Presentation creation, editing, and analysis. When Claude needs to work with presentations (.pptx files) for: (1) Creating new presentations, (2) Modifying or editing content, (3) Working with layouts, (4) Adding comments or speaker notes, or any other presentation tasks
npxskills add guanyang/antigravity-skills--skill pptxLoading…
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 |
Paths are relative to this skill's directory. Everything else is plain Python, , or shell.
node| 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 |
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:
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".)#, 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.shadow/options object across two add* calls — build a fresh object each time.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.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).new pptxgen() per output file — never reuse an instance.rectRadius only works on ROUNDED_RECTANGLE, not RECTANGLE.margin: 0 whenever text must align with a shape, line, or icon at the same x.slide.addNotes("...") (plain text, once per slide), never in a text box on the slide.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.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).dataLabelPosition must be ctr, inEnd, or inBase. outEnd corrupts the file.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.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.<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.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).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; 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.
python3 -c "import sys,zipfile; zipfile.ZipFile(sys.argv[1]).extractall('unpacked')" deck.pptx
python scripts/add_slide.py unpacked/ slide2.xml --after slide2.xml # duplicate a slide (or slideLayoutN.xml); prints the new slide's path
# reorder / delete slides = edit <p:sldIdLst> in ppt/presentation.xml
python scripts/clean.py unpacked/ # after deletions: removes orphaned slides, media, rels
# edit slide content in ppt/slides/slideN.xml
(cd unpacked && rm -f ../out.pptx && zip -Xr ../out.pptx .) # zip from INSIDE the dir; rm first or deleted parts survive
python scripts/office/validate.py out.pptx --original deck.pptx
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.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.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)..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.When filling in a template:
defusedxml.minidom — round-tripping OOXML through xml.etree.ElementTree rewrites namespace prefixes and corrupts the deck.<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:).<a:buChar>, <a:buAutoNum> (numbered), or <a:buNone> to override — never a literal • in the text.xml:space="preserve" on its <a:t>.Don't create boring slides. Plain bullets on a white background won't impress anyone. Consider ideas from this list for each slide.
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) |
Every slide needs a visual element — image, chart, icon, or shape. Text-only slides are forgettable.
Layout options:
Data display:
Visual polish:
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:
| Element | Size |
|---|---|
| Slide title | 36-44pt bold |
| Section header | 20-24pt bold |
| Body text | 14-16pt |
| Captions | 10-12pt muted |
margin: 0 on the text box or offset the shape to account for paddingFFFFFF) or the user's brand palette; avoid warm-neutral defaults like F5F5DC, FAF0E6, FAEBD7, FFF8E1Your first render usually has a few real issues — overlaps, overflow, misalignment. Find and fix those, re-render only the slides you changed, and stop.
markitdown output.pptx
Check for missing content, typos, wrong order.
When using templates, check for leftover placeholder text:
markitdown output.pptx | grep -iE "\bx{3,}\b|lorem|ipsum|\bTODO|\[insert|this.*(page|slide).*layout"
If grep returns results, fix them before declaring success.
python scripts/office/validate.py output.pptx # built from scratch
python scripts/office/validate.py output.pptx --original src.pptx # built from a template
If the deck came from a template, always pass --original. A template may itself
contain parts the XSD rejects, so a bare run can report failures you never caused — and
a genuine regression can hide among them. --original baselines
the schema and slide checks against the template, suppressing errors it already had.
The structural checks — relationships, content types, charts — ignore --original and
report template-inherited problems either way, so read those on their own merits.
pptxgenjs emits chart XML PowerPoint refuses to open, and every other tool accepts: python-pptx opens those decks, LibreOffice renders them, the XSD passes them. Every failure names its fix. Fix it in the generator and rebuild.
Convert the slides to images (see Converting to Images) and inspect every one. After staring at the generating code you tend to see what you expect rather than what rendered, so look at the images fresh (a subagent works well for this if you have one). User-visible defects to look for:
Convert presentations to individual slide images for visual inspection:
python scripts/office/soffice.py --headless --convert-to pdf output.pptx
rm -f slide-*.jpg
pdftoppm -jpeg -r 150 output.pdf slide
ls -1 "$PWD"/slide-*.jpg
Pass the absolute paths printed above directly to the view tool. The rm clears stale images from prior runs. pdftoppm zero-pads based on page count: slide-1.jpg for decks under 10 pages, slide-01.jpg for 10-99, slide-001.jpg for 100+.
After fixes, rerun all four commands above — the PDF must be regenerated from the edited .pptx before pdftoppm can reflect your changes.
pptxgenjs (npm, preinstalled — install only if require('pptxgenjs') fails) · markitdown[pptx], Pillow, defusedxml, lxml (pip — text dump, thumbnail, clean, validate) · LibreOffice (soffice, auto-configured for sandboxed environments via scripts/office/soffice.py) · pdftoppm (Poppler)
Create or update AgentSkills. Use when designing, structuring, or packaging skills with scripts, references, and assets.
Create or update AgentSkills. Use when designing, structuring, or packaging skills with scripts, references, and assets.
Set up and use 1Password CLI (op). Use when installing the CLI, enabling desktop app integration, signing in (single or multi-account), or reading/injecting/running secrets via op.
CLI to manage emails via IMAP/SMTP. Use `himalaya` to list, read, write, reply, forward, search, and organize emails from the terminal. Supports multiple accounts and message composition with MML (MIME Meta Language).
Create or update AgentSkills. Use when designing, structuring, or packaging skills with scripts, references, and assets.
Create or update AgentSkills. Use when designing, structuring, or packaging skills with scripts, references, and assets.
Set up and use 1Password CLI (op). Use when installing the CLI, enabling desktop app integration, signing in (single or multi-account), or reading/injecting/running secrets via op.
CLI to manage emails via IMAP/SMTP. Use `himalaya` to list, read, write, reply, forward, search, and organize emails from the terminal. Supports multiple accounts and message composition with MML (MIME Meta Language).