TECH.IDX RnD/technical/2026-07-25-rules-engine-authoritative-rng/prototype/README.md raw.md ->

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 provides loadFixtureBundle();
../../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:

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

Run from the study directory:

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.

Run the root compiler separately:

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.