Claude Code Knowledge

SEO optimization patterns for web applications. Use when adding structured data, meta tags, Open Graph, sitemaps, or optimizing Core Web Vitals.

Documentation patterns for software projects. Use when writing JSDoc, OpenAPI specs, ADRs, READMEs, CHANGELOGs, or API documentation.

Zod validation patterns and schema definitions. Use when implementing validation, type inference, custom validators, or form/API integration with Zod.

Hono web framework patterns for middleware, routes, and validation. Use when building APIs with Hono, zValidator, or factory-based CRUD.

Internationalization and localization patterns. Use when adding multi-language support, RTL layouts, pluralization, or number/date formatting.

Astro patterns for island architecture, routing, content collections, and SSR/SSG. Use when building content-driven websites with Astro.

CI/CD pipeline patterns for GitHub Actions. Use when setting up workflows, build caching, matrix builds, or deployment strategies.

Environment variable validation and typing patterns. Use when managing .env files, ensuring type-safe env access, or catching missing variables at startup.

React component and hook patterns. Use when building functional components, custom hooks, compound components, or handling code splitting and error boundaries.

Security audit patterns for OWASP Top 10 compliance. Use when conducting security reviews, penetration testing, or auditing authentication and data protection.

API endpoint testing methodology. Use when writing tests for REST APIs, validating error handling, schema validation, and authentication.

Docker containerization patterns. Use when writing Dockerfiles, multi-stage builds, docker-compose, or container security hardening.

Pre-coding design process and aesthetic principles. Use when designing UIs, working with typography, color theory, motion design, or design tokens.

NestJS patterns for modules, DI, guards, pipes, and interceptors. Use when building scalable server-side applications with NestJS.

Next.js App Router patterns for Server/Client Components, data fetching, caching, and server actions. Use when building Next.js applications.

Prisma patterns for schema design, Client API, migrations, and relations. Use when building database layers with Prisma ORM.

Test-Driven Development with RED-GREEN-REFACTOR cycle. Use when writing tests before implementation or practicing TDD methodology.

Web application testing strategy covering unit, integration, component, E2E, and accessibility tests. Use when building test suites for web apps.

Drizzle ORM patterns for schema, relations, queries, and migrations. Use when building database layers with Drizzle on PostgreSQL.

Security testing methodology for authentication, authorization, and injection prevention. Use when validating security measures or testing OWASP compliance.

Zustand state management patterns with middleware. Use when creating stores, slice patterns, persist/immer middleware, or computed values.

Conventional commit message generation. Use when creating commit messages, analyzing changed files, or formatting git commands.

JSON data validation, audit, and quality scoring. Use when reviewing API responses, configuration files, data exports, or schema compliance.

Monorepo architecture patterns with modern tooling. Use when setting up Turborepo, pnpm workspaces, Nx, or managing shared packages.

Performance audit patterns for database, API, frontend, and Core Web Vitals. Use when identifying bottlenecks or optimizing application performance.

React performance optimization rules prioritized by impact. Use when optimizing re-renders, bundle size, lazy loading, or profiling React apps.

Shadcn UI component patterns for theming, variants, and accessibility. Use when implementing shadcn/ui components, cva variants, or dark mode.

TanStack ecosystem overview and shared patterns. Use when working with TanStack libraries or understanding headless UI architecture.

Vercel deployment and optimization patterns. Use when deploying to Vercel, configuring edge functions, ISR, or build optimization.

Markdown formatting rules and automated fixes. Use when formatting documentation, applying linting rules, or ensuring consistent markdown standards.

WCAG 2.1 AA accessibility audit patterns. Use when conducting accessibility reviews, ensuring inclusive UX, or auditing ARIA and keyboard navigation compliance.

Performance testing methodology across all application layers. Use when benchmarking, validating performance budgets, or measuring optimization impact.

Converts design-cloner HTML/CSS output into framework-specific components. Use after running the design-cloner agent to generate React, Vue, Svelte, Solid, or Astro components from the HTML/CSS clone.

Acceptance criteria validation patterns. Use when verifying feature implementations against specs, UI/UX compliance, or test coverage requirements.

Standardized error handling patterns for all application layers. Use when designing error hierarchies, recovery strategies, or error boundaries.

GitHub Actions CI/CD patterns. Use when creating workflows, matrix builds, caching strategies, or deployment pipelines.

TanStack Query patterns for data fetching and server state. Use when implementing queries, mutations, cache invalidation, or optimistic updates.

TanStack Table patterns for headless, type-safe tables. Use when building sortable, filterable, paginated tables with column definitions.

React Hook Form patterns with Zod validation. Use when building forms with field arrays, controlled components, file uploads, or async validation.

TanStack Router patterns for type-safe routing. Use when defining routes, data loaders, search parameters, or authenticated routes.

Mermaid diagram creation patterns. Use when creating flowcharts, sequence diagrams, ER diagrams, class diagrams, or state diagrams.

57 performance optimization rules for React and Next.js from Vercel Engineering. Use when writing, reviewing, or refactoring React/Next.js code for optimal performance. Rules are prioritized by impact across 8 categories.