pptx-generator

SKILL.md

PPTX Generator & Editor

Overview

This skill handles all PowerPoint tasks: reading/analyzing existing presentations, editing template-based decks via XML manipulation, and creating presentations from scratch using PptxGenJS. It includes a complete design system (color palettes, fonts, style recipes) and detailed guidance for every slide type.

Quick Reference

Task
Approach

Read/analyze content
python -m markitdown presentation.pptx

Edit or create from template
See Editing Presentations

Create from scratch
See Creating from Scratch below

Item
Value

Dimensions
10" x 5.625" (LAYOUT_16x9)

Colors
6-char hex without # (e.g., "FF0000")

English font
Arial (default), or approved alternatives

Chinese font
Microsoft YaHei

Page badge position
x: 9.3", y: 5.1"

Theme keys
primary, secondary, accent, light, bg

Shapes
RECTANGLE, OVAL, LINE, ROUNDED_RECTANGLE

Charts
BAR, LINE, PIE, DOUGHNUT, SCATTER, BUBBLE, RADAR

Reference Files

File
Contents

slide-types.md
5 slide page types (Cover, TOC, Section Divider, Content, Summary) + additional layout patterns

design-system.md
Color palettes, font reference, style recipes (Sharp/Soft/Rounded/Pill), typography & spacing

editing.md
Template-based editing workflow, XML manipulation, formatting rules, common pitfalls

pitfalls.md
QA process, common mistakes, critical PptxGenJS pitfalls

pptxgenjs.md
Complete PptxGenJS API reference

Reading Content

# Text extraction
python -m markitdown presentation.pptx

Creating from Scratch — Workflow

Use when no template or reference presentation is available.

Step 1: Research & Requirements

Search to understand user requirements — topic, audience, purpose, tone, content depth.

Step 2: Select Color Palette & Fonts

Use the Color Palette Reference to select a palette matching the topic and audience. Use the Font Reference to choose a font pairing.

Step 3: Select Design Style

Use the Style Recipes to choose a visual style (Sharp, Soft, Rounded, or Pill) matching the presentation tone.

Step 4: Plan Slide Outline

Classify every slide as exactly one of the 5 page types. Plan the content and layout for each slide. Ensure visual variety — do NOT repeat the same layout across slides.

Step 5: Generate Slide JS Files

Create one JS file per slide in slides/ directory. Each file must export a synchronous createSlide(pres, theme) function. Follow the Slide Output Format and the type-specific guidance in slide-types.md. Generate up to 5 slides concurrently using subagents if available.

Tell each subagent:

File naming: slides/slide-01.js, slides/slide-02.js, etc.

Images go in: slides/imgs/

Final PPTX goes in: slides/output/

Dimensions: 10" x 5.625" (LAYOUT_16x9)

Fonts: Chinese = Microsoft YaHei, English = Arial (or approved alternative)

Colors: 6-char hex without # (e.g. "FF0000")

Must use the theme object contract (see Theme Object Contract)

Must follow the PptxGenJS API reference

Step 6: Compile into Final PPTX

Create slides/compile.js to combine all slide modules:

// slides/compile.js
const pptxgen = require('pptxgenjs');
const pres = new pptxgen();
pres.layout = 'LAYOUT_16x9';

const theme = {
  primary: "22223b",    // dark color for backgrounds/text
  secondary: "4a4e69",  // secondary accent
  accent: "9a8c98",     // highlight color
  light: "c9ada7",      // light accent
  bg: "f2e9e4"          // background color
};

for (let i = 1; i <= 12; i++) {  // adjust count as needed
  const num = String(i).padStart(2, '0');
  const slideModule = require(`./slide-${num}.js`);
  slideModule.createSlide(pres, theme);
}

pres.writeFile({ fileName: './output/presentation.pptx' });

Run with: cd slides && node compile.js

Step 7: QA (Required)

See QA Process.

Output Structure

slides/
├── slide-01.js          # Slide modules
├── slide-02.js
├── ...
├── imgs/                # Images used in slides
└── output/              # Final artifacts
    └── presentation.pptx

Slide Output Format

Each slide is a complete, runnable JS file:

// slide-01.js
const pptxgen = require("pptxgenjs");

const slideConfig = {
  type: 'cover',
  index: 1,
  title: 'Presentation Title'
};

// MUST be synchronous (not async)
function createSlide(pres, theme) {
  const slide = pres.addSlide();
  slide.background = { color: theme.bg };

  slide.addText(slideConfig.title, {
    x: 0.5, y: 2, w: 9, h: 1.2,
    fontSize: 48, fontFace: "Arial",
    color: theme.primary, bold: true, align: "center"
  });

  return slide;
}

// Standalone preview - use slide-specific filename
if (require.main === module) {
  const pres = new pptxgen();
  pres.layout = 'LAYOUT_16x9';
  const theme = {
    primary: "22223b",
    secondary: "4a4e69",
    accent: "9a8c98",
    light: "c9ada7",
    bg: "f2e9e4"
  };
  createSlide(pres, theme);
  pres.writeFile({ fileName: "slide-01-preview.pptx" });
}

module.exports = { createSlide, slideConfig };

Theme Object Contract (MANDATORY)

The compile script passes a theme object with these exact keys:

Key
Purpose
Example

theme.primary
Darkest color, titles
"22223b"

theme.secondary
Dark accent, body text
"4a4e69"

theme.accent
Mid-tone accent
"9a8c98"

theme.light
Light accent
"c9ada7"

theme.bg
Background color
"f2e9e4"

NEVER use other key names like background, text, muted, darkest, lightest.

Page Number Badge (REQUIRED)

All slides except Cover Page MUST include a page number badge in the bottom-right corner.

Position: x: 9.3", y: 5.1"

Show current number only (e.g. 3 or 03), NOT "3/12"

Use palette colors, keep subtle

Circle Badge (Default)

slide.addShape(pres.shapes.OVAL, {
  x: 9.3, y: 5.1, w: 0.4, h: 0.4,
  fill: { color: theme.accent }
});
slide.addText("3", {
  x: 9.3, y: 5.1, w: 0.4, h: 0.4,
  fontSize: 12, fontFace: "Arial",
  color: "FFFFFF", bold: true,
  align: "center", valign: "middle"
});

Pill Badge

slide.addShape(pres.shapes.ROUNDED_RECTANGLE, {
  x: 9.1, y: 5.15, w: 0.6, h: 0.35,
  fill: { color: theme.accent },
  rectRadius: 0.15
});
slide.addText("03", {
  x: 9.1, y: 5.15, w: 0.6, h: 0.35,
  fontSize: 11, fontFace: "Arial",
  color: "FFFFFF", bold: true,
  align: "center", valign: "middle"
});

Dependencies

pip install "markitdown[pptx]" — text extraction

npm install -g pptxgenjs — creating from scratch

npm install -g react-icons react react-dom sharp — icons (optional)