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Yeonsu is provided "as is" for informational purposes only. It is not a medical device and does not provide medical, dermatological, or professional cosmetic advice.
Ingredient analysis. Product ingredient data is sourced from the EU CosIng (Cosmetic Ingredient) database, retailer product pages, and publicly available INCI lists. While we cross-reference against over 30,000 EU-verified cosmetic ingredients, the data may be incomplete, outdated, or incorrectly extracted. Product formulations change over time, and the ingredient list shown may not match the exact version of the product currently available in your region.
Safety classifications. Ingredient safety ratings (safe, regulated, prohibited) are based on the EU Cosmetics Regulation (EC) No 1223/2009, including Annex II (prohibited substances), Annex III (restricted substances), and Annex IV (permitted colorants). These classifications reflect EU regulatory status and may differ from regulations in other jurisdictions. A "regulated" ingredient is legally permitted for use in cosmetics under specific conditions. Yeonsu does not assess whether a product complies with all applicable regulations.
AI-generated content. Product recommendations and ingredient descriptions are generated by AI language models. They are based on publicly available information and community discussions, and may contain inaccuracies, misinterpretations, or outdated information. Do not rely on Yeonsu as your sole source of information when making purchasing or health-related decisions.
Allergies and sensitivities. Yeonsu flags known common irritants and EU-mandatory allergens, but this is not an exhaustive assessment. Individual sensitivities vary. If you have known allergies or skin conditions, consult a dermatologist or allergist before using any product.
No affiliation. Yeonsu is not affiliated with, endorsed by, or sponsored by any brand, retailer, or regulatory body mentioned in search results. Product links are provided for convenience and do not constitute endorsements.
Limitation of liability. To the fullest extent permitted by law, Yeonsu and its creators accept no liability for any loss, damage, or adverse reaction arising from the use of this tool or reliance on its output.
What we collect. When you use Yeonsu, your search queries are sent to our server to generate results. Queries may be temporarily cached (up to 12 hours) to improve response times for similar searches. We do not create user accounts or profiles.
Session tokens. When you enter a beta invite code, a session token is stored in your browser (localStorage) and on our server (Cloudflare KV) for up to 7 days. This token is used solely to authenticate your access. It is not linked to any personal information.
Chat history. Your search history is stored locally in your browser using localStorage. It never leaves your device and is not sent to our servers. You can delete individual chats or clear all history at any time.
Waitlist. If you join the waitlist, your email address is stored in our database for the sole purpose of notifying you when Yeonsu becomes publicly available. We will not share your email with third parties or use it for any other purpose.
Third-party services. Yeonsu uses Brave Search to find product information and Anthropic's Claude to generate responses and extract data. Your search queries are sent to these services as part of normal operation. Please refer to their respective privacy policies for details on how they handle data.
No tracking. Yeonsu does not use cookies for tracking, does not run analytics scripts, and does not serve advertisements. We do not collect IP addresses, device information, or browsing behaviour beyond what is described above.
Data deletion. To delete your local chat history, use the delete buttons in the chat history sidebar or clear your browser's localStorage for yeonsu.co. To remove your email from the waitlist, contact us directly.