# Yes / No

Last-Updated: 2026-09-17

> Yes / No (https://yesno.coderai.dev) is a free, no-sign-up demo of Jev, the System One model from TypeSafe AI (https://typesafe.ai). It answers any question with Yes, No, Maybe no, Maybe or Maybe yes. It is built by Coder AI (https://coderai.dev). When a question depends on current information, it checks a live Google web search before answering.

Tagline: "Less overthinking. More knowing." — One question, two possibilities (okay, maybe three).

## Jev and TypeSafe AI

- TypeSafe AI is an AI lab building machine-native intelligence infrastructure for automation, designed to make decisions within software.
- Jev is TypeSafe AI's first System One model, available in early access. Instead of writing prose, it returns how likely each answer is.
- Yes / No calls the `jev-latest` model through TypeSafe's System One API. It is the quickest way to test Jev for free: no account, no API key, no install.
- For API access to Jev, see https://typesafe.ai.

## How it works

- The user types a question of up to 1,000 characters and presses Ask (or Enter).
- Cloudflare Turnstile verification grants a signed, HttpOnly session for 30 minutes. Subsequent questions reuse it until expiry; rate limits still apply to every question.
- Jev estimates the probability that the answer is Yes. Below 45% the answer is **No**; 45% to below 50% is **Maybe no**; exactly 50% is **Maybe**; above 50% through 55% is **Maybe yes**; above 55% is **Yes**. Answers are never random; if the model fails, the page shows an error instead of guessing.
- In the same step Jev judges whether fresh web information would help. If so, the service runs one Google search and asks Jev again with the results as optional evidence.
- The page shows "Web search was used to refine this answer." when search was used, and "Could not ground results via web search." when search was needed but unavailable.

## Facts

- Price: free. No account or sign-up.
- Privacy: the application does not store or log questions. Questions are sent to the Jev model provider and, when search is needed, to the search provider.
- Limits: 100 questions per rolling hour, 1,000 per rolling day and 20 per minute burst per IPv4 address or IPv6 /64 subnet.
- Language: the interface is in English; questions can be asked in any language.
- Best for: quick decisions, sanity checks and simple factual or time-sensitive yes-or-no questions (for example "Will it rain in Kraków tomorrow?").
- Not for: medical, legal, financial or safety-critical decisions.

## Links

- App (free Jev demo): https://yesno.coderai.dev/
- Jev and TypeSafe AI: https://typesafe.ai
- Maker: https://coderai.dev/ (Coder AI)
- Coder AI products index: https://coderai.dev/llms.txt
- Sitemap: https://yesno.coderai.dev/sitemap.xml