What this is, and what it is not.

Sonde is a reading of a public order book. It does not take your money, hold your money, place an order, or know who you are. These terms say that in full, in the plainest language we can manage.

Sonde is information, not advice. Every number here is arithmetic over prices Polymarket publishes. Nothing on this site is investment, financial, legal or tax advice, a recommendation to take any position, or an offer or solicitation to buy or sell anything. What you do with it is your decision and your risk.
Sonde is not an exchange, a broker or a bookmaker. You cannot deposit, trade, bet, or hold a balance here. There are no accounts. The site never touches a wallet, never asks for a signature, and has no write access to anything: it reads public data and shows it back to you.
The model can be wrong, and says so. The estimator is four published terms with a confidence floor, built from general research on market calibration rather than from a backtest of this board. It has no news and no knowledge of the world. A disagreement with the crowd is not a prediction, and confidence measures the evidence behind a quote, never the evidence behind reality.
Anything written by a language model is labelled as such. Where the analyst leg is switched on, its text is generated by a language model, on request, and may be confidently wrong. It is never an input to a price, a verdict or a ranking on this site.
We are not affiliated with Polymarket. Market data, prices, wallet positions and holder lists come from Polymarket's public API and belong to them. Sonde is not endorsed by, sponsored by, or connected to Polymarket in any way, and the accuracy, availability and continuation of that data are outside our control.
Trading on Polymarket has its own rules, and they are not ours. Access to Polymarket is governed by Polymarket's terms, which restrict who may use it — including, at the time of writing, persons in the United States and in other restricted jurisdictions. Reading a price on Sonde grants you no right to trade it. Whether you may legally participate in prediction markets or place a bet where you live is yours to establish before you act, as is meeting any age requirement that applies to you.
No warranty, and no liability for what you do with the numbers. The site is provided "as is" and "as available", without warranty of any kind. Upstream data can be delayed, stale, incomplete or simply wrong, and the site can be down. To the fullest extent the law allows, the operator of this site is not liable for any loss — trading losses first among them — arising from the use of, or the inability to use, this site.
Use it like a person, not like a scraper. Read the pages, call the API for your own use, build on it. Do not hammer it, resell access to it, strip its attribution, present its output as your own forecast, or use it to break Polymarket's terms or any law that applies to you. We may rate-limit or block traffic that damages the service for everyone else.
The code is MIT; the data is not ours to license. Sonde's own source is published under the MIT licence and you may use it accordingly. The market data it displays belongs to Polymarket and their users, and your use of it is subject to their terms.
These terms can change, and the site can end. When they change, the date at the top changes with them; continuing to use the site is how you accept the new version. We may modify, suspend or discontinue any part of the site at any time, including taking it down entirely.
Governing law. These terms are governed by the laws of Spain, and any dispute goes to the courts of Spain, without prejudice to any mandatory consumer protection you enjoy where you live.
Questions. Write to the contact address published in the site's repository. See also the privacy notice, which describes the data the site does and does not handle.