Jev Use — shitianfang

The handoff is per step, not wholesale. dispatch.ts routes what never reaches Jev, and judge.ts screens, calls a backend, then hands back whatever is unsure with escalate: true and a typed reason. Your LLM still writes every word of output; Jev only answers typed questions about state your code builds. The Pong run made 86 decisions in 20 s against 6 for haiku and 3 for gemini called the usual way, and enum-constraining both narrows the gap to about 3x.

No. jev_gate is opt-in and can only deny or ask, never silently allow. Anything Jev cannot or should not decide returns escalate: true with a typed reason such as writing, open_ended, oversized, unsure or unreachable, and an unreachable backend escalates instead of allowing, so an unjudged command is never passed through.

Yes. JEV_BACKEND=mock runs a keyless dry run and stays local; every other backend sends judged state to whichever provider you configure. Otherwise set one key in the agent's environment: TYPESAFE_API_KEY, OPENROUTER_API_KEY, or AI_GATEWAY_API_KEY. npx -y jev-use doctor checks the wiring, and npm i jev-use also gives you a plain library with zero runtime dependencies on the judgment path.

The README points at bench/RESULTS.md for numbers, methodology, variance and caveats, and at docs/evidence.md for third-party measurements. Every demo is a rerunnable script in bench/examples, so you can regenerate them rather than take the claim. The compaction run judged 200 messages in 7 calls, filled the window to 94%, and passed 3/3 recall checks after it fell to 44%.

Run `npx -y jev-use install`, which wires Claude Code, Codex and pi, whichever it finds. Set one key in the environment your agent runs in (TYPESAFE_API_KEY, OPENROUTER_API_KEY or AI_GATEWAY_API_KEY), then check the wiring with `npx -y jev-use doctor`.

Yes, with `JEV_BACKEND=mock` for a keyless dry run. Judged state goes to the provider you configure while mock stays local. There is also a plugin form with the routing skill and the PreToolUse gate for Claude Code and Codex.

Anything Jev cannot or should not decide comes back with `escalate: true` and a typed reason, so the LLM takes over. The library's judge method takes check, pick and rate helpers, and answered choices carry an answer, a confidence and a confidenceFrom source.