last-exit
Cyberpunk border-crossing game where Jev reads your cover story into observations and picks the inspector's next action.
Overview
Last Exit is a small browser encounter: something alive is in your cargo, and you must convince a border inspector there is not. You type your own cover story, hand over a manifest, or offer a bribe. Each player reply makes two Jev calls: one reads the player's statements into typed observations, and the other selects one of the inspector's available actions. The inspector sees the conversation, papers and evidence he has found but never the hidden cargo or scenario flag.
Dialogue lines are authored, scans and searches have deterministic consequences, and code prevents repeating a question and requires physical document or bribe controls, with a seven-turn limit. In a frozen batch of 100 scripted crossings (50 variants run twice), smugglers escaped 29 of 90 times and honest shipments passed 10 of 10, with 596 Jev requests, median local reply time of 537 ms and about $0.057 total input cost. The README stresses this is not a security or calibration benchmark and documents misreadings, such as treating an internal heater as a heat mismatch.
What the decision model decides
| Type | Question | Answers |
|---|---|---|
| Other | What typed observations does the player's statement contain? | — |
| Choice | Which available action should the inspector take next? | — |
How it works
- Player types a statement or uses document or bribe controls
- Jev extracts typed observations from the statement
- Jev chooses the inspector's next available action
- Code applies deterministic consequences and blocks repeated questions
- After at most seven turns, the inspector decides
Strengths
- Clear split between AI choice and game code
- Published evaluation with raw transcripts
- Very low cost per crossing
Caveats
- Scripted evaluation, not real players
- Known misreadings documented
- jev-latest alias may change outcomes
Getting started
npm ci && npm start, or play at gate.fade.tools.At a glance
- Type
- Project
- Status
- prototype
- Language
- JavaScript
- Runtime
- Node server and browser
- Has code
- yes
- Has tests
- yes
Use cases and integrations
How curated lists describe it
A cyberpunk border encounter powered by TypeSafe Jev. Bluff the guard. Inspect the receipts.
hellogumbo/awesome-jev
Frequently asked questions
What does Jev decide?
What the player's statement claims, as typed observations, and the inspector's next action.
Can I fool the guard?
In the scripted batch, smugglers escaped 29 of 90 times.
Does Jev write the dialogue?
No, dialogue lines are authored.
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