Frequently asked questions
This page answers broader questions about Ichnus and Curos: how the product is funded, what happens to your data, and how models are tested before release.
Is Ichnus really free?
Yes. Ichnus is free for individual use, including Corus, the largest model. Curos is a non-profit and does not charge for access. Heavy programmatic use through the API is offered as a program service at cost, which means you pay only what it costs Curos to serve it, with no markup. That revenue offsets infrastructure, but no one profits from it.
How is Curos funded?
Curos is funded by three sources:
- Foundations and government grants that support non-profit AI research.
- Individual donations from people who use and believe in the work.
- Program services, where organizations pay at cost for heavy API use.
Curos publishes a transparency report each year with its revenue, expenses, and governance decisions. The current report is linked from the footer of this documentation.
Is my data sold?
No. Curos does not sell, rent, or share your data with advertisers or data brokers. There are no ads in Ichnus and no advertising model to support. Your conversations are not used to train Curos models unless you opt in. For the full picture, including metadata and retention, see the Privacy page.
How are models tested?
Curos tests every model before release. Each model must pass release gates set by the Safety & Evaluations Committee:
- OversightQA, an eval that checks whether a model recognizes when it does not know the answer and whether it follows oversight correctly.
- Curos-Helpfulness, an eval that measures whether responses are actually useful across typical tasks.
- Red-team campaigns run by external researchers, focused on misuse and jailbreaks.
You can read the eval reports, including scores and failure cases, on the Safety and evaluation page. The reports are public and written to be readable by non-specialists.
Do I need to pay to use Corus?
No. Corus is free for individual use within fair-use limits. The limits exist to keep the service sustainable and to prevent one person’s workload from slowing the service for everyone. Limits reset weekly, and the current balance is shown on your account page. See Models and tiers for the current numbers.
What happens if I hit a fair-use limit?
For the rest of the weekly window, Corus requests are handled by Mantus instead, which continues to work normally. Nothing is deleted, and your balance resets on Monday. You can also purchase additional capacity at cost if you need it for research or programmatic work.
Is my conversation data used to train models?
Not unless you opt in. If you opt in, your conversations may be used to help evaluate and improve Curos models. Opting in is off by default, and you can turn it on or off at any time in Settings. You can also opt in retroactively for past conversations, or exclude specific conversations from use.
How is the Community Council chosen?
The Community Council is elected by Ichnus users. Council members serve staggered terms, meet with Curos staff regularly, and advise on features, model behavior, and policy. Elections are announced in the app and on the Community page, and any user in good standing can stand for election.
What is the difference between Curos, Ichnus, and the models?
Curos is the non-profit organization. Ichnus is the free assistant product built by Curos. Krus, Mantus, and Corus are the models that power Ichnus. Curos also publishes research and open evaluation tooling under its own name, separate from the Ichnus product.
Where can I ask questions not answered here?
The Community forum is the best place for questions other users can answer. For account or privacy questions, use the support contact form in the app, or email support using the address in the help menu.
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