Question 1

Does it fall back to search when Jev is unsure, or is that the point?

Accepted Answer

Not falling back is the point. There is no heuristic algorithm anywhere in the project: when the model is uncertain, the uncertainty is exposed to the user instead of being replaced by something that plays better. Latency, upstream call count and cost are first-class outputs of the request rather than statistics added afterwards, and the probability distribution, confidence and token use are all surfaced in the interface.

Question 2

What does the broker actually buy me?

Accepted Answer

It wraps any OpenAI- or Anthropic-compatible LLM in the Jev request and response shape, so the decision and evaluation code above it is unchanged and cannot tell which backend answered. That lets the same board be played by Jev and by a wrapped chat model, and makes the cost of a per-cell parallel decision comparable against the round trips a chat model would need.

Question 3

Can I run it without a TypeSafe key?

Accepted Answer

Yes, for a dry run: tools/play.ts with --dry-run drives the same pipeline as the interface using fixed-seed fake probabilities and spends nothing. The deployed demos also work without a key on shared free trial endpoints, but those are public, unauthenticated and quota-limited, and sustained or batch use is meant to move to your own key, read from the environment, a sealed file or a plaintext file outside the repo.

Question 4

Are the sealed key files outside the repo actually secret?

Accepted Answer

No, and the README says so. The default passphrase is in src/server/seal.ts, so anyone with the repository can decrypt them; it protects against a key being catted, screenshotted or committed by accident, not against anyone targeting it. Setting JEV_SEAL_PASSPHRASE leaves only a useless default in the source. The real boundary is that keys never reach the client and live in server environment variables.

Question 5

What stack do I need, and what does startup check?

Accepted Answer

Node.js 22 or newer, and TypeScript throughout with no bundler, because the browser loads tsc's ES modules directly. ./start.sh runs seven steps and aborts on the first failure: a secret scan, a layering check that core/ never imports client/, a DOM id consistency check, 461 unit tests, the client build, the server build, and serving on port 8787.

Question 6

Why is Jev the first player rather than a helper?

Accepted Answer

Because the Chess of Life has no opening theory and no human strong play to imitate, so a freshly written ruleset is missing exactly one thing: someone actually walking it once. Jev starts from the rules themselves, and how the rules are phrased to it is editable, so whether a ruleset is playable and whether it was explained clearly both become visible within a single game.

Question 7

What is licensed here, and how does the two-player mode work?

Accepted Answer

MIT. Conway's Life rules are public domain and only borrowed as a decision scenario, while the Chess of Life ruleset itself belongs to the repo. The two-player mode is deliberately asymmetric, one side flipping dead cells alive and the other live cells dead, so their legal sets are naturally mutually exclusive and can never collide on the same cell, which removes any need for conflict resolution.

Jev Life

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