Color for developers - color spaces, accessibility contrast, palette generation, CSS color functions, design tokens, dark mode, and CVD simulation. Use for: color, colour, palette, contrast, accessibility, WCAG, APCA, OKLCH, OKLAB, HSL, color picker, color-mix, dark mode colors, design tokens, color system, color scale, color ramp, gradient, CVD, color blind, gamut, P3, sRGB, color naming, color harmony, color temperature, semantic colors.

Analyze codebase with tokei (fast line counts by language) and difft (semantic AST-aware diffs). Get quick project overview without manual counting. Triggers on: how big is codebase, count lines of code, what languages, show semantic diff, compare files, code statistics.

Patterns for building production-quality CLI tools with predictable behavior, parseable output, and agentic workflows. Triggers: cli tool, command line tool, build cli, cli patterns, agentic cli, cli design, typer cli, click cli.

Claude Code hook system for pre/post tool execution. Triggers on: hooks, PreToolUse, PostToolUse, hook script, tool validation, audit logging.

Run Claude Code programmatically without interactive UI. Triggers on: headless, CLI automation, --print, output-format, stream-json, CI/CD, scripting.

Troubleshoot Claude Code extensions and behavior. Triggers on: debug, troubleshoot, not working, skill not loading, hook not running, agent not found.

CI/CD pipeline patterns with GitHub Actions, release automation, and testing strategies. Use for: github actions, workflow, CI, CD, pipeline, deploy, release, semantic release, changesets, goreleaser, matrix, cache, secrets, environment, artifact, reusable workflow, composite action.

Authentication and authorization patterns - JWT, OAuth2, sessions, RBAC, ABAC, passkeys, and MFA. Use for: authentication, authorization, jwt, oauth, oauth2, session, login, rbac, abac, passkey, mfa, totp, api key, token, auth, cookie, csrf, cors credentials, bearer token, refresh token, oidc.

Atom of Thoughts (AoT) reasoning - decompose complex problems into atomic units with confidence tracking and backtracking. For genuinely complex reasoning, not everyday questions. Triggers on: atomise, complex reasoning, decompose problem, structured thinking, verify hypothesis.

Astro framework patterns, islands architecture, content collections, rendering strategies, and deployment. Use for: astro, islands architecture, content collections, astro cloudflare, view transitions, partial hydration, astrojs, SSG, SSR, hybrid rendering, astro adapter.

API design patterns for REST, gRPC, and GraphQL. Use for: api design, REST, gRPC, GraphQL, protobuf, schema design, api versioning, pagination, rate limiting, error format, OpenAPI, API authentication, JWT, OAuth2, API gateway, webhook, idempotency.

Review UI code for Web Interface Guidelines compliance. Use when asked to "review my UI", "check accessibility", "audit design", "review UX", or "check my site against best practices".

Defines a practical testing strategy for TypeScript and JavaScript using Vitest across unit, integration, and type-level tests. Use when adding features, refactoring, or preventing regressions with fast feedback loops.

All packages must have the same version. Use changesets for coordinated version bumps. Never version packages independently.

React Native and Expo best practices for building performant mobile apps. Use when building React Native components, optimizing list performance, implementing animations, or working with native modules. Triggers on tasks involving React Native, Expo, mobile performance, or native platform APIs.

React and Next.js performance optimization guidelines from Vercel Engineering. This skill should be used when writing, reviewing, or refactoring React/Next.js code to ensure optimal performance patterns. Triggers on tasks involving React components, Next.js pages, data fetching, bundle optimization, or performance improvements.

React composition patterns that scale. Use when refactoring components with boolean prop proliferation, building flexible component libraries, or designing reusable APIs. Triggers on tasks involving compound components, render props, context providers, or component architecture. Includes React 19 API changes.

Use immediately when the user requests any implementation, code change, feature addition, fix, or modification. Gates code writing behind a backlog draft document. Read-only exploration is always permitted.

Applies Robota's preferred workflow for trust-boundary validation, strict typing, quality gates, and owner-based SSOT reuse. Use when adding or reviewing type contracts, boundary parsing, shared contract ownership, or running quality checks.

Kent Beck's TDD workflow. Use when writing new code or modifying existing behavior. Enforces the Red-Green-Refactor cycle with small, verifiable steps.

Track work using task files in .agents/tasks/. Use when starting, progressing, or completing a task to maintain a persistent record of work.

Provide Tailwind truncation patterns for single-line and multi-line text. Use when discussing text ellipsis, truncation, or line-clamp usage.

Designs finite state machines as pure, declarative transition tables with guards and actions. Use when modeling lifecycle states, status flows, or any system with discrete states and controlled transitions.

Use when creating a new SPEC.md or incrementally updating an existing one. Covers both initial authoring and the ongoing incremental-update workflow that keeps the spec live.