# Prototype: Rules and Authoritative RNG Verification

This directory contains six executable contract tests against the shared AI-GM
vertical-slice engine. It does not contain a duplicate rules engine, event log,
state model or rules profile.

Authoritative dependencies:

- [`../../2026-07-25-ai-gm-vertical-slice/prototype/src/fixtures.ts`](../../2026-07-25-ai-gm-vertical-slice/prototype/src/fixtures.ts)
  provides `loadFixtureBundle()`;
- [`../../2026-07-25-ai-gm-vertical-slice/prototype/fixtures/game-contract.json`](../../2026-07-25-ai-gm-vertical-slice/prototype/fixtures/game-contract.json)
  is the single attributed/original Game Contract and rules-profile fixture;
- shared `contracts`, `engine`, `event-log`, `hash` and `state` modules are
  imported directly by `rules-engine.verification.test.ts`.

The former local `original-genre-neutral-profile.ts` duplicate was deleted so
the shared fixture remains authoritative.

Run from the repository root on Node.js `v24.14.0`:

```bash
node --test RnD/technical/2026-07-25-rules-engine-authoritative-rng/prototype/rules-engine.verification.test.ts
```

Run from the study directory:

```bash
node --test prototype/rules-engine.verification.test.ts
```

The recorded result is `6` tests, `6` pass, `0` fail, `0` skipped and `0` TODO:

- AC-01 checks complete roll calculation plus stored event reference for both
  registered roll-producing command kinds;
- AC-02 rejects fabricated client/LLM roll fields and accepts only server RNG;
- AC-03 stops every labelled invalid command before RNG/event/state work;
- AC-04 returns the original event for a duplicate without a second effect;
- AC-05 rejects a stale expected state version before mutation;
- AC-06 verifies the shared versioned profile’s official attribution and
  original genre-neutral executable fields.

Official primary source for the recorded inspiration/license evidence:
[Questing Beast — Knave](https://questingbeast.itch.io/knave).

Run the root compiler separately:

```bash
npm run typecheck
```

The final compiler run exits successfully. The first behavior run exposed a
non-erasable TypeScript constructor parameter property; the test now uses an
ordinary field plus constructor assignment and runs under Node’s built-in strip
mode without an experimental flag. No network service, environment variable or
study-local dependency install is required.