Design

Build type-safe validated forms using React Hook Form v7 and Zod v4. Single schema works on client and server with full TypeScript inference via z.infer. Use when building forms, multi-step wizards, or fixing uncontrolled warnings, resolver errors, useFieldArray issues.

Build React animations with Motion (Framer Motion) - gestures (drag, hover, tap), scroll effects, spring physics, layout animations, SVG. Bundle: 2.3 KB (mini) to 34 KB (full). Use when: drag-and-drop, scroll animations, modals, carousels, parallax. Troubleshoot: AnimatePresence exit, list performance, Tailwind conflicts, Next.js "use client".

Build backend AI with Vercel AI SDK v6 stable. Covers Output API (replaces generateObject/streamObject), speech synthesis, transcription, embeddings, MCP tools. Includes v4→v5 migration and 12 error solutions. Use when: implementing AI SDK v5/v6, migrating versions, troubleshooting AI_APICallError, Workers startup issues, or Output API validation errors.

Build React Native 0.76+ apps with Expo SDK 52+. Covers mandatory New Architecture (0.82+), React 19 changes, new CSS properties, and Swift iOS template. Use when building Expo apps, migrating to New Architecture, or fixing Fabric, TurboModule, propTypes, or Swift AppDelegate errors.

Build agentic AI with OpenAI Responses API - stateful conversations with preserved reasoning, built-in tools (Code Interpreter, File Search, Web Search), and MCP integration. Use when: building agents with persistent reasoning, using server-side tools, or migrating from Chat Completions for better multi-turn performance.

Build secure WordPress plugins with hooks, database interactions, Settings API, custom post types, and REST API. Covers Simple, OOP, and PSR-4 architecture patterns plus the Security Trinity. Use when creating plugins or troubleshooting SQL injection, XSS, CSRF vulnerabilities, or plugin activation errors.

Generate structured planning docs for web projects with context-safe phases, verification criteria, and exit conditions. Creates IMPLEMENTATION_PHASES.md plus conditional docs. Use when: starting new projects, adding major features, or breaking large work into manageable phases.

Build stateful chatbots with OpenAI Assistants API v2 - Code Interpreter, File Search (10k files), Function Calling. Deprecated (sunset August 2026); use openai-responses for new projects. Use when: maintaining legacy chatbots, implementing RAG with vector stores, or troubleshooting thread errors, vector store delays.

Build Python web apps with Flask using application factory pattern, Blueprints, and Flask-SQLAlchemy. Covers project structure, authentication, and configuration management. Use when: creating Flask projects, organizing blueprints, or troubleshooting circular imports, context errors, or registration.

Build Next.js 16 apps with App Router, Server Components/Actions, Cache Components ("use cache"), and async route params. Includes proxy.ts and React 19.2. Use when: building Next.js 16 projects, or troubleshooting async params (Promise types), "use cache" directives, parallel route 404s.

Implement or extend a user-facing workflow in a web application, integrating with existing backend APIs. Use when the feature is primarily a UI/UX change backed by existing APIs, affects only the web frontend, and requires following design system, routing, and testing conventions.

Add OAuth authentication to MCP servers on Cloudflare Workers. Uses @cloudflare/workers-oauth-provider with Google OAuth for Claude.ai-compatible authentication. Use when building MCP servers that need user authentication, implementing Dynamic Client Registration (DCR) for Claude.ai, or replacing static auth tokens with OAuth flows. Prevents CSRF vulnerabilities, state validation errors, and OAuth misconfiguration.

Build Python APIs on Cloudflare Workers using pywrangler CLI and WorkerEntrypoint class pattern. Includes Python Workflows for multi-step DAG automation. Prevents 8 documented errors. Use when: building Python serverless APIs, migrating Python to edge, or troubleshooting async errors, package compatibility, handler pattern mistakes.

Generate structured task lists from specs or requirements. IMPORTANT: After completing ANY spec via ExitSpecMode, ALWAYS ask the user: "Would you like me to generate a task list for this spec?" Use when user confirms or explicitly requests task generation from a plan/spec/PRD.

Build headless data tables with TanStack Table v8. Server-side pagination, filtering, sorting, and virtualization for Cloudflare Workers + D1. Use when building tables with large datasets, coordinating with TanStack Query, or fixing state management or performance issues.

Build MCP servers in Python with FastMCP to expose tools, resources, and prompts to LLMs. Supports storage backends, middleware, OAuth Proxy, OpenAPI integration, and FastMCP Cloud deployment. Prevents 25+ errors. Use when: creating MCP servers, or troubleshooting module-level server, storage, lifespan, middleware, or OAuth errors.

Set up Tailwind v4 with shadcn/ui using @theme inline pattern and CSS variable architecture. Four-step pattern: CSS variables, Tailwind mapping, base styles, automatic dark mode. Use when initializing React projects with Tailwind v4, or fixing colors not working, tw-animate-css errors, v3 migration.

Build semantic search with Cloudflare Vectorize V2. Covers async mutations, 5M vectors/index, 31ms latency, returnMetadata enum changes, and V1 deprecation. Prevents 8 errors including dimension mismatches. Use when: building RAG or semantic search, troubleshooting returnMetadata, V2 timing, metadata index, or dimension errors.

Build MCP servers on Cloudflare Workers - the only platform with official remote MCP support. TypeScript-based with OAuth, Durable Objects, and WebSocket hibernation. Prevents 22 documented errors. Use when: deploying remote MCP servers, implementing OAuth, or troubleshooting URL path mismatches, McpAgent exports, CORS issues.

Nine integrated slash commands for complete project lifecycle: /explore-idea, /plan-project, /plan-feature, /wrap-session, /continue-session, /workflow, /release, /brief, /reflect. Use when starting projects, managing sessions across context windows, capturing learnings, or preparing releases. Saves 35-55 minutes per lifecycle.