Frontend

Build type-safe D1 databases with Drizzle ORM for Cloudflare Workers. Includes schema definition, migrations with Drizzle Kit, relations, and D1 batch API patterns. Prevents 12 errors including SQL BEGIN failures. Use when: defining D1 schemas, managing migrations, writing type-safe queries, implementing relations or prepared statements, using batch API for transactions, or troubleshooting D1_ERROR, BEGIN TRANSACTION, foreign keys, migration apply, or schema inference errors. Prevents 12 documented issues: D1 transaction errors (SQL BEGIN not supported), foreign key constraint failures during migrations, module import errors with Wrangler, D1 binding not found, migration apply failures, schema TypeScript inference errors, prepared statement caching issues, transaction rollback patterns, TypeScript strict mode errors, drizzle.config.ts not found, remote vs local database confusion, and wrangler.toml vs wrangler.jsonc mixing. Keywords: drizzle orm, drizzle d1, type-safe sql, drizzle schema, drizzle migrations, drizzle kit, orm cloudflare, d1 orm, drizzle typescript, drizzle relations, drizzle transactions, drizzle query builder, schema definition, prepared statements, drizzle batch, migration management, relational queries, drizzle joins, D1_ERROR, BEGIN TRANSACTION d1, foreign key constraint, migration failed, schema not found, d1 binding error

Build and deploy Streamlit apps natively in Snowflake with production-ready templates. Covers project scaffolding (snowflake.yml, environment.yml), Snowpark session patterns, multi-page structure, and Marketplace publishing as Native Apps. Use when building data apps on Snowflake, deploying Streamlit in Snowflake (SiS), or publishing to Snowflake Marketplace. Prevents package channel errors, outdated Streamlit versions, and authentication issues.

Build Google Chat bots and webhooks with Cards v2, interactive forms, Spaces/Members/Reactions APIs, and Cloudflare Workers integration. Includes webhook handlers, card builders, form validation, bearer token verification, rate limit handling, and dialog patterns. Use when creating Chat bots, managing spaces/members programmatically, workflow automation, or interactive forms, or troubleshooting bearer token errors, rate limit 429 errors, card schema validation, or webhook verification failures.

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.

Build Python APIs on Cloudflare Workers using pywrangler CLI and WorkerEntrypoint class pattern. Includes Python Workflows for multi-step DAG automation with @step.do decorators. Use when: building Python serverless APIs, migrating Python code to edge, using Python ML libraries, or creating durable workflows. Prevents async errors, package compatibility issues, handler pattern mistakes.

Optimize Next.js App Router data fetching by converting slow client-side fetching to fast server-side fetching using React Server Components (RSC). Use when: - User reports slow initial page load with loading spinners - Page uses useEffect + useState for data fetching - StoreContext/useStore pattern causes waterfall fetching - Need to improve SEO (content not in initial HTML) - Converting "use client" pages to Server Components Triggers: "slow loading", "optimize fetching", "SSR data", "RSC optimization", "remove loading spinner", "server-side fetch", "convert to server component", "data fetch lambat", "loading lama"

Track progress across work sessions using SESSION.md with git checkpoints and concrete next actions. Converts IMPLEMENTATION_PHASES.md into trackable session state with phase status, progress markers, and recovery points. Use when: starting projects after planning phase, resuming work after context clears, managing multi-phase implementations, or troubleshooting lost context, missing progress tracking, or unclear next steps.

Build AI applications with OpenAI Agents SDK - text agents, voice agents (realtime), multi-agent workflows with handoffs, tools with Zod schemas, input/output guardrails, structured outputs, and streaming. Deploy to Cloudflare Workers, Next.js, or React with human-in-the-loop patterns. Use when: building text-based agents with tools and Zod schemas, creating realtime voice agents with WebRTC/WebSocket, implementing multi-agent workflows with handoffs between specialists, setting up input/output guardrails for safety, requiring human approval for critical actions, streaming agent responses, deploying agents to Cloudflare Workers or Next.js, or troubleshooting Zod schema type errors, MCP tracing failures, infinite loops (MaxTurnsExceededError), tool call failures, schema mismatches, or voice agent handoff constraints.

Build stateless MCP servers with TypeScript on Cloudflare Workers using @modelcontextprotocol/sdk. Provides patterns for tools, resources, prompts, and authentication (API keys, OAuth, Zero Trust). Use when exposing APIs to LLMs, integrating Cloudflare services (D1, KV, R2, Vectorize), or troubleshooting export syntax errors, unclosed transport leaks, or CORS misconfigurations.

Integrate Redis-compatible Vercel KV for caching, session management, and rate limiting in Next.js applications. Powered by Upstash with strong consistency and TTL support. Use when implementing cache strategies, storing temporary data with expiration, building rate limiters, or troubleshooting missing environment variables, serialization errors, or rate limit issues.

Build stateful chatbots with OpenAI Assistants API v2 - Code Interpreter, File Search (10k files), Function Calling. ⚠️ Deprecated (sunset August 26, 2026); use openai-responses for new projects. Use when: maintaining legacy chatbots, implementing RAG with vector stores, or troubleshooting "thread has active run", vector store delays, polling timeouts, or file upload errors.

Build type-safe, file-based React routing with TanStack Router. Supports client-side navigation, route loaders, and TanStack Query integration. Use when implementing file-based routing patterns, building SPAs with TypeScript routing, or troubleshooting devtools dependency errors, type safety issues, or Vite bundling problems.

Build type-safe validated forms in React using React Hook Form and Zod schema validation. Single schema works on both client and server for DRY validation with full TypeScript type inference via z.infer. Use when: building forms with validation, integrating shadcn/ui Form components, implementing multi-step wizards, handling dynamic field arrays with useFieldArray, or fixing uncontrolled to controlled warnings, resolver errors, async validation issues.

Build document Q&A and searchable knowledge bases with Google Gemini File Search - fully managed RAG with automatic chunking, embeddings, and citations. Upload 100+ file formats (PDF, Word, Excel, code), configure semantic search, and query with natural language. Use when: building document Q&A systems, creating searchable knowledge bases, implementing semantic search without managing embeddings, indexing large document collections (100+ formats), or troubleshooting document immutability errors (delete+re-upload required), storage quota issues (3x input size for embeddings), chunking configuration (500 tokens/chunk recommended), metadata limits (20 key-value pairs max), indexing cost surprises ($0.15/1M tokens one-time), operation polling timeouts (wait for done: true), force delete errors, or model compatibility (Gemini 2.5 Pro/Flash only).

Build with OpenAI's stateless APIs - Chat Completions (GPT-5.2, GPT-5.1, o3, o4-mini), Realtime API (voice), Batch API (50% savings), Embeddings, Images (DALL-E 3), Audio (Whisper + TTS), and Moderation. Node.js SDK and fetch for Cloudflare Workers. Use when: implementing chat with GPT-5.2/5.1/o3/o4-mini, Realtime voice API (WebSocket), Batch API for cost savings, xhigh reasoning (GPT-5.2), streaming responses, function calling/tools, structured outputs, embeddings for RAG, DALL-E 3 images, Whisper transcription, TTS (13 voices), or troubleshooting rate limits (429), API keys (401), streaming errors.

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

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

Build sophisticated React animations with Motion (formerly Framer Motion) - declarative animations, gestures (drag, hover, tap), scroll effects, spring physics, layout animations, and SVG manipulation. Optimize bundle size with LazyMotion (4.6 KB) or useAnimate mini (2.3 KB). Use when: adding drag-and-drop interactions, creating scroll-triggered animations, implementing modal dialogs with transitions, building carousels with momentum, animating page/route transitions, creating parallax hero sections, implementing accordions with smooth expand/collapse, or optimizing animation bundle sizes. For simple list animations, use auto-animate skill instead (3.28 KB vs 34 KB). Troubleshoot: AnimatePresence exit not working, large list performance issues, Tailwind transition conflicts, Next.js "use client" errors, scrollable container layout issues, or Cloudflare Workers build errors (resolved Dec 2024).

Proactively analyze user requests at the start of conversations to determine task type, assess prompt quality, and intelligently recommend which skills to activate. Should activate for ALL user requests to ensure optimal workflow. Evaluates clarity, specificity, and completeness to suggest prompt-optimizer when needed. Identifies UI design tasks for ui-analyzer and component requests for react-component-generator. Acts as intelligent skill coordinator.

Generate React components following best practices with TypeScript, Tailwind CSS, and Zustand state management. Use this skill when the user requests creating React components, UI elements, or mentions component generation. Supports common component patterns including basic components, forms, lists, cards, buttons, modals, and stateful components with Zustand integration.