Jev cannot write a single word. It only answers closed questions with calibrated probabilities, hundreds at a time, in about half a second. This world turns that into physics, chemistry, behaviour and direction.
Anything: obsidian, King Midas, Monday morning. There is no list of allowed materials.
16 questions about the thing (how it moves, colour, weight, surface, icon, temperature, runniness, blast size, what it keeps producing, gravity…) and 9 about every pair it forms with the world, both ways.
All questions go out at once, packed into ~9k-token requests. Latency barely depends on the count: 10 questions and 400 came back in the same ~0.5 s.
The engine knows 10 kinds of motion. Jev picks which one fits, who chases whom, who runs from whom. Its probabilities become reaction rates and branching ratios, sampled every frame.
Behaviour. For every pair Jev also answers "A notices B. Does A ignore it, chase it, run from it, or go towards it?" Zombies chase people (0.78), people flee zombies, mice flee cats (0.94), bees go to flowers (0.98), a dragon goes for gold (0.89). A "source" question decides what keeps coming out of something: a dragon's breath, a storm cloud's rain, a volcano's lava. A gravity question decides what pulls things in.
Looks. Jev picks each thing's surface (rocky, metallic, crystalline, molten…), its icon, how hot it is (heat haze, glow) and how runny (honey vs water). The renderer only knows how to draw those categories.
Direction. Dream a world asks ~400 questions about a sentence: does X belong here, where is it (ground, sea, sky, structure, falling…), which things are iconic, what the sky looks like. Jev plays god asks what to drop to reach a goal, then onto what.
Asked once ("a cell of A touches a cell of B, what does B turn into?"), Jev sees reactions that do not exist, and the worst ones are with the ground: a person standing on stone turns into stone. The same judgment asked four ways (two yes/no, two multiple-choice) drifts apart exactly when Jev is unsure, so the engine averages the four. On 92 hand-labelled pairs, three live runs each:
| false reactions | "standing on X turns you into X" | real ones found | right product | |
|---|---|---|---|---|
| one question | 6–7 / 52 | 4 | 40 / 40 | 39 / 40 |
| 8 questions per pair | 1–2 / 52 | 0 | 34–35 / 40 | all of them |
Thresholds were tuned on these same pairs, so this is a sanity check, not a held-out benchmark.
When the yes/no wordings say "no" but the multiple-choice ones say "yes, it becomes obsidian", the reaction is kept but made rare. Uncertain physics happens slowly, confident physics fast.
Lava on water: Jev splits its answer between steam and obsidian. The engine rolls the dice every time the two touch, so you get both, in Jev's proportions. The probabilities are the physics.
Row touches column. Colour = what the column material turns into (dark red = destroyed). Brightness = how fast. A small dot = the row creature chases (red), flees (blue) or goes towards (green) the column. Hover a cell for the raw answers.
Same material, same questions, same pairs. Who finishes first?