Use this skill any time a .pptx or .potx file is involved in any way — as input, output, or both. This includes: creating slide decks, pitch decks, or presentations; reading, parsing, or extracting text from any .pptx or .potx file (even if the extracted content will be used elsewhere, like in an em

PPTX creation, editing, and analysis A .pptx is a ZIP archive of XML files. Choose your approach by task: Task Approach Create a new deck Write a pptxgenjs script — see gotchas below Edit an existing deck, or build from a template unzip → edit ppt/slides/slideN.xml → zip Read content markitdown deck.pptx (one block per slide under <! Slide number: N markers); visual grid: python scripts/thumbnail.py deck.pptx Scripts Paths are relative to this skill's directory. Everything else is plain Python, node , or shell. Script What it does scripts/thumbnail.py deck.pptx [prefix] Labeled grid of every slide, for picking template layouts. .pptx only. Pass prefix — it defaults to thumbnails , which overwrites the grids of any other deck done in the same directory scripts/add slide.py unpacked/ slide2.xml [ after slideN.xml] Duplicate a slide (or a slideLayoutN.xml ) with all the package bookkeeping. Also takes a .pptx directly with o out.pptx scripts/clean.py unpacked/ Delete slides, media, and rels no longer referenced. Run after <p:sldIdLst is final scripts/office/validate.py deck.pptx [ original src.pptx] Schema, relationship, content type, chart and slide checks; each failure names its fix. Pass original for any template derived deck — it baselines the schema checks against the template, so the template's own XSD errors don't read as yours scripts/office/soffice.py headless convert to pdf deck.pptx LibreOffice wrapper — bare soffice hangs in this sandbox Creating with pptxgenjs — gotchas pptxgenjs is preinstalled — do not run npm install first; write the script and require('pptxgenjs') directly. Only if that require fails: npm install pptxgenjs . The model knows the API; these are the footguns: Set pres.layout before adding slides. The default canvas is LAYOUT 16x9 = 10" × 5.625" , not 13.3" wide. Coordinates past the edge are written, not clamped — the shape just isn't on the slide. ( LAYOUT WIDE is 13.3" × 7.5".) Hex colors: never , never 8 digits. color: "FF0000" . Both " FF0000" and alpha baked into the hex ( "00000020" ) corrupt the file . For translucency: transparency: 0 100 on fills and images, opacity: 0.0 1.0 on shadows — each is silently ignored on the other. pptxgenjs mutates option objects in place (converts values to EMU on first use). Never share one shadow /options object across two add calls — build a fresh object each time. Shadow offset must be ≥ 0 — a negative offset corrupts the file. To cast a shadow upward, use angle: 270 with a positive offset. letterSpacing is silently ignored — the real option is charSpacing . Lists: bullet: true on each item, never a literal • (renders double bullets). Set breakLine: true on every array item except the last. Space bulleted paragraphs with paraSpaceAfter , not lineSpacing (huge gaps). One new pptxgen() per output file — never reuse an instance. rectRadius only works on ROUNDED RECTANGLE , not RECTANGLE . Gradient fills aren't supported — use a gradient image as the background instead. Text boxes have built in internal padding — set margin: 0 whenever text must align with a shape, line, or icon at the same x. Speaker notes go in slide.addNotes("...") (plain text, once per slide), never in a text box on the slide. Keep charts native. Use addChart() for everything PowerPoint can chart (pass an array of {type, data, options} for combos). For PowerPoint native features the library doesn't expose (trendlines, error bars), compute the extra series yourself or post process the generated OOXML — do not fall back to a rendered image. Only chart types PowerPoint has no native form for (Sankey, network, chord) go in as images. Default charts render bare — no title, no data labels, dated palette. Set showTitle + title , showValue: true + dataLabelPosition , chartColors: [...] from your palette, and quiet the frame ( catAxisLabelColor / valAxisLabelColor , valGridLine: { color, size } , catGridLine: { style: "none" } , showLegend: false for a single series). On a stacked bar or column chart, dataLabelPosition must be ctr , inEnd , or inBase . outEnd corrupts the file . A combo series using secondaryValAxis / secondaryCatAxis needs both valAxes and catAxes on the chart options, two entries each. Without them pptxgenjs writes axis ids it never declares, and PowerPoint discards that chart and reports the file as corrupt. Supplying only valAxes is not enough. After writeFile() , run python scripts/office/validate.py deck.pptx . It reports the two chart faults above and the slide XML defects PowerPoint refuses, and names the fix for each. Fix them in your generator, not by hand editing the packed XML. Never reorder the children of <p:presentation . pptxgenjs writes <p:notesMasterIdLst right after <p:sldIdLst and points both masters at one theme part. PowerPoint reads that happily — move the element and the same deck becomes unopenable. Icons: render react icons to SVG ( ReactDOMServer.renderToStaticMarkup ), rasterize with sharp at ≥256px, and insert via addImage({ data: "image/png;base64," + buf.toString("base64") }) — the image/png;base64, prefix is required ( react icons , react , react dom , and sharp are preinstalled — npm install react icons react react dom sharp only if a require fails). Editing existing decks and templates Pick layouts first: python scripts/thumbnail.py template.pptx template thumbs writes a labeled grid of every slide and prints the file(s) it created — template thumbs.jpg , split into template thumbs N.jpg past 12 slides. Always pass that second argument, named after the deck. It defaults to thumbnails , so two decks thumbnailed in one directory silently overwrite each other's grids — the first deck's are simply gone (template analysis only — visual QA needs the full resolution renders from [Converting to Images]( converting to images); it only accepts .pptx , so copy a .potx to a .pptx name first). Use it with markitdown to map each content section onto a template slide, and vary the layouts — don't put every section on the same title and bullets slide. Do all structural work — add, delete, reorder — before editing any slide's content. add slide.py copies a slide file verbatim, so duplicating after you edit clones the edited content; and clean.py deletes any slide missing from <p:sldIdLst , including one you just wrote. Never copy a slide file by hand — add slide.py does every registration a new slide needs and reports what it made ( Created ppt/slides/slide17.xml from slide2.xml ). It also works directly on a file: add slide.py deck.pptx slide2.xml o out.pptx — pass o , or it rewrites the input deck in place. A duplicated slide still references its source's chart/SmartArt/embedded object parts rather than cloning them, so editing one slide's chart changes the other's. If you use python pptx , three things it won't do: duplicate a slide (its only entry point is add slide(layout) ), preserve formatting through text frame.text = "..." (that collapses the paragraph to a single unstyled run — assign run.text instead), or read the SVG/EMF most template art uses ( add picture raises UnidentifiedImageError ). Legacy .ppt must be converted first: python scripts/office/soffice.py headless convert to pptx file.ppt . .potx templates unpack and pack identically — keep the .potx extension on the output. To reuse a template icon or image, duplicate a slide or layout that already contains it. When filling in a template: If you script an XML transform, parse with defusedxml.minidom — round tripping OOXML through xml.etree.ElementTree rewrites namespace prefixes and corrupts the deck. Template slots ≠ source items. If the template shows 4 team members and you have 3, delete the 4th member's entire group (image + text boxes), not just its text — then check for orphaned visuals in QA. One <a:p per list item — never concatenate items into a single paragraph. Copy the sibling <a:pPr to preserve spacing, and put b="1" on the <a:rPr of titles, section headers, and inline labels ( Status: , Owner: ). Let bullets inherit from the layout; only add <a:buChar , <a:buAutoNum (numbered), or <a:buNone to override — never a literal • in the text. Text with leading or trailing spaces needs xml:space="preserve" on its <a:t . Design Ideas Don't create boring slides. Plain bullets on a white background won't impress anyone. Consider ideas from this list for each slide. Before Starting Pick a bold, content informed color palette : The palette should feel designed for THIS topic. If swapping your colors into a completely different presentation would still "work," you haven't made specific enough choices. Dominance over equality : One color should dominate (60 70% visual weight), with 1 2 supporting tones and one sharp accent. Never give all colors equal weight. Dark/light contrast : Dark backgrounds for title + conclusion slides, light for content ("sandwich" structure). Or commit to dark throughout for a premium feel. Commit to a visual motif : Pick ONE distinctive element and repeat it — rounded image frames, icons in colored circles. Carry it across every slide. Do not use a color bar or accent stripe as your motif (see Avoid list). Color Palettes Choose colors that match your topic — don't default to generic blue. Use these palettes as inspiration: Theme Primary Secondary Accent Midnight Executive 1E2761 (navy) CADCFC (ice blue) FFFFFF (white) Forest & Moss 2C5F2D (forest) 97BC62 (moss) F5F5F5 (cream) Coral Energy F96167 (coral) F9E795 (gold) 2F3C7E (navy) Warm Terracotta B85042 (terracotta) E7E8D1 (sand) A7BEAE (sage) Ocean Gradient 065A82 (deep blue) 1C7293 (teal) 21295C (midnight) Charcoal Minimal 36454F (charcoal) F2F2F2 (off white) 212121 (black) Teal Trust 028090 (teal) 00A896 (seafoam) 02C39A (mint) Berry & Cream 6D2E46 (berry) A26769 (dusty rose) ECE2D0 (cream) Sage Calm 84B59F (sage) 69A297 (eucalyptus) 50808E (slate) Cherry Bold 990011 (cherry) FCF6F5 (off white) 2F3C7E (navy) For Each Slide Every slide needs a visual element — image, chart, icon, or shape. Text only slides are forgettable. Layout options: Two column (text left, illustration on right) Icon + text rows (icon in colored circle, bold header, description below) 2x2 or 2x3 grid (image on one side, grid of content blocks on other) Half bleed image (full left or right side) with content overlay Data display: Large stat callouts (big numbers 60 72pt with small labels below) Comparison columns (before/after, pros/cons, side by side options) Timeline or process flow (numbered steps, arrows) Visual polish: Icons in small colored circles next to section headers Italic accent text for key stats or taglines Typography Font names you write into the .pptx are rendered by the user's PowerPoint, not by this environment. Your visual QA renders via LibreOffice, which substitutes fonts it doesn't have — and for some fonts the substitute has different widths, so your QA preview can show text overflow (or fit) that the real deck won't have. To keep your QA trustworthy: Safe fonts (render true to width in QA and ship with Office): Arial, Calibri, Cambria, Times New Roman, Courier New, Bookman Old Style, Century Schoolbook . Use these for body text and anything where fit matters. Headers with personality at zero QA risk : pair a safe list serif header (Cambria, Bookman Old Style, Century Schoolbook) with a safe list sans