Any yes-or-no question
Type the question, shake the ball and read the verdict — the interaction is deliberately kept to a single gesture.
AI web app · JEV & Tavily
YesNoBall
A playful online crystal ball: ask a yes-or-no question and the JEV AI model answers. Behind the toy sits a real experiment — grounding a language model with live web search so even factual questions get an honest answer.
/01 The problem
The magic 8-ball has answered yes-or-no questions with a random shake for decades. The obvious question was what happens when the randomness is replaced by a language model — and where that stops being fun and starts being wrong.
Because the honest failure mode of a talking oracle is confidence without knowledge. A model will happily answer "yes" to a question about a real event it knows nothing about. So YesNoBall pairs the model with live fact verification: when a question is checkable, the answer is grounded in sources retrieved through the Tavily API rather than in the model's memory alone.
/02 What it does
ASK
AI
FACTS
FREE
Answers from the JEV model
The JEV model produces the verdict and a short reasoning, so the answer is more than a coin flip.
Verification through Tavily
Factual questions are checked against live web results through the Tavily API before the ball commits to an answer.
Free, with a tip jar
The site is free to use; anyone who enjoys it can "light a candle" — a small tip through Ko-fi.
/03 How it works
/01
The question
The visitor asks the crystal ball in the browser; no account, no setup, no form beyond the question itself.
/02
The backend
A PHP backend receives the question, decides how it should be handled and keeps the API keys away from the browser.
/03
Model and sources
The JEV model forms the verdict; for checkable questions the Tavily API retrieves current sources so the answer is grounded in something real.
/04
The verdict
The ball delivers a yes or a no with a short explanation — the whole point is that the answer arrives in one breath.
/04 Under the hood
BACKEND
AI
SEARCH
SUPPORT
PHP
A small, boring backend that orchestrates the calls and keeps credentials server-side.
JEV model
The language model behind every verdict, integrated through its API.
Tavily API
Live web retrieval used to verify claims before the ball answers a factual question.
Ko-fi
Optional tips through Ko-fi keep the lights on; there is no paywall and no advertising.
2026Launched 21 September
0 €Free to use
2APIs: JEV and Tavily
1Question at a time
/05 FAQ
Is YesNoBall serious?
It is a toy with a serious core. The experience is playful, but the answer comes from a language model whose factual claims are verified against live web sources — which is exactly the pattern serious AI products need.
Which AI model answers the questions?
The JEV model, integrated through its API and called from a PHP backend.
How does the fact-checking work?
When a question can be checked against the real world, the backend retrieves current sources through the Tavily API and the answer is grounded in them rather than in the model's memory alone.
Does it cost anything?
No. The site is free; if you enjoy it you can leave a small tip through Ko-fi, but nothing is locked behind it.
Should I make decisions based on the answer?
Please do not. Treat it as entertainment and as a demonstration of how a model plus live retrieval behaves — not as advice.