Creating Presentations

PPTX Processing

.pptx is a ZIP archive of XML and resources. Choose workflow by intent.

Workflow Decision

| Intent | Workflow | Reference | |--------|----------|-----------| | Read text | markitdown → markdown | [thumbnails-and-conversion.md](references/thumbnails-and-conversion.md) | | Analyze layout / comments / theme | unpack → raw XML | [thumbnails-and-conversion.md](references/thumbnails-and-conversion.md) | | Create new from scratch | html2pptx | [html2pptx.md](html2pptx.md) + [design-patterns.md](references/design-patterns.md) | | Create using template | rearrange + inventory + replace | [template-workflow.md](references/template-workflow.md) | | Edit existing slides | unpack → OOXML → pack | [ooxml.md](ooxml.md) | | Visual review | thumbnail grids | [thumbnails-and-conversion.md](references/thumbnails-and-conversion.md) |

Iron Rules

• Color choice is design — see [palettes.md](references/palettes.md), state your approach BEFORE code.
• Web-safe fonts only — Arial, Helvetica, Times New Roman, Georgia, Courier New, Verdana, Tahoma, Trebuchet MS, Impact.
• Layout matches content count — 2 items → 2 columns; 3 → 3; never force.
• Validate visually — always generate thumbnails after creation, inspect for cutoff/overlap/contrast.

Create New (without template) — html2pptx

1. MANDATORY — READ ENTIRE FILE: html2pptx.md. NEVER set range limits.
2. Create HTML per slide (e.g., 720pt × 405pt for 16:9)

• Use `, –, , `
• class="placeholder" for chart/table areas (gray bg for visibility)
• CRITICAL: Rasterize gradients & icons as PNG via Sharp first, then reference in HTML
• Use full-slide or two-column layout for charts/tables — never vertical stack

1. Run scripts/html2pptx.js to convert

• html2pptx() per HTML file
• Charts/tables via PptxGenJS API on placeholders
• pptx.writeFile() to save

1. Visual validation — python scripts/thumbnail.py output.pptx workspace/thumbnails --cols 4

• Inspect for: text cutoff, overlap, positioning, contrast
• Adjust HTML margins/spacing/colors, regenerate, repeat

Create with Template

See [template-workflow.md](references/template-workflow.md) for full 7-step workflow (extract → inventory → outline → rearrange → inventory text → generate replacements → apply).

Edit Existing Presentation

1. MANDATORY — READ ENTIRE FILE: ooxml.md (~500 lines). NEVER set range limits.
2. python ooxml/scripts/unpack.py
3. Edit XML (primarily ppt/slides/slide{N}.xml)
4. CRITICAL — validate after each edit: python ooxml/scripts/validate.py --original
5. python ooxml/scripts/pack.py

Code Style

Concise code, no verbose names, no unnecessary print statements.

Dependencies

| Package | Install | Purpose | |---------|---------|---------| | markitdown | pip install "markitdown[pptx]" | Text extraction | | pptxgenjs | npm i -g pptxgenjs | Create via html2pptx | | playwright | npm i -g playwright | HTML rendering | | react-icons | npm i -g react-icons react react-dom | Icons | | sharp | npm i -g sharp | SVG rasterization | | LibreOffice | apt install libreoffice | PDF conversion | | Poppler | apt install poppler-utils | pdftoppm | | defusedxml | pip install defusedxml | Secure XML |

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: telagod
• Source: telagod/code-abyss
• License: MIT
• Homepage: https://www.npmjs.com/package/code-abyss

Install and usage instructions live in the source repository linked above.