Jo Van Eyck's Agentic Engineering Skills

Composable agent skills for agentic engineering. Each skill is self-contained that any compatible coding agent can discover and run.

Installs the skills into your project so you can read and tweak them:

npx skills@latest add jovaneyck/skills

You'll be prompted to pick which skills and which agents to install for.

claude plugin marketplace add jovaneyck/skills
claude plugin install jovaneyck-skills@jovaneyck

Turns a git change (two commit-ish references) into three C4 component diagrams — before, after, and a combined diff with a red/green/amber overlay — so a reviewer can validate the system-level impact of a change without reading every line.

Every node and edge is traceable to real code (file path + symbol); the diagram shows structure, not sequence, and stays honest about non-architectural changes.

A worked example (a synthetic order-processing codebase) lives in examples/c4-diffs/example/ with its rendered artifacts in examples/c4-diffs/artifacts/example/.

Trigger it with anything like "c4 diff between <sha> and <sha>", "diagram this PR architecturally", or "what changed structurally on this branch".

skills/<category>/<name>/SKILL.md   # the skills (catalog layout, grouped by category)
examples/<skill>/                   # sample codebases + rendered artifacts per skill
evals/<skill>/                      # skill-creator benchmark runs (not skills)

1. Create skills/<category>/<name>/SKILL.md (reuse an existing category or add a new one).
2. Give it YAML frontmatter with a name and a description rich in trigger phrases — the description is what the agent matches on to decide when to invoke the skill.
3. Keep any supporting docs in a references/ folder inside that skill.
4. Add a row to the Skills table above.

Skills are discovered by their SKILL.md, so keep non-skill material (evals, examples) out of skills/.