PPTX Creation, Editing, and Analysis

A .pptx file is a ZIP archive of XML files. Choose your approach by task:

Task	Approach
Create a new deck	Write a pptxgenjs script
Edit an existing deck	unzip → edit XML → zip
Read content	markitdown deck.pptx

Creating with pptxgenjs

pptxgenjs is preinstalled — write the script and require('pptxgenjs') directly.

Critical Gotchas

• Set pres.layout before adding slides. Default is LAYOUT_16x9 = 10" × 5.625"
• Hex colors: never #, never 8 digits. Use "FF0000" format
• pptxgenjs mutates option objects in place — build fresh objects per call
• Shadow offset must be ≥ 0 — negative offsets corrupt the file
• letterSpacing is ignored; use charSpacing instead
• Lists: bullet: true on each item, breakLine: true on all but last
• Speaker notes go in slide.addNotes("...") (plain text)
• After writeFile(), run validation: python scripts/office/validate.py deck.pptx

const pptxgen = require('pptxgenjs');
const pres = new pptxgen();
pres.layout = 'LAYOUT_16x9';

const slide = pres.addSlide();
slide.addText('Hello World', {
  x: 0.5, y: 0.5, w: 9, h: 1,
  fontSize: 44, bold: true,
  color: '141413',
  fontFace: 'Poppins',
});

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

Editing Existing Decks

# Unpack
python3 -c "import sys,zipfile; zipfile.ZipFile(sys.argv[1]).extractall('unpacked')" deck.pptx

# Duplicate a slide
python scripts/add_slide.py unpacked/ slide2.xml --after slide2.xml

# Reorder/delete slides = edit <p:sldIdLst> in ppt/presentation.xml

# Clean orphans after deletion
python scripts/clean.py unpacked/

# Repack
(cd unpacked && rm -f ../out.pptx && zip -Xr ../out.pptx .)

# Validate
python scripts/office/validate.py out.pptx --original deck.pptx

Design Ideas

• Pick a bold, content-informed color palette
• One color dominates (60-70%), with 1-2 supporting tones and one accent
• Dark/light contrast for sandwich structure
• Commit to a visual motif — repeat it across every slide
• Every slide needs a visual element (image, chart, icon, shape)

Typography Safe Fonts

Arial, Calibri, Cambria, Times New Roman, Courier New

Element	Size
Slide title	36-44pt bold
Section header	20-24pt bold
Body text	14-16pt
Captions	10-12pt

Common Pitfalls

• ❌ Hex colors with # prefix — Corrupts the file
• ❌ Sharing option objects across add calls* — pptxgenjs mutates in place
• ❌ Text-only slides — Every slide needs a visual element
• ❌ Accent lines under titles — Hallmark of AI-generated slides
• ❌ Aptos font — Not available in all environments

Verification Checklist

• python scripts/office/validate.py output.pptx passes
• No placeholder text remains (grep for xxx, lorem, ipsum, TODO)
• Visual QA: no text overflow, no overlapping elements
• Charts render correctly with proper axis configuration
• Speaker notes are plain text (not text boxes)
• Colors use proper hex format (no #, no 8-digit)