Design e Frontend

Defines REST and GraphQL API contracts including endpoints, request/response schemas, auth flows, and versioning strategy. Use when designing a new API, reviewing an API spec, or when the user mentions API design, OpenAPI, or endpoint contracts.

Designs event-sourced systems with CQRS, event stores, projections, and eventual consistency patterns. Use when architecting event-driven systems or when the user mentions event sourcing, CQRS, event store, or domain events.

Improve and iterate on existing Claude Code skills based on usage feedback, test results, or changing requirements. Handles under/over-triggering fixes, instruction refinement, new sub-skill addition, and architecture evolution. Use when user says "improve skill", "fix skill", "skill not triggering", "skill triggers too much", "update skill", or "evolve skill".

Orchestrates the UI team of ux-designer and ui-programmer to design, implement, and polish a UI feature from wireframe to final implementation. Use when a UI component or page needs both design and engineering coordination.

Conducts a structured technical deep-dive to gather detailed requirements, constraints, and decisions from the user. Use when starting a complex feature or when the user wants to be asked structured clarifying questions before implementation.

Next.js App Router specific patterns — Server Components, Client Components boundary, parallel fetching, bundle analysis, a11y. Use ONLY for Next.js 13+ App Router projects. For generic React/Vue patterns, use `frontend-patterns` instead.

Generates high-fidelity architecture diagrams, sequence flows, and component maps for SDD projects. Use when finalizing a design phase, documenting system architecture, or visualizing agentic workflows. Default style: Style 6 (Claude Official).

Benchmark Claude Code skill performance with variance analysis, tracking pass rate, execution time, and token usage across iterations. Runs multiple trials per eval for statistical reliability, aggregates results into benchmark.json, and generates comparison reports between skill versions. Use when user says "benchmark skill", "measure skill performance", "skill metrics", "compare skill versions",

Provides Radix UI patterns for building accessible design systems with headless components, theming, and compound component architecture. Use when building UI with Radix UI primitives or when the user mentions Radix UI, headless components, or accessible component libraries.

Convert Claude Code skills to work on OpenAI Codex, Google Gemini CLI, Google Antigravity, and Cursor. Analyzes platform-specific features, generates target files (openai.yaml, AGENTS.md, GEMINI.md, .mdc rules), adapts frontmatter, converts MCP config, and produces compatibility reports. Use when user says "convert skill", "port skill", "multi-platform", "skill for codex", "skill for gemini", "ski

Guidelines and procedures for creating comprehensive UI Specifications from PRDs and prototypes.

Reads production/traces/agent-metrics.jsonl and displays a per-agent performance summary table for the current or a specified session. Highlights agents with high error rates or OPEN circuit breaker state.