Create distinctive, production-grade frontend interfaces with high design quality. Use this skill when the user asks to build web components, pages, or applications. Generates creative, polished code that avoids generic AI aesthetics. Do NOT trigger during: design spec creation (use design-brief-builder); visual prototype generation (use design-maker).
End-to-end testing skill (includes merged agent-browser capabilities). For web/SPA projects: launches parallel sub-agents to research codebase, then uses Playwright scripts (preferred), Playwright MCP interactive mode, or agent-browser CLI to test every user journey. For non-web types: redirects to corresponding test strategy or backend-test skill. Run after /execute to validate before code review.
Backend test execution skill covering REST API integration tests, database tests, and mock strategies. USE THIS SKILL when creating backend test files, writing API workflow tests, setting up database test fixtures with transaction rollback, or determining mock vs integration test boundaries. Covers unit tests for service/util/handler layers, integration tests for API endpoints, and database migration verification.
Enforce API Contract-First development workflow between backend and frontend. Generates and validates a shared OpenAPI spec, ensures frontend services/types match backend data models, catches parameter naming mismatches (case conventions, aliasing), missing endpoints, and type inconsistencies. USE THIS SKILL whenever: building new API endpoints, creating frontend service layers, adding new pages that call APIs, modifying data models/Request/Response classes, changing controller method signatures, or when the user mentions "API contract", "frontend-backend mismatch", "field mapping", "OpenAPI", "swagger", or "API consistency". Also trigger when creating or modifying files in API controller, service, or data transfer directories.