Skill: slide-generate

Generate a complete PowerPoint presentation from an analyzed template. The presentation will match the template's fonts, colors, layout patterns, and visual style.

Prerequisite: The template must be analyzed first using the slide-analyze skill.

Workflow

Step 1 — Accept Input

Gather from the user (ask if not provided):

• Topic: What the presentation is about
• Template name: Which analyzed template to use (list available templates in slide-workspace/templates/ if unsure)
• Slide count (optional): Desired number of slides (default: 8-10)

Step 2 — Verify Template Workspace

Check that the template workspace exists:

slide-workspace/templates/{template-name}/
  guideline.md     ← required
  sample_code.js   ← required
  images/          ← may be empty

If missing, inform the user to run slide-analyze on the template first.

Step 3 — Derive Presentation Name

Derive a filesystem-safe presentation name from the topic with a timestamp suffix:

• Replace spaces and special characters with hyphens
• Convert to lowercase
• Append a timestamp in YYYYMMDD-HHmmss format (use the current date/time)
• Example: "Q4 Sales Review 2024" → q4-sales-review-2024-20260407-143022

The timestamp ensures each run produces a unique folder so outputs are never overwritten.

Step 4 — Create Presentation Workspace

Create the presentation workspace directory:

slide-workspace/presentations/{presentation-name}/

Step 5 — Read Template Context

Read from the template workspace:

• guideline.md — design guidelines
• sample_code.js — primary reference: contains master definitions, layout patterns, background colors, image usage, and positioning examples
• List all files in images/ directory to get available image filenames

Step 6 — Generate Outline

Read prompt rules from shared/prompts/outline-rules.md.

Using the outline rules as system instructions and the template guideline + user's topic as context, generate a presentation outline:

• Numbered list of slide titles with bullet point content
• Match slide types from the template's Layout Patterns
• Include title/cover slide and thank-you/closing slide
• Keep to the requested slide count
• Each slide includes a Data section listing every chart, table, image, stat, or text element required on that slide (see outline-rules.md for exact format)

Save the outline to:

slide-workspace/presentations/{presentation-name}/outline.md

Step 7 — Extract Preamble from sample_code.js

Extract the preamble directly from sample_code.js — no LLM generation needed.

The preamble consists of everything in sample_code.js before the first slide block, which includes:

• const pptx = new PptxGenJS();
• pptx.defineLayout(...) (if present)
• All pptx.defineSlideMaster(...) calls
• Any top-level helper functions (e.g. function addLayout0Images(slide) {...})

A "slide block" begins when the first pptx.addSlide call appears. Stop extraction at that point.

Do NOT include any addSlide calls or pptx.writeFile(...).

Save the extracted section to:

slide-workspace/presentations/{presentation-name}/preamble.js

Step 8 — Generate Per-Slide Code

Parse the outline into individual slides (each numbered item is a slide).

Read prompt rules from shared/prompts/slide-code-rules.md.

For each slide in the outline:

• Use slide-code-rules.md as system instructions
• Provide: slide title + content, preamble.js for reference, guideline.md, sample_code.js (as style/pattern reference), available image filenames
• Generate code for ONE slide: let slide = pptx.addSlide('MASTER_X') + content
• Each slide starts with // Slide N: <title>
• Derive master name, background color, layout images, and positioning from sample_code.js patterns — do NOT use context.json

Collect all per-slide code blocks.

Step 9 — Combine into Final Script

Combine the code using this structure:

// Preamble
{preamble code}

// Hoisted helper functions (any `function name() {}` extracted from slide blocks)
{hoisted functions}

// Per-slide code (each wrapped in IIFE to prevent variable conflicts)
(function() {
  // Slide 1: ...
})();

(function() {
  // Slide 2: ...
})();

// ... more slides ...

pptx.writeFile({ fileName: 'output.pptx' });

Important — function hoisting: If any slide code defines top-level named functions (e.g., function addLayout0Images(slide) {...}), extract them from the slide block and place them before the IIFEs so they are accessible across all slides.

Save to:

slide-workspace/presentations/{presentation-name}/code.js

Step 10 — Check Dependencies

Check that pptxgenjs is available:

node -e "require('pptxgenjs')" 2>/dev/null

If it fails, run the setup script:

• Unix/macOS: bash shared/scripts/setup_deps.sh
• Windows: powershell -ExecutionPolicy Bypass -File shared/scripts/setup_deps.ps1

Step 11 — Run PPTXGenJS

Execute the code:

node shared/scripts/run_pptxgenjs.js \
  "slide-workspace/presentations/{presentation-name}/code.js" \
  "slide-workspace/templates/{template-name}/images" \
  "slide-workspace/presentations/{presentation-name}/output.pptx"

Step 12 — Report Result

Report to the user:

• Output file: slide-workspace/presentations/{presentation-name}/output.pptx
• Slide count generated
• Template used
• Any warnings from the runner

Output Structure

slide-workspace/
  presentations/
    {presentation-name}/
      outline.md      ← Presentation outline
      preamble.js     ← PptxGenJS init + slide master definitions
      code.js         ← Complete combined script
      output.pptx     ← Generated presentation file

Error Handling

• Template not found: Prompt user to run slide-analyze first
• Runner exits with code 3: JavaScript execution error — check code.js for syntax issues
• Runner exits with code 4: Script ran but no .pptx produced — check that pptx.writeFile() is called
• Output too large: Reduce slide count or simplify content

Notes

• The images variable is pre-injected by run_pptxgenjs.js as { filename: absolutePath } — never re-declare it in code.js
• context.json is NOT used during generation — all style/layout information is derived from sample_code.js and guideline.md
• The preamble is extracted verbatim from sample_code.js (not LLM-generated)
• Each slide MUST set slide.background matching the pattern in sample_code.js
• Layout helper functions (e.g., addLayout0Images) already defined in the preamble must be called as the FIRST statement on every slide
• Multiple slide masters must never be collapsed into one
• Helper functions must be hoisted to top level, outside IIFEs