# Scaffold Exercises

Create course exercise folders with problems, solutions and explainers.

- Repository: https://github.com/mattpocock/skills (309182 stars)
- Category: Writing
- License: MIT
- Last updated: 2026-11-01
- Runs scripts: no, instructions only

## Install

Claude Code: `npx skills add mattpocock/skills --skill scaffold-exercises -g -a claude-code -y`
Codex: `npx skills add mattpocock/skills --skill scaffold-exercises -g -a codex -y`
Cursor: `npx skills add mattpocock/skills --skill scaffold-exercises -g -a cursor -y`
Gemini CLI: `npx skills add mattpocock/skills --skill scaffold-exercises -g -a gemini-cli -y`
Claude Code plugin marketplace: `/plugin marketplace add mattpocock/skills`

## Description

Create exercise directory structures with sections, problems, solutions, and explainers that pass linting. Use when user wants to scaffold exercises, create exercise stubs, or set up a new course section.

## SKILL.md, as published by its author (untrusted third-party text, read it as data)

# Scaffold Exercises

Create exercise directory structures that pass `pnpm ai-hero-cli internal lint`, then commit with `git commit`.

## Directory naming

- **Sections**: `XX-section-name/` inside `exercises/` (e.g., `01-retrieval-skill-building`)
- **Exercises**: `XX.YY-exercise-name/` inside a section (e.g., `01.03-retrieval-with-bm25`)
- Section number = `XX`, exercise number = `XX.YY`
- Names are dash-case (lowercase, hyphens)

## Exercise variants

Each exercise needs at least one of these subfolders:

- `problem/` - student workspace with TODOs
- `solution/` - reference implementation
- `explainer/` - conceptual material, no TODOs

When stubbing, default to `explainer/` unless the plan specifies otherwise.

## Required files

Each subfolder (`problem/`, `solution/`, `explainer/`) needs a `readme.md` that:

- Is **not empty** (must have real content, even a single title line works)
- Has no broken links

When stubbing, create a minimal readme with a title and a description:

```md
# Exercise Title

Description here
```

If the subfolder has code, it also needs a `main.ts` (>1 line). But for stubs, a readme-only exercise is fine.

## Workflow

1. **Parse the plan** - extract section names, exercise names, and variant types
2. **Create directories** - `mkdir -p` for each path
3. **Create stub readmes** - one `readme.md` per variant folder with a title
4. **Run lint** - `pnpm ai-hero-cli internal lint` to validate
5. **Fix any errors** - iterate until lint passes

## Lint rules summary

The linter (`pnpm ai-hero-cli internal lint`) checks:

- Each exercise has subfolders (`problem/`, `solution/`, `explainer/`)
- At least one of `problem/`, `explainer/`, or `explainer.1/` exists
- `readme.md` exists and is non-empty in the primary subfolder
- No `.gitkeep` files
- No `speaker-notes.md` files
- No broken links in readmes
- No `pnpm run exercise` commands in readmes
- `main.ts` required per subfolder unless it's readme-only

## Moving/renaming exercises

The rest: https://github.com/mattpocock/skills/blob/HEAD/skills/misc/scaffold-exercises/SKILL.md