Deploy applications and websites to Vercel. Use when the user requests deployment actions like "deploy my app", "deploy and give me the link", "push this live", or "create a preview deployment". Do NOT use for deploying to Netlify, Cloudflare, or Render (use their respective skills).

Groups existing components into logical business domains to plan service-based architecture. Use when asking "which components belong together?", "group these into services", "organize by domain", "component-to-domain mapping", or planning service extraction from an existing codebase. Do NOT use for identifying new domains from scratch (use domain-analysis) or analyzing coupling (use coupling-analysis).

Apply modern web development best practices for security, compatibility, and code quality. Use when asked to "apply best practices", "security audit", "modernize code", "code quality review", or "check for vulnerabilities". Do NOT use for accessibility (use web-accessibility), SEO (use seo), performance (use core-web-vitals), or comprehensive multi-area audits (use web-quality-audit).

Three.js post-processing - EffectComposer, bloom, DOF, screen effects. Use when adding visual effects, color grading, blur, glow, or creating custom screen-space shaders.

Three.js interaction - raycasting, controls, mouse/touch input, object selection. Use when handling user input, implementing click detection, adding camera controls, or creating interactive 3D experiences.

Three.js geometry creation - built-in shapes, BufferGeometry, custom geometry, instancing. Use when creating 3D shapes, working with vertices, building custom meshes, or optimizing with instanced rendering.

Three.js animation - keyframe animation, skeletal animation, morph targets, animation mixing. Use when animating objects, playing GLTF animations, creating procedural motion, or blending animations.

Extends classic SZZ with semantic code understanding to reduce false positives and improve accuracy of bug-introducing commit identification. Use after classic SZZ has produced candidates, when SZZ precision is too low for the task, or when the user needs high-confidence bug-introduction data.

Review Rust code changes for unsafe correctness, documentation quality, and C-to-Rust porting fidelity. Use this when you want to review Rust changes before merging.

Guidelines for writing Python flow tests (end-to-end behavioral tests). Use this when writing new Python tests in tests/pytests/.

Check which Rust lines are not covered by Rust tests. Use this when you developed new Rust code and want to ensure it is tested.

Implements Manus-style file-based planning for complex tasks. Creates task_plan.md, findings.md, and progress.md. Use when starting complex multi-step tasks, research projects, or any task requiring >5 tool calls.

Validates Conductor project artifacts for completeness, consistency, and correctness. Use after setup, when diagnosing issues, or before implementation to verify project context.

Structured guide for setting up A/B tests with mandatory gates for hypothesis, metrics, and execution readiness.

Applies proven testing patterns — Arrange-Act-Assert (AAA), Given-When-Then, Test Data Builders, Object Mother, parameterized tests, fixtures, spies, and test doubles — to help write maintainable, reliable, and readable test suites. Use when the user asks about writing unit tests, integration tests, or end-to-end tests; structuring test cases or test suites; applying TDD or BDD practices; working with mocks, stubs, spies, or fakes; improving test coverage or reducing flakiness; or needs guidance on test organization, naming conventions, or assertions in frameworks like Jest, Vitest, pytest, or similar.

Runs approved Harness Engineering plans in recurring phases: check live state, confirm continuation authority, execute only the active he-work slice, verify gates, update Linear only with approval, and stop before unsafe staging or closure. Use when a plan, issue, or PR needs continued phase-by-phase execution.

Final visual polish for an existing UI without redesigning it. Use after structure is clear, when asked to improve spacing, alignment, text hierarchy, readability, shadows, highlights, effects, action placement, or overall production feel. For screen structure, layer naming, code handoff, preview scenes, or animation planning, use pencil-ui-structure first.

Convert Pencil `.pen` design files and named Pencil node IDs into production frontend code. Use when asked to implement, migrate, reproduce, or refine a Pencil/Figma-like visual design in code, especially for responsive artboards, glassmorphism, typography matching, background image layers, design tokens, or visual fidelity debugging against Pencil node IDs.

Best practices for writing, reviewing, and refactoring React Flow / @xyflow/react v12 canvases. Use when work touches React Flow components, custom nodes, custom edges, handles, node data typing, viewport controls, MiniMap/Background/Panel usage, NodeToolbar, NodeResizer, or workflow-builder review tasks.