Playground
CommunityJev Demos & Experiments
Jev plays 2048
A live 2048 board on an independent Jev site. Each move is one Choice over the four directions, with a decision counter, latency, and a running cost.
- Format
- Playground
- Reading time
- 2 min
- Published by
- Community
- Last verified
- Sep 2026
Highlights
- Press play and every move is one Choice: up, down, left, or right. There is no separate policy model.
- The page quotes about 120 decisions a game, about 200 ms each, and well under one cent.
- The sample client posts the board and score to jevtypesafeai.com/api/v1/decide and plays answers.move.choice.
- The live panel shows decisions, last latency, Jev cost, score, and best tile.
Quickstart
ts
const res = await fetch("https://jevtypesafeai.com/api/v1/decide", {
method: "POST",
headers: { Authorization: `Bearer ${process.env.JEV_API_KEY}` },
body: JSON.stringify({
state: board,
questions: {
move: {
type: "choice",
instructions: "Best move for this board?",
criteria: { up: "slide up", down: "slide down", left: "slide left", right: "slide right" },
},
},
}),
});Watch out
Independent playground, not TypeSafe. The sample calls their /api/v1/decide proxy. The ~120-move and cost figures are the site's own estimates. Distinct from the ARCJ137442/jev-2048 repo.
Questions about this entry
Short answers drawn from the linked project or page.
Model-decided, per the page. Each move posts the board and score to the API as one choice over up, down, left, and right, and the client plays whatever comes back in answers.move.choice. There is no hard-coded 2048 strategy, and the page admits the model is not a dedicated solver.
It is the site's own arithmetic. It works from its rate of $0.042 per million input tokens and a few hundred input tokens per move, plus an estimate of about 120 decisions at roughly 200 ms each per game. Those are the site's figures, surfaced in the live counter panel, not an independent measurement.
Only the second. It is a general decision model choosing between four directions, so how far it gets varies from run to run and it will not always find the optimal move. Useful as a latency and cost demonstration, useless as evidence of search or planning ability.
It is independent and says it is not affiliated with or endorsed by TypeSafe AI. The sample client posts to jevtypesafeai.com/api/v1/decide, which is the site's own proxy rather than a vendor endpoint you hold a key for. It is also unrelated to the separate ARCJ137442 jev-2048 repository.
Decisions so far, the last latency, Jev cost, the current score and the best tile, so you can watch the per-move price and speed accumulate as the game runs.
The sample client posts the board and score as the state to jevtypesafeai.com/api/v1/decide with a bearer JEV_API_KEY, asking one Choice for the best move with up, down, left and right as criteria.
Yes. Each swipe is a real call to the decision endpoint and the board advances only after answers.move.choice returns; the page quotes about 120 decisions a game at roughly 200 ms each.
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