences (each with the one before it) and the passages found for them go straight to Anthropic. |
| How others cite this | The paper's DOI or arXiv id goes to Semantic Scholar. With your Claude key, the citing sentences and the paper's details go straight to Anthropic when you sort them. |
| Paper health | Your papers' DOIs go to Crossref, and their arXiv ids to arXiv through the site, about once a month. Nothing else about them is sent. |
| Journal citation styles | The style's name goes to the Citation Style Language project on GitHub, and the list of styles is fetched from Zotero. Your papers are formatted in your browser. |
| Adding and looking up papers | The DOI, arXiv id or title goes to Crossref, OpenAlex, Semantic Scholar or arXiv. For open-access PDFs, the DOI and your contact email go to Unpaywall through the site. A web page you add is fetched through the site, which passes only its address to the page's own server. If that server turns the site away, the address goes to Jina Reader (r.jina.ai) instead, unless you switch that off in Settings → DOI, arXiv and BibTeX. |
| Related papers and the citation map | The DOIs or arXiv ids of your papers go to OpenAlex or Semantic Scholar. |
| New on arXiv | Only the categories you follow go to arXiv, through the site. The ranking happens in your browser. |
| Search by equation | Each arXiv id goes to the site, which fetches that paper's public LaTeX source from arXiv and returns its equations. |
The site's few server functions exist only where browsers aren't allowed to call a service directly (arXiv listings and sources, open-access PDFs, published versions, and the MCP address). They keep nothing; public answers from arXiv are cached for a while. The host (Cloudflare) keeps its usual request logs.
The same table is in the app, under Help → Your data.