Bundled Script Reference

Arguments, options, and usage for generate_slide_image.py, slides_to_pdf.py, validate_presentation.py, and pdf_to_images.py, plus the pptx-skill scripts and external tools this skill relies on.

Current runtime and API contracts

Reviewed 2026-09-30. Local tests use PyMuPDF 1.28.2, Pillow 12.3.0, python-pptx 1.0.2 and pypdf 6.19.0. Install packages in a dedicated environment; for a single command, for example:

uv run --isolated --with pymupdf==1.28.2 python scripts/pdf_to_images.py presentation.pdf review/slide --format png

Generation needs requests and OPENROUTER_API_KEY; it sends prompts and attached images to OpenRouter and the selected model provider. Prefer the environment or .env over putting a credential in shell history with --api-key.

• POST https://openrouter.ai/api/v1/images: Bearer authentication, JSON model, prompt, n: 1, aspect_ratio: "16:9", optional input_references containing image_url data URLs. The model is google/gemini-3.1-flash-image (Nano Banana 2). Its current endpoints accept up to 14 references, PNG/JPEG/GIF/WebP inputs, and no output_format capability; the helper checks returned PNG MIME/signature.
• Response: data[0].b64_json with optional media_type, rather than a chat message. Output filenames must end in .png. This does not promise vector/editable output, transparency, exact typography, or unchanged attached figures.
• POST https://openrouter.ai/api/v1/chat/completions: the review uses google/gemini-3.7-flash, multipart text plus image_url, and reads choices[0].message.content. Its 6.5/10 threshold is a local heuristic, not validation of scientific accuracy or accessibility.
• GET /api/v1/images/models and GET /api/v1/images/models/{model-id}/endpoints discover image capabilities; GET /api/v1/models verifies the review model's image input and text output. These public catalog responses have no page loop here.
• The helper makes one generation call and one review per draft, at most two drafts. A generation failure stops without replay; a failed refinement keeps the earlier draft. <stem>_review_log.json separates success (image saved), quality_met, final_reviewed, model IDs, and termination_reason. Missing reviews never invent scores.

Official sources: Image API, model endpoints, image inputs for review. The current contracts were checked against documentation/public catalogs and offline mock responses. No authenticated image/review request was made during this refresh.

Nano Banana 2 Script Reference

generate_slide_image.py

Generate presentation slides or visuals using Nano Banana 2 AI.

# Full slide (default) - generates complete slide as image
python scripts/generate_slide_image.py "slide description" -o output.png

# Visual only - generates just the image/figure for embedding in PPT
python scripts/generate_slide_image.py "visual description" -o output.png --visual-only

# With reference images attached (Nano Banana 2 will see these)
python scripts/generate_slide_image.py "Create a conceptual overview matching this style" -o slide.png --attach style_reference.png
python scripts/generate_slide_image.py "Draft a conceptual comparison of these designs" -o compare.png --attach concept_a.png --attach concept_b.png

Options:

• -o, --output: Output PNG path with .png suffix (required)
• --attach IMAGE: Attach image file(s) as context for generation (can use multiple times)
• --visual-only: Generate just the visual/figure, not a complete slide
• --iterations: Maximum drafts, 1 or 2 (default: 2)
• --api-key: OpenRouter API key (or set OPENROUTER_API_KEY env var)
• -v, --verbose: Verbose output

Attaching Reference Images:

Use --attach for conceptual context or style drafts. It may redraw every pixel, including labels, logos, axes and measurements. For final quantitative results, embed the original figure with native PowerPoint or Beamer geometry; do not ask the image model to combine or preserve it. Verify conceptual diagrams against the source before presenting them.

Environment Setup:

export OPENROUTER_API_KEY='your_api_key_here'
# Get key at: https://openrouter.ai/keys

slides_to_pdf.py

Combine multiple slide images into a single PDF.

# Combine PNG files
python scripts/slides_to_pdf.py slides/*.png -o presentation.pdf

# Combine specific files in order
python scripts/slides_to_pdf.py title.png intro.png methods.png -o talk.pdf

# From directory (sorted by filename)
python scripts/slides_to_pdf.py slides/ -o presentation.pdf

Options:

• -o, --output: Output PDF path (required)
• --dpi: PDF resolution (default: 150)
• -v, --verbose: Verbose output

Ordering: Explicit file arguments retain their given order. Each directory/glob expands in filename order; duplicates are removed at their first occurrence.

Tip: Name slides with numbers for correct ordering: 01_title.png, 02_intro.png, etc.

Tools and Scripts

Nano Banana 2 Scripts

generate_slide_image.py - Generate slides or visuals with AI:

# Full slide (for PDF workflow)
python scripts/generate_slide_image.py "Title: Introduction\nContent: Key points" -o slide.png

# Visual only (for PPT workflow)
python scripts/generate_slide_image.py "Diagram description" -o figure.png --visual-only

# Options:
# -o, --output       Output PNG path with `.png` suffix (required)
# --visual-only      Generate just the visual, not complete slide
# --iterations N     Maximum drafts, 1 or 2 (default: 2)
# -v, --verbose      Verbose output

slides_to_pdf.py - Combine slide images into PDF:

# From glob pattern
python scripts/slides_to_pdf.py slides/*.png -o presentation.pdf

# From directory (sorted by filename)
python scripts/slides_to_pdf.py slides/ -o presentation.pdf

# Options:
# -o, --output    Output PDF path (required)
# --dpi N         PDF resolution (default: 150)
# -v, --verbose   Verbose output

Validation Scripts

validate_presentation.py:

python scripts/validate_presentation.py presentation.pdf --duration 15

# Checks:
# - Slide count vs. recommended range
# - File size warnings
# - Slide dimensions
# - Font sizes (PowerPoint)
# - Compilation (Beamer)

pdf_to_images.py:

python scripts/pdf_to_images.py presentation.pdf output/slide --dpi 150

# Converts PDF to images for visual inspection
# Supports: JPG, PNG
# Adjustable DPI
# Page range selection

Validation limits and external PowerPoint tools

validate_presentation.py supports PDF, PPTX and TEX. Convert legacy PPT to PPTX/PDF first. It counts PDF pages (including Beamer overlays/appendices), not conceptual frames; its timing guidance is only a rehearsal aid. Font checks inspect explicit text-run sizes, not inherited theme sizes, tables, groups, reading order or text overflow. TEX validation runs one pdflatex -no-shell-escape pass; resolve citations and navigation with latexmk or the full bibliography build before delivery.

pdf_to_images.py uses the current pymupdf import and get_pixmap(dpi=...); --first/--last are inclusive and 1-based. Invalid ranges and nonpositive DPI fail. slides_to_pdf.py uses Pillow's save_all/append_images; DPI controls page dimensions, not new image detail. All input slides should share an aspect ratio and pixel size.

To review a PPTX deck, export it to PDF in PowerPoint or LibreOffice (soffice --headless --convert-to pdf deck.pptx) and use the bundled PDF renderer.

Sources: PyMuPDF rendering, Pillow PDF, python-pptx presentations, pypdf reader.

External Tools

Recommended:

• PDF viewer: For reviewing presentations
• Color contrast checker: WebAIM Contrast Checker
• Color blindness simulator: Coblis
• Timer app: For practice sessions
• Screen recorder: For self-review