Imported from sxarsky/eval-ghost (apps/shade/AGENTS.md). Install upstream with npx skills add sxarsky/eval-ghost --skill shade. Copyright stays with the author.

Repository Guidelines

Project Structure & Module Organization

• src/components/ui/*: Atomic UI components (Radix/ShadCN-based). Each component should have a *.stories.tsx file next to it.
• src/components/layout/*: Reusable layout containers (Page, Heading, Header, ViewHeader, ErrorPage).
• src/components/features/*: Higher-level, opinionated components (e.g., PostShareModal, SourceTabs).
• src/hooks/*: Custom React hooks.
• src/lib/utils.ts: Shared utilities (class merging, formatting, chart helpers).
• src/providers/* and src/shade-app.tsx: Context + app wrapper that scopes styles to .shade.
• src/assets/*: Logos and custom icon SVGs (icons auto-exported via Icon).
• test/unit/*: Vitest tests. test/unit/utils/test-utils.tsx provides a render helper.
• Build artifacts: es/ (compiled ESM) and types/ (generated .d.ts). Storybook config lives in .storybook/.

Build, Test, and Development Commands

• pnpm build — Type declarations + Vite library build to es/.
• pnpm test — Type-checks then runs Vitest with coverage.
• pnpm test:unit / pnpm test:types — Run unit tests or TS type-checks only.
• pnpm lint — ESLint for source and tests (tailwindcss plugin enabled).
• pnpm storybook — Run Storybook locally. pnpm build-storybook — static export.

Coding Style & Naming Conventions

• React + TypeScript. Prefer composable components over heavy prop configuration.
• Filenames: ShadCN-generated files keep kebab-case; component identifiers use PascalCase.
• Functions/vars: camelCase. Keep file-scoped components in the same file.
• Always forward and merge className with cn(...). Use CVA for variants when useful.
• Tailwind is scoped via .shade; dark mode uses .dark. Follow ESLint and tailwindcss/* rules.

Component API Patterns

• Prefer compound subcomponents for multi‑region components (e.g., Header.Title, Header.Meta, Header.Actions) instead of many props.
• Keep parts small and focused; attach them as static properties and export as named exports.
• Expose Radix/HTML props where sensible; always include className and merge with cn(...).
• Demonstrate each part in Storybook stories (e.g., “With actions”, “With meta”).

Adding New Components

• Prefer ShadCN first: search for an equivalent and add via npx shadcn@latest add <component>. Follow the guardrails above to avoid accidental overwrites.
• Location & exports: place new UI components under src/components/ui and export them from src/index.ts.
• Storybook: add a sibling *.stories.tsx file with an overview (what/why) and stories showing different use cases/variants (sizes, states, important props). If you've added a ShadCN component then copy the examples from the ShadCN component documentation at https://ui.shadcn.com/docs/components/[component name].
• Implementation: forward className and merge with cn(...); use CVA for variants where appropriate.
• Verification: pnpm lint, pnpm test, plus pnpm storybook to visually validate stories before opening a PR.
• Important: Always run pnpm lint after making changes to fix any ESLint errors and warnings before committing.

Testing Guidelines (TBD)

We are finalizing a formal testing strategy.

Interim expectations:

• Use the existing setup (Vitest + Testing Library + jsdom) when adding tests.
• Location/patterns: test/unit/**/*.(test).(ts|tsx|js); use test/unit/utils/test-utils.tsx’s render when a wrapper is needed.
• For new UI components, prioritize comprehensive Storybook stories; add focused unit tests where they provide real value (e.g., hooks, utils, logic-heavy parts).
• No strict coverage threshold yet; run pnpm test locally to ensure the suite passes.

Commit & Pull Request Guidelines

• Commit messages are the release notes. Follow this structure:
  • 1st line: ≤ 80 chars, past tense, start with one of: Fixed/Changed/Updated/Improved/Added/Removed/Reverted/Moved/Released/Bumped/Cleaned.
  • 2nd line: blank.
  • 3rd line: magic word + absolute issue URL (e.g., ref https://linear.app/... or closes ...).
  • 4th+: explain the “why”/context behind the change.
• Gotchas: don’t use ref: (colon) — magic word must be followed by a space; Linear requires full URLs.
• Dependency bumps: focus the message on resulting user‑visible changes (no need to list which internal packages changed).
• PRs: describe changes, link issues, add screenshots/gifs for UI changes, and update/add stories.

Storybook Documentation for New Components

Refer to “Adding New Components” for the process. Story content should:

• Include a short overview (what the component does and primary use case).
• Demonstrate key variants and states (sizes, disabled/loading, critical props).
• Be minimal but representative; prefer CVA variants/props over ad‑hoc class overrides.
• Avoid obvious technical implementation details (e.g., which libraries are used). Prefer one‑line guidance per story explaining when to use that variant/size/state.

Notes for Contributors (and Agents)

• Do not rename ShadCN-generated files purely for casing.
• Use the @ alias for internal imports (e.g., @/lib/utils).
• When changing tokens/config, verify Storybook and a library build still succeed.
• When adding new components to Shade, always look for a ShadCN/UI equivalent and if it exists add it using npx.

ShadCN Component Installation Guardrails

• Never overwrite existing Shade components during npx shadcn@latest add <name> prompts. Choose “No” when asked to overwrite.
• Always work on a fresh branch and commit a clean baseline before running the installer so you can easily revert: git checkout -b chore/shadcn-add-<name>.
• If a component already exists in src/components/ui, generate the new version in a temporary workspace (scratch repo), then manually diff and port only the desired changes into the existing Shade file.
• After integrating, run pnpm lint, pnpm test, and verify in Storybook before merging.