Generate Slides — Native PPTX engine for Open WebUI

Part of NEURA Office: native Word, PowerPoint and Excel for Open WebUI.

A Open WebUI Tool that generates native PowerPoint (.pptx) presentations from a JSON spec produced by the model. It doesn't export HTML or images: it builds the slides directly with python-pptx, with a coherent visual system, layered decorative shapes, native charts, icons inside circles and rich layouts.

The resulting file is saved through Open WebUI's Files API (with a /cache/files fallback) and a clickable download link appears in the chat.

License: MIT · Author: IANUSTEC

Slides generated from the example examples/deck.json → examples/demo_tech_deck.pptx.

Features

• Native, editable .pptx (text, charts and shapes are editable in PowerPoint/Keynote/LibreOffice).
• Native Office charts: bar, line, area, pie, doughnut, radar, stacked_bar.
• ~25 ready-made layouts: cover, sections, bullets, columns/comparison, KPIs, timeline, process flow, icon lists, icon grids, pillars, quote, alert, tables, diagrams (funnel, pyramid, cycle, quadrant, bullseye) and image layouts.
• Curated themes + custom accent (theme:"auto" infers the theme from the content).
• Lucide-style icons bundled in the file (no network dependency for icons).
• Optional images from Unsplash (with a key) or generated via Open WebUI.
• Single-file: one self-contained .py, ready to paste into the Tools registry.

Requirements

• Open WebUI >= 0.4.0
• Python: python-pptx, pillow (declared in the frontmatter → Open WebUI installs them automatically)
• Optional: httpx (fetch images from URL/Unsplash)

Installation

Option A — from the Open WebUI community

1. Open the tool page on the Open WebUI community site.
2. Click Get / Import to your instance.

Option B — manual

1. In your Open WebUI instance go to Workspace → Tools → +.
2. Paste the contents of generate_slides.py.
3. Save. The declared dependencies are installed on first use.
4. Enable the tool for the model (or chat) that should use it.

Usage

The model calls generate_slides(content), where content is a single JSON string. Minimal structure:

{
  "title": "Presentation title",
  "subtitle": "Optional subtitle",
  "author": "Author / company",
  "theme": "auto",
  "footer": "Footer label",
  "slides": [
    { "layout": "cover", "title": "...", "subtitle": "...", "icon": "cpu" },
    { "layout": "kpi_row", "title": "...", "stats": [ { "value": "-40%", "label": "..." } ] }
  ]
}

See the full example in examples/deck.json.

Themes

auto (default, inferred from content) · midnight · forest · ocean · coral · terracotta · teal · berry · sage · cherry · charcoal · slate. You can force the accent with "accent": "#C99A3B".

Available layouts (main fields)

Layout	Main fields
cover	title, subtitle, author, eyebrow, icon, date, chips[]
section	number ("01"), eyebrow, title, lead
title_bullets	title, eyebrow, bullets[]
title_body	title, eyebrow, body (paragraphs separated by \n)
two_column_text / comparison_two	left{}, right{} or columns[] (heading, icon, points[], highlight, badge)
kpi_row	stats[] with {value, label, change}
timeline_horizontal / process_flow	steps[] with {when, title, description}
icon_list_vertical	items[] with {icon, title, description}
icon_grid_2x2 / icon_grid_3 / pillars	items[] with {icon, title, description}
chart	chart_type, labels[], values[] or datasets[]{label,data[]}, insight[]
funnel / pyramid / cycle / quadrant / bullseye	nodes[] with {label, description}
quote	quote, author, role
alert	title, level (info|tip|warning|danger), body or bullets[]
table	headers[], rows[]
text_image_right / image_left_text_right	title, bullets[]/body, image_hint or image_url or base64
image_full_caption	title, subtitle, image_hint/image_url
closing	title, eyebrow, takeaways[], contact

Screenshots

Cover	KPI row
Native chart	Funnel

Valves (configuration)

Valve	Default	Description
default_theme	auto	Default theme when the spec doesn't set one
footer_label	""	Default footer (overridden by spec.footer)
unsplash_access_key	""	Unsplash key for stock images (optional)
image_generation	false	Enable AI image generation via Open WebUI
max_image_px	1600	Maximum image width
emit_status	true	Emit status events in chat
pptx_export_dir	/app/backend/data/cache/files	Fallback directory for saving

How it works

1. The model produces the JSON spec and calls generate_slides.
2. The engine resolves theme/accent, prefetches images (if any image layouts are present), and for each slide invokes the corresponding layout renderer.
3. Shapes, text and charts are written as native OOXML objects.
4. The .pptx is saved via the Files API (fallback /cache/files) and the link is returned in chat.

Local development / testing

Requires python-pptx and (optionally) pillow/httpx:

pip install python-pptx pillow httpx
python examples/build.py   # → examples/demo_tech_deck.pptx

The file is designed to run inside Open WebUI: the open_webui.* imports are optional and the tool degrades gracefully when they're missing (handy for isolated render tests).

Contributing

Issues and PRs welcome. Please keep the file single-file and free of mandatory network dependencies for the core features.

License

MIT © IANUSTEC