The art manifest referenced /art/*.png files that never existed; the SPA fallback returned index.html for them, so the library thumbnails rendered as broken images. Generate 5 atmospheric B&W placeholder scenes (tools/gen-art-placeholders.mjs, npm run gen:art) into public/art/. tests/tools/art-assets.test.js ties every manifest entry to a real PNG. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The Director
An offline-first tablet app for running tabletop RPG sessions at conventions.
Its permanent feature is the Director Rail — an always-on pacing co-pilot that keeps a hard-clocked slot on time — sitting above a pluggable shell that hosts any game system and any scenario. Built for face-to-face play: no server, no wifi, no install ceremony. Open it on the tablet and it works.
Working name "The Director". Repo
gmtool. First deployment: Continuum 2026 — but built as a reusable product for any convention, not one con's materials.
Status
Slice 1 — complete. Proven end-to-end against the AFTERIMAGE pilot scenario:
<gm-shell>— root: owns the session clock, scenario, beat stamps, and persistence.- Director Rail — session clock, "you are here" vs target with a live drift badge, next hard trigger countdown, and one-tap "Reached it" stamping (no mental arithmetic mid-scene).
- Dice engine — one seedable core (any die: d4–d100, dF, pools, modifiers) plus pluggable system rule-packs that interpret a roll. Ships with Year-Zero (6–9 = success, 10+ = two).
- Scenario data model — one structured file per scenario; the source of truth (see below).
- Persistence — namespaced
localStoragewith JSON export/import for backup and device swap. - Installable PWA — a service worker precaches the shell so it launches offline.
Deferred to later slices: NPC generator, art generator, the rest of the tray tools, more rule-packs and scenarios, and the clue safety-net. See the roadmap below.
Quick start
npm install
npm run dev # local dev server
npm test # Vitest suite (jsdom)
npm run build # static production build → dist/
npm run preview # serve the production build
Requires Node ≥ 18. No runtime framework — the only dependencies are dev tools (Vite, Vitest, jsdom).
Architecture
Vanilla ES modules and Web Components (light DOM) over a thin core of pure, deterministic
logic. All testable logic lives in src/core and src/dice and takes an injected now (ms) or
rng (() => [0,1)) — no Date.now() / Math.random() inside — so tests are fully deterministic.
Components are dumb renderers that emit events; the shell wires them together.
| Unit | Responsibility |
|---|---|
src/core/store.js |
Namespaced localStorage (gmd.<namespace>.<key>) + export/import |
src/core/clock.js |
Pure session clock: start / pause / resume / elapsed |
src/core/timeline.js |
Drift + next-hard-trigger analysis from the scenario timeline |
src/core/scenario.js |
Scenario validator |
src/core/format.js |
Elapsed + drift display formatting |
src/dice/roller.js |
Seedable dice core (pools, modifiers) |
src/dice/rulepacks/ |
System interpreters (Year-Zero, CoC d100, BRP d100, VANITY d6, Panic & Glory, Dee Sanction) + registry |
src/npc/ |
NPC generator (generator.js) + genre table packs (packs/noir.js) |
src/art/ |
Pencil-art library search (search.js) + tagged manifest; online generate.js (configurable endpoint) + library.js (persisted, capped generated-art cache) |
src/clues/safety-net.js |
Clue safety-net engine (essential-gap + solvability) |
src/con/schedule.js |
Pure convention-schedule analysis (live / up-next / done / upcoming) |
src/components/con-hub.js |
<con-hub> — the convention landing screen; deep-links into a scenario |
src/scenarios/index.js |
Scenario registry (getScenario(id)) the hub deep-links through |
src/con/ |
Convention data (continuum-2026.js; example-con.js is a fully-timed template) |
src/components/director-rail.js |
<director-rail> — the always-on pacing bar (🏠 🎲 👤 ✏️ 🔍 👥 ☕ chips; ☕ shows an on-break badge) |
src/components/dice-tray.js |
<dice-tray> — pack selector + die picker + roll + verdict |
src/components/npc-tray.js · art-tray.js · prop-viewer.js · clue-net.js · cast-tray.js · break-timer.js · parking-lot.js |
The tray tools (cast-tray = roster w/ tap-to-reveal secrets; break-timer pauses the clock so breaks never poison drift; parking-lot = timestamped thread capture) |
src/core/wake-lock.js |
Screen Wake Lock controller (keep the tablet awake; re-acquires on foreground; graceful no-op where unsupported) |
src/components/gm-shell.js |
<gm-shell> — root wiring + persistence |
src/scenarios/ |
Scenario data files (six Continuum slots: afterimage, day-one, vain-crown, silvery-moon, chopper, princes-bride; example-with-clues.js is a template); index.js is the registry |
public/ |
manifest.webmanifest, sw.js (offline service worker) |
Scenario data model
A scenario is one JS module — the single source of truth the Rail reads. The timeline is authored in relative minutes from Start (con slots begin late; relative timing keeps drift honest).
export default {
meta: { id: 'afterimage', title: 'AFTERIMAGE', system: 'year-zero', players: 4, playMinutes: 210, slot: 'Fri · Slot 2' },
timeline: [
// targetMin = minutes after the GM taps Start
{ id: 'a1-open', label: 'The pier — the case lands', targetMin: 0, hardTrigger: true },
{ id: 'a1-parlor', label: 'Parlor 88 interview', targetMin: 35, cutHint: 'Summarise the ledger; skip the tea ritual' },
{ id: 'a2-doorcam', label: 'Door-cam reveal', targetMin: 120, hardTrigger: true },
// …
],
clues: [], cast: [], props: [], // reserved for later slices
}
meta.system selects the dice rule-pack. hardTrigger marks immovable beats; cutHint is what to
compress if you reach a beat behind schedule.
Generating a scenario from markdown
Instead of hand-writing the module, author a scenario in a structured markdown file and generate it:
npm run gen:scenario -- input.md src/scenarios/my-scenario.js # or omit the output path to print
The tool (tools/scenario-md.js, wrapped by tools/md-to-scenario.mjs) is a deterministic parser —
frontmatter → meta, and ## Timeline / ## Clues / ## Cast lists → the arrays. See
tools/example-scenario.md for the full format; in short:
---
id: my-scenario
system: year-zero
players: 4
playMinutes: 210
---
## Timeline
- [0] The opening beat {hard} #a1-open ← [minutes] label, {hard}, optional #id
- [35] Interview | cut: skip the tea ritual ← | cut: … → cutHint
## Clues
- The door-cam face {essential} {act: Act One} | fallback: the monologue cards
## Cast
- MARY FLETCHER — Innkeeper; saw the watchers | secret: she saw Crowe sew
IDs are auto-slugged from the label/name when not pinned with #id. The output is validated against
validateScenario before it is written. It emits app data only, not prose — freeform con docs are
not parsed; you write the structured markdown. The tools/ directory is dev-only (never bundled).
Roadmap
- Slice 1 — shell + Director Rail + data model + dice engine (Year-Zero). ✅
- Slice 2 — NPC generator (offline genre tables) + art generator (offline pencil-art library). ✅
- Slice 3 — dice rule-packs (CoC d100, VANITY d6-pool, Panic & Glory, Dee Sanction) + tray pack selector. ✅
- Slice 4 — the clue safety-net (essential-clue gap tracker + fallbacks). ✅
- Slice 5 — the convention hub (all slots, live "live now / up next / done", deep-links into each scenario). ✅ All six Continuum 2026 slots ported and scheduled with real times.
- Native iPad wrapper — a Capacitor iOS shell around the PWA is scaffolded (config, scripts, integration). Generate + build it on a Mac with Xcode + CocoaPods: see
docs/native-ipad-wrapper.md. ✅ (config) / ⬜ (iOS build needs the toolchain)
The full design is now built. All §5 tray tools (dice with 6 packs, NPC, art with online Generate, clue-net, cast, break timer, parking-lot, wake-lock), the con hub, six ported Continuum scenarios, the markdown → scenario-data generator, and the native-wrapper scaffold.
Online art "Generate"
The art tray can generate new pencil art at the table and cache it into the searchable library (offline
thereafter). It needs a GM-configured image-gen endpoint — nothing is hardcoded and no key is baked
in. Paste your endpoint URL into the tray's ⚙ field (persisted). The endpoint receives POST { prompt }
and must reply JSON with an image under image | src | url | dataUrl (a data: URL makes the
result offline-cacheable), plus optional label / tags. With no endpoint or no network the Generate
button is disabled and the library stays fully searchable — the network is never load-bearing.
Docs
- Design:
docs/superpowers/specs/2026-07-20-gm-director-design.md - Slice 1 plan:
docs/superpowers/plans/2026-07-20-director-slice1.md
Personal convention-play tooling. System rule-references paraphrase their respective rulebooks for private table use.