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+---
+name: scaffold-exercises
+description: Scaffold numbered course exercises with problem, solution, and explainer folders in the AI Hero course format. Use when that format is requested or already established in the course.
+---
+
+# Scaffold Exercises
+
+Inspect the selected course's package manager, exercise layout, and lint script first. The conventions below describe the AI Hero format; follow an explicitly requested different format instead. Use the course's installed lint command; `pnpm ai-hero-cli internal lint` applies only when that tool and package manager are configured. If tooling is absent, check the files directly and report that lint was unavailable; do not install or initialize a course stack implicitly. Commit only when requested, staging just the task-owned exercise changes.
+
+## 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** - use the selected course's configured command
+5. **Fix any errors** - iterate until lint passes
+
+## Lint rules summary
+
+For courses using AI Hero, verify these conventions against the installed linter:
+
+- 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
+
+When renumbering or moving exercises:
+
+1. Use `git mv` (not `mv`) to rename directories - preserves git history
+2. Update the numeric prefix to maintain order
+3. Re-run lint after moves
+
+Example:
+
+```bash
+git mv exercises/01-retrieval/01.03-embeddings exercises/01-retrieval/01.04-embeddings
+```
+
+## Example: stubbing from a plan
+
+Given a plan like:
+
+```
+Section 05: Memory Skill Building
+- 05.01 Introduction to Memory
+- 05.02 Short-term Memory (explainer + problem + solution)
+- 05.03 Long-term Memory
+```
+
+Create:
+
+```bash
+mkdir -p exercises/05-memory-skill-building/05.01-introduction-to-memory/explainer
+mkdir -p exercises/05-memory-skill-building/05.02-short-term-memory/{explainer,problem,solution}
+mkdir -p exercises/05-memory-skill-building/05.03-long-term-memory/explainer
+```
+
+Then create readme stubs:
+
+```
+exercises/05-memory-skill-building/05.01-introduction-to-memory/explainer/readme.md -> "# Introduction to Memory"
+exercises/05-memory-skill-building/05.02-short-term-memory/explainer/readme.md -> "# Short-term Memory"
+exercises/05-memory-skill-building/05.02-short-term-memory/problem/readme.md -> "# Short-term Memory"
+exercises/05-memory-skill-building/05.02-short-term-memory/solution/readme.md -> "# Short-term Memory"
+exercises/05-memory-skill-building/05.03-long-term-memory/explainer/readme.md -> "# Long-term Memory"
+```