Can you beat Jev at Gomoku?

Every call to Jev

The exact request the server sent and the raw response. This is the whole of Jev: a list of options in, one choice with a probability for each option out.

No calls yet.
Jev's candidates
No move yet.
    What the marks mean
    • Green discs are Jev's five most likely moves, sized by probability. On wider screens the number on its last stone is how likely it thought that move was.
    • Thin rings mark the other candidates code offered.
    • "Via" says who decided: forced, only-move and longest-defence (no checked move holds; code blocks the biggest threat) were played by code without a call, best is Jev's own pick, and the heuristic rank is where that pick sat in the code's ordering.
    Moves
    #PlayedViaHeur.ConfmsTokens

    Sign in to play

    Games against the live Jev are recorded under your Google first name, and a win goes on the hall of fame. Only a hashed id and your first name are stored, never your email.
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    Your games
    Playing the live Jev needs a Google sign-in (top right, or at your first move). Your games and wins are kept under your first name, on any device.

    On this device

    Hall of fame
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    About

    Jev is TypeSafe AI's System One decision model. It does not generate text. You give it a state and a typed question with a list of options, and it returns one choice with a probability for every option. That is the whole interface, which is why a call costs a fraction of a cent and answers in a few hundred milliseconds.

    Why a board game. We first tried to play Go against large language models the usual way: describe the board in text, ask for a move. It was expensive, slow, and the models hallucinated: stones that were not there, illegal points, confident nonsense. Jev cannot hallucinate a move, because it can only pick from the options it is given, and every option here is legal by construction. Code computes the position (threats, captures, material); Jev judges among the candidates. The calls under the board show exactly what it saw and what it answered.

    What counts. A game against the live Jev is recorded move by move on the server, under your Google first name, so playing it asks you to sign in first. Beat it and your name goes on the hall of fame. Only a hashed id and your first name are stored, never your email.

    How Jev plays this game

    Source

    The whole site, engines included, is open: github.com/beingcognitive/jev-go. Chess pieces by Colin M.L. Burnett (CC BY-SA 3.0, from Wikimedia Commons, combined into one sprite); chess rules from chess.js.