Development and Engineering Skills
Build, test, and debug
| Skill | Pick it when | Important distinction |
|---|
$implement | A PRD, issue, or agreed plan is ready to build. | It executes; it is not the discovery phase. |
$tdd | Behavior can be tested through a stable public interface and you want red-green-refactor. | Do not force it onto exploratory work with no stable seam. |
$systematic-debugging | Something is broken and the root cause is unknown. | Start here before proposing fixes. |
$diagnosing-bugs | A bug is especially hard, intermittent, or performance-related. | It overlaps with systematic debugging; choose one lead. |
$qa | A person wants to report several problems conversationally and create issues. | This is issue capture, not an automated test runner. |
$setup-pre-commit | You want commit-time formatting, type checks, and tests. | It changes repository tooling. |
$migrate-to-shoehorn | TypeScript tests need migration away from as assertions. | It is a narrow migration tool. |
Architecture and domain
| Skill | Best use |
|---|
$codebase-design | Shape one module boundary or API using deep-module principles. |
$design-an-interface | Generate and compare multiple different module interfaces. |
$improve-codebase-architecture | Scan the broader repository for architectural opportunities. |
$domain-modeling | Clarify domain concepts, boundaries, terminology, and decisions over time. |
$ubiquitous-language | Extract a focused DDD glossary from the current conversation. |
$request-refactor-plan | Produce a safe, incremental refactor plan. |
$graphify | Build and query a persistent relationship map for a large or unfamiliar codebase. |
Reviews and repository operations
| Skill | Use it for |
|---|
$review | Default review: documented standards and requested behavior as separate axes. |
$thermo-nuclear-code-quality-review | An intentionally severe maintainability and abstraction audit. |
$vercel-react-best-practices | React/Next.js performance implementation or review. |
$resolving-merge-conflicts | An active merge or rebase conflict. |
$git-guardrails-claude-code | Install hooks that block dangerous Git commands in Claude Code. |
Typical development flow: understand the domain, design the smallest stable interface, implement one slice, then review. Use fewer skills when the change is already clear.