New Diagram Skill for Claude

Create a New TikZ Diagram

Scaffold a diagram from templates/tikz-snippets/, check it against the prevention rules, compile standalone, run the reviewer with measurement citations, and loop until the diagram passes. Use this instead of writing TikZ from scratch; the snippets embed the invariants that tikz-prevention.md requires.

Inputs

• $0 (optional) — snippet name (without .tex). One of the filenames in templates/tikz-snippets/. If omitted, list the gallery and ask the user to pick.
• $1 (optional) — output path. Defaults to Figures/new_diagram.tex — ask the user if this target exists so we don't clobber.

Workflow

Step 1: Pick a snippet

ls -1 templates/tikz-snippets/*.tex

Current gallery (see templates/tikz-snippets/README.md for descriptions):

• dag-basic — 3-node causal DAG (X → Y with confounder U)
• dag-mediation — X → M → Y with direct path
• did-two-period — two-period difference-in-differences
• event-study — event-time coefficients with 95% CIs
• timeline — horizontal timeline with staggered events
• regression-scatter — scatter + OLS fit + confidence band
• flowchart-3step — vertical flow with decision diamond
• supply-demand — supply/demand with shifted demand

If $0 is not one of these, or is omitted, ask the user which to use.

Step 2: Copy the snippet to the output path

SRC="templates/tikz-snippets/$0.tex"
DST="${1:-Figures/new_diagram.tex}"

# Confirm before overwriting
if [ -f "$DST" ]; then
  echo "Output path already exists: $DST"
  # Ask the user whether to overwrite. Do NOT clobber silently.
fi

mkdir -p "$(dirname "$DST")"
cp "$SRC" "$DST"

Step 3: Edit the content to fit the user's intent

Ask the user what the diagram should show. Edit $DST with the Edit tool:

• Update the comment block at the top so the intent sentence matches the user's goal.
• Update the coordinate map comment if coordinates change.
• Rename nodes and edit labels. Keep node style (dag-node, flow-node, etc.) unless the meaning actually changes.
• Do not add a bare scale=X to the tikzpicture options. Coordinates shrink, text does not — collisions follow. Allowed forms: scale=X, every node/.style={scale=X} or scale=X, transform shape. See tikz-prevention.md P3 for the full rule and tikz-visual-quality.md for the scale=1.1 convention.
• Every new edge label must carry a directional keyword (above, below, left, right, above left, etc.). midway alone is a path position, not a direction — P4 violation.

Step 4: Prevention pre-check (MANDATORY)

Run the same shared Python checker /extract-tikz uses — this is the one tool that enforces both P3 and P4 consistently across the two skills:

python3 scripts/check-tikz-prevention.py "$DST"

• Exit 0 → passed, continue.
• Exit 1 → violations (stderr reports line, rule, snippet). Fix $DST and re-run until zero.
• Exit 2 → usage error (missing file etc.).

Do NOT re-implement the grep inline. The Python checker correctly handles multi-line \begin{tikzpicture}[...] options and multi-line \draw ... node {...} spans that a line-oriented grep cannot see.

Step 5: Standalone compile

All snippets are \documentclass[border=4pt]{standalone} so they compile without a Beamer frame and without Preambles/header.tex:

cd "$(dirname "$DST")"
xelatex -interaction=nonstopmode "$(basename "$DST")" > /tmp/tikz-compile.log 2>&1

Check exit code and *.pdf file size. If compile fails, read /tmp/tikz-compile.log and fix the .tex source.

Step 6: Visual review via tikz-reviewer

Spawn the tikz-reviewer agent with Task (subagent_type=tikz-reviewer). Pass the .tex source and the compiled .pdf path. The reviewer is now required to cite the pass and formula from tikz-measurement.md for every CRITICAL/MAJOR finding — vague reports are rejected.

Loop:

• If APPROVED → go to Step 7.
• If NEEDS REVISION or REJECTED → apply fixes to $DST, re-run Step 4 (prevention pre-check), re-compile (Step 5), re-invoke reviewer.

Max 5 rounds. If after 5 rounds the reviewer is still reporting CRITICAL issues, surface the situation to the user — the snippet or the requested content may need redesign, not just tweaking.

Step 7: Optional — convert to SVG for Quarto

If the user plans to use the diagram in Quarto slides (not just Beamer), convert the compiled PDF to SVG:

pdf2svg "${DST%.tex}.pdf" "${DST%.tex}.svg" 1

Snippet-based diagrams are single-page, so a single .svg with the same basename as .tex is correct here. This differs from /extract-tikz, which produces a multi-page PDF from a Figures/LectureN/extract_tikz.tex master and names outputs tikz_exact_00.svg, tikz_exact_01.svg, ... (0-based filenames over 1-indexed PDF pages). If you need multi-page output for slide-by-slide reveals, use /extract-tikz instead.

Step 8: Clean up build artifacts

cd "$(dirname "$DST")"
rm -f *.aux *.log *.out *.synctex.gz

Leave the .pdf and .svg (if generated). They're what downstream tools use.

Step 9: Report

Print a summary:

• Snippet used → output path
• Reviewer verdict and number of rounds
• .pdf size and page count
• .svg path if generated
• Reminder to \input or \includegraphics the diagram in the target Beamer/Quarto file

Why start from a snippet?

Writing TikZ from scratch reliably produces collisions because the author cannot visually estimate where curves and labels will land. The snippets embed the invariants that tikz-prevention.md requires — coordinate maps, explicit node dimensions, directional edge labels — so the diagram passes the prevention pre-check by construction. You can always deviate from the snippet; the rules still apply.

Cross-references

• .claude/rules/tikz-prevention.md — the P1–P6 authoring rules.
• .claude/rules/tikz-measurement.md — the six-pass protocol with formulas the reviewer cites.
• .claude/rules/tikz-visual-quality.md — general visual standards.
• .claude/skills/extract-tikz/SKILL.md — for pulling TikZ out of an existing Beamer deck instead of creating new.
• templates/tikz-snippets/README.md — gallery inventory and adaptation guide.