jevarena
Spectator demo where two independent Jev agents play Snake side by side by clicking indexed direction buttons in separate iframe browsers.
Overview
JevArena is a public spectator demo by Raihan Khan in which two independent TypeSafe Jev agents play Snake in side-by-side browser panes using only clicks on indexed direction buttons. Each pane is a separate same-origin iframe with its own game loop, snake, food seed, buttons, score and crash state. The iframe streams a structured board snapshot to the parent page, which sends it to a server-only step route; Jev receives the head, body, food, score, current direction, tick, recent actions and only the legal, safe direction buttons as indexed targets, and the chosen target is clicked in that specific iframe.
There is no typing and no text model, only one server-side TypeSafe key, and live operation and direction probabilities are shown with an avatar flashing over the clicked control. The author explains choosing iframe browsing contexts over Playwright Chromium for the public deployment because persistent browsers and per-viewer streams would be heavier and less reliable, while keeping the browser-agent contract of live state, indexed targets and real clicks. It is a standalone Next.js image ready for Railway and MIT licensed.
What the decision model decides
| Type | Question | Answers |
|---|---|---|
| Choice | Which legal, safe direction button should be clicked next? | — |
How it works
- Each iframe streams a board snapshot
- Server asks Jev to choose among indexed safe direction buttons
- Selected button clicked in that iframe
- Probabilities and actions shown to spectators
Strengths
- Click-only, no text model
- Lightweight deployment without server-side browsers
- Visible per-step probabilities
Caveats
- Spectator demo, not an evaluation
- Only safe moves offered, which simplifies the task
At a glance
- Type
- Project
- Status
- prototype
- Language
- TypeScript
- Runtime
- Next.js
- Has code
- yes
- License
- MIT
Use cases and integrations
How curated lists describe it
Two Jev Agents play Snake in side-by-side browser panes with visible per-step choices.
logicrw/awesome-jev-projectsJevArena — two Jev agents duel in click-only browser games (Browser Use + TypeSafe Jev).
hellogumbo/awesome-jev
Frequently asked questions
How do the agents control the game?
By clicking indexed direction buttons in their own iframe browser.
Is a text model used?
No, it is click-only with one TypeSafe key.
Why not Playwright?
Persistent browsers per viewer were heavier and less reliable for a public demo.
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