Jev Dodge — an AI dodging falling rockets, live
Rockets fall down the grid and Jev, TypeSafe AI's decision model, has one tick to pick the safe column — left, stay or right — in a real API call. Watch its reflexes: the move it chose, its confidence, the latency and the cost, live above the board. No key, just press start.
The same demo is one Jev call
- Read the grid — your column, incoming rocket columns
- The choices are left / stay / right
- Send it to Jev as one
choicequestion - Jev returns the safe move (with confidence)
- Step, rockets fall, decide again next tick
const res = await fetch("https://jevtypesafeai.com/api/v1/decide", {
method: "POST",
headers: { Authorization: `Bearer ${process.env.JEV_API_KEY}` },
body: JSON.stringify({
state: `You are in column 3. Rockets falling in columns 3 and 5. Columns 2 and 4 clear.`, // the grid, as text
questions: {
move: { type: "choice", instructions: "Move to a safe column. Avoid the falling rockets.",
criteria: { left: "into column 2 — safe", stay: "column 3 — rocket incoming", right: "into column 4 — safe" } },
},
}),
});
const { answers } = await res.json();
step(answers.move.choice); // → "left" (0.79)See a real decision LEFT · 188ms
You are in column 3. Rockets falling in columns 3 and 5. Columns 2 and 4 are clear.
How Jev dodges the rockets
Rockets fall down a 7-column grid; Jev's block sits on the bottom row. Every tick, before the rockets drop one row, the whole grid is sent to the Jev API as a single request carrying one typed decision: a choice question named `move`, offering only the legal options — left, stay, right — that keep the block on the board. The state describes the grid as text: which columns hold rockets, which rockets are one row above the floor and about to land, and which columns are clear. Each option's criteria spells out the column it lands in and whether a rocket is about to drop onto it.
Jev returns the safe move with a calibrated probability, typically in 150–250ms, and the block slides that way just before the rockets fall. Because every tick is an ordinary API request, you see exactly what a developer wiring an LLM into real-time reflexes would see: the latency, the running cost — a fraction of a cent per decision — and the confidence behind the direction it just chose, live above the board. Survive longer and rockets start falling two at a time.
What is Jev?
Jev is TypeSafe AI's first System One model. Instead of writing prose like a chatbot, it reads a situation and returns a typed, calibrated decision — a choice between options, a score on a scale, or a yes/no probability — in tens to hundreds of milliseconds, with no hallucinations. Picking the one column that dodges an incoming rocket is exactly the kind of small, fast, bounded decision it is built for, which is why it can react tick after tick in real time.
The same model powers ticket routing, content moderation, lead scoring, agent tool-call guardrails and model routing in real products. Dodging rockets is just a visible, fun way to watch it decide — here it is deciding where to move to stay alive, and the confidence bar shows how sure it was about each dodge.
Reading the live decision
- The arrow and label show the move Jev just picked — LEFT, STAY or RIGHT — with its confidence as a bar and a 0–1 number.
- Latency is the round-trip time for that single decision; watch it stay in the low hundreds of milliseconds while the block reacts.
- The running cost adds up the input tokens of every tick at Jev's real price — a whole game costs a fraction of a cent.
- If a call errors or is rate-limited, the block falls back to a safe deterministic move (marked 'fallback') so it never freezes mid-game.
FAQ
Is Jev Dodge free to play?
Yes. It runs in your browser with no API key and no signup. You press start and watch — every tick is a free, rate-limited call to the live Jev decision API that picks the block's next move.
Does Jev really decide each dodge, or is it scripted?
Jev really decides. On every tick the grid is sent to the Jev API as one choice question over the legal moves (left / stay / right), and it returns the safe column with a calibrated probability. Only if a call errors or is rate-limited does the block fall back to a deterministic safe move, which the page marks as 'fallback'.
How fast and how expensive is each decision?
Each tick is a single API call that typically returns in about 150–250ms and costs a fraction of a cent in input tokens. The page shows the live latency, the running cost, and the confidence behind the move Jev just chose.
What am I looking at — real-time AI reflexes?
Yes. Rockets fall one row per tick and Jev must choose a safe column before they land, so you are watching an AI react under time pressure. Score is how many ticks it survives, plus how many rockets it grazes by one column — the near-misses.
More: Jev 2048 — watch the AI play · Jev Pac-Man — outrun the AI · Jev Trading Bot · All decision games · Jev API docs