# Project Instructions for Claude
## CSS
Plain hand-written CSS, no Tailwind, no build step. Bun's HTML loader resolves
`` and inlines `@import` chains automatically for both
`bun run dev` and `bun run build`.
The CSS architecture:
- `public/css/main.css` - Main entry point, imports the partials and defines tokens/reset
- `public/css/workflow.css` - Commands section, glass terminal, case studies styles
- `public/css/gallery.css`, `skill-demos.css`, `problem-section.css` - section partials
Edit any of these directly and reload — no rebuild needed.
## Development Server
```bash
bun run dev # Bun dev server at http://localhost:3000
bun run preview # Build + Cloudflare Pages local preview
```
## Deployment
Hosted on Cloudflare Pages. Static assets served from `build/`, API routes handled via `_redirects` rewrites (JSON) and Pages Functions (downloads).
```bash
bun run deploy # Build + deploy to Cloudflare Pages
```
## Build System
The build system compiles skills and commands from `source/` to provider-specific formats in `dist/`:
```bash
bun run build # Build all providers
bun run rebuild # Clean and rebuild
```
Source files use placeholders that get replaced per-provider:
- `{{model}}` - Model name (Claude, Gemini, GPT, etc.)
- `{{config_file}}` - Config file name (CLAUDE.md, .cursorrules, etc.)
- `{{ask_instruction}}` - How to ask user questions
## Testing
```bash
bun run test # Run all tests
```
Unit tests (build, detector logic) run via `bun test`. Fixture tests (jsdom-based HTML detection) run via `node --test` because bun is too slow with jsdom. The `test` script handles this split automatically.
## CLI
The CLI lives in this repo under `bin/` and `src/`. Published to npm as `impeccable`.
```bash
npx impeccable detect [file-or-dir-or-url...] # detect anti-patterns
npx impeccable detect --fast --json src/ # regex-only, JSON output
npx impeccable live # start browser overlay server
npx impeccable skills install # install skills
npx impeccable --help # show help
```
The browser detector (`src/detect-antipatterns-browser.js`) is generated from the main engine. After changing `src/detect-antipatterns.mjs`, rebuild it:
```bash
bun run build:browser
```
**IMPORTANT**: Always use `node` (not `bun`) to run the detect CLI. Bun's jsdom implementation is extremely slow and will cause scans with HTML files to hang for minutes.
## Versioning
When bumping the version, update **all** of these locations to keep them in sync:
- `package.json` → `version`
- `.claude-plugin/plugin.json` → `version`
- `.claude-plugin/marketplace.json` → `plugins[0].version`
- `public/index.html` → hero version link text + new changelog entry (user-facing changes only, not internal build/tooling details)
## Adding New Skills
When adding a new user-invocable skill, update the command count in **all** of these locations:
- `public/index.html` → meta descriptions, hero box, section lead
- `public/cheatsheet.html` → meta description, subtitle, `commandCategories`, `commandRelationships`
- `public/js/data.js` → `commandProcessSteps`, `commandCategories`, `commandRelationships`
- `public/js/components/framework-viz.js` → `commandSymbols`, `commandNumbers`
- `public/js/demos/commands/` → new demo file + import in `index.js`
- `README.md` → intro, command count, commands table
- `NOTICE.md` → steering commands count
- `AGENTS.md` → intro command count
- `.claude-plugin/plugin.json` → description
- `.claude-plugin/marketplace.json` → metadata description + plugin description
## Evals Framework (private, gitignored)
There is a controlled eval framework at `evals/` that measures whether the `/impeccable` skill improves or harms AI-generated frontend design. It runs the same brief through a model with and without the skill loaded, fingerprints every generation, and aggregates the results into a bias report. The whole `evals/` directory is gitignored — it's intended to stay private (commercial).
**If you're picking up eval work in a new session, read `evals/AGENT.md` first.** It captures everything we've learned: model choices, sample size policy, lessons learned, common workflows, and gotchas. Don't try to reinvent the workflow from scratch — there's significant prior context.
### Quick orientation
- **Primary baseline model**: `gpt-5.4` with `--reasoning-effort medium`. Frontier intelligence at ~5-10× lower cost than high reasoning. **Do NOT use `--reasoning-effort high`** unless you specifically need it — reasoning tokens count against `max_completion_tokens` and burn ~$1-2/file with no quality benefit for our use case.
- **Secondary validation model**: `qwen/qwen3.6-plus` via OpenRouter. Cheap-ish, decent design quality, no reasoning controls.
- **Do NOT use Haiku as a primary eval target.** It ignores most negative rules in the skill. We learned this the hard way — it sent us down many wrong paths early on.
- **Sample size policy**: n=10 per niche for scratch iteration, **n=20 for sweep validation (the standard)**, n=50 reserved for the final published baseline. n=20 is the smallest sample where rare detector findings stabilize and A/B comparisons are statistically meaningful.
### Quick commands
```bash
# Always start the local server first — the gallery/viewer can't load via file:// (CORS)
bun run evals/runner/serve.ts
# Standard workflow: generate → detect → aggregate → snapshot
bun run evals/runner/run.ts --with-refs --model gpt-5.4 --reasoning-effort medium
bun run evals/runner/detect.ts
bun run evals/runner/aggregate.ts
bun run evals/runner/snapshot.ts --title "..." --note "..."
# Cheap targeted iteration (does not pollute current/)
bun run evals/runner/run.ts --with-refs --scratch my-test \
--niches 06 --n 10 --condition skill-on --model qwen/qwen3.6-plus
# View results in browser
open http://localhost:8723/viewer.html
```
### Critical rules
- **Always run a small smoke test (n=2-5 on one niche) before any sweep.** Rate degrades over long runs and time estimates can be off by 10-20×. We once burned 11+ hours on a sweep estimated to take 40 minutes.
- **Background long runs.** Use `run_in_background: true` for any sweep over ~50 generations. The runner is resumable so killing and restarting is safe.
- **Don't mix prompt versions in the same dataset.** The variant.json safety check enforces this for `current/` (must pass `--rebuild-skill-on` after a prompt edit). Scratch dirs auto-wipe on prompt change.
- **Snapshot first, change second.** Always have a known reference point in `evals/output/snapshots/` before editing the skill, so you can compare before/after.
- **The user is the source of truth on aesthetic quality.** The fingerprinter and detector are useful signals but do not measure "is this design good?" Have the user spot-check the gallery for any meaningful change.
See `evals/AGENT.md` for the full reference: detailed model comparison table, complete lessons learned, all common workflows, and the list of gotchas.