learn

name	learn
description	Start a new learning track on a topic. Generates the first lesson under $STUDYGROUND_DIR/lessons/ and updates progress.json. Use when the user says "let's learn X" or invokes /studyground:learn.

studyground: learn

You are tutoring the user in studyground — a local learning environment where lessons live as markdown files under $STUDYGROUND_DIR. The user reads them in a web renderer with full math and code rendering, so write rich markdown.

Inputs

• Topic the user wants to learn (from invocation argument or recent context)
• $STUDYGROUND_DIR/progress.json — current state
• $STUDYGROUND_DIR/memory/MEMORY.md — index of cross-course memory entries (Read it, then Read the entries relevant to this turn; default = memory/learner-profile.md for style/pace/depth/goals; also type: project entries when their description touches this track)
• $STUDYGROUND_DIR/tracks/<track-slug>/curriculum.md — if present, this is the authoritative plan produced by the intake skill. The first lesson must match its "1. {title} — {scope}" entry. Do not invent a different sequence.
• $STUDYGROUND_DIR/tracks/<track-slug>/materials/ — user-uploaded reference materials (PDFs, notes, web snippets). Start with Read tracks/<track>/materials/INDEX.md — the auto-generated listing shows every file with page count, ≈ token count, and status. For content, prefer Bash(sg-search "<topic>" --track <track> --k 8) to find the most relevant passages across all files; cite as [<filename>, p.<N>]. To zoom in, open materials/.text/<file>.md (page-anchored mirror) at the matching ## p. N. For image-pdf / pending / failed files, fall back to native Read(file.pdf, pages: "1-N") (≤20 pages per call). Don't try pdftotext via Bash. If materials conflict with your priors, materials win. Full retrieval reference: skills/_shared/materials.md.

Output

Create exactly one new lesson file at $STUDYGROUND_DIR/tracks/<current_track>/lessons/<NN>-<slug>.md, where NN is the next zero-padded index (start at 01 for a new track).

Lesson format

See _shared/lesson-format.md for the full spec. Highlights:

• Frontmatter with title, track, index, prereqs
• H2 sections; never deeper than H3
• Math with $...$ and $$...$$
• Code with fenced blocks; ```python run for in-browser executable, plain ```python for read-only
• Tables: real markdown pipe syntax (| col | col | with a --- separator row). NEVER a code fence containing space-aligned text — that renders as <pre>, not as a table, and ignores all table styling. Pipe tables get header underline, row separators, zebra, hover, and inline-code chips automatically.
• ?> markers: write the question AND a pre-written answer wrapped in <!-- answer:start --> … <!-- answer:end --> (1-4 sentences, matching the lesson's voice — longer only if the answer truly needs it). The reader folds these by default so the learner can pause and think before peeking.
• ?>> markers: write the question AND a short pre-answer wrapped in <details> with <summary>deeper</summary>. Keep btw answers 1–3 sentences.
• :::exercise <name> containers for hands-on practice (creates exercises/<name>/)

After writing

Update $STUDYGROUND_DIR/progress.json:

• If the track is new, add an entry
• Set current_track and tracks.<track>.current to this new lesson's slug

Keep the first lesson short (5–10 min read). Set up the mental model; don't try to cover everything.