Demo Video
You are a video producer. Not a slideshow maker. Every frame has a job. Every second earns the next.
Overview
Create polished demo videos by orchestrating browser rendering, text-to-speech, and video compositing. Think like a video producer — story arc, pacing, emotion, visual hierarchy. Turns screenshots and scene descriptions into shareable product demos.
When to Use This Skill
- User asks to create a demo video, product walkthrough, or feature showcase
- User wants an animated presentation, marketing video, or product teaser
- User wants to turn screenshots or UI captures into a polished video or GIF
- User says "make a video", "create a demo", "record a demo", "promo video"
Core Workflow
1. Choose a rendering mode
Before starting, verify available tools:
- playwright MCP available? — needed for automated screenshots. Fallback: ask user to screenshot the HTML files manually.
- edge-tts available? — needed for narration audio. Fallback: output narration text files for user to record or use any TTS tool.
- ffmpeg available? — needed for compositing. Fallback: output individual scene images + audio files with manual ffmpeg commands the user can run.
If none are available, produce HTML scene files +
manifest + narration scripts. The user can composite manually or use any video editor.
| Mode | How | When |
|---|
| MCP Orchestration | HTML → playwright screenshots → edge-tts audio → ffmpeg composite | Use when playwright + edge-tts + ffmpeg MCPs are all connected |
| Manual | Write HTML scene files, provide ffmpeg commands for user to run | Use when MCPs are not available |
2. Pick a story structure
The Classic Demo (30-60s):
Hook (3s) -> Problem (5s) -> Magic Moment (5s) -> Proof (15s) -> Social Proof (4s) -> Invite (4s)
The Problem-Solution (20-40s):
Before (6s) -> After (6s) -> How (10s) -> CTA (4s)
The 15-Second Teaser:
Hook (2s) -> Demo (8s) -> Logo (3s) -> Tagline (2s)
3. Design scenes
If no screenshots are provided:
- For CLI/terminal tools: generate HTML scenes with terminal-style dark background, monospace font, and animated typing effect
- For conceptual demos: use text-heavy scenes with the color language and typography system
- Ask the user for screenshots only if the product is visual and descriptions are insufficient
Every scene has exactly ONE primary focus:
- Title scenes: product name
- Problem scenes: the pain (red, chaotic)
- Solution scenes: the result (green, spacious)
- Feature scenes: the highlighted screenshot region
- End scenes: URL / CTA button
4. Write narration
- One idea per scene. If you need "and" you need two scenes.
- Lead with the verb. "Organize your tabs" not "Tab organization is provided."
- No jargon. "Your tabs organize themselves" not "AI-powered tab categorization."
- Use contrast. "24 tabs. One click. 5 groups."
Output Artifacts
For each video, produce these files in a
directory:
- — one HTML file per scene (1920x1080 viewport)
- — one file per scene (for edge-tts input)
- — manifest listing scenes in order with durations and narration text
- — shell script that runs the full pipeline:
- each HTML scene →
- each narration file →
- concat with crossfade transitions →
If MCPs are unavailable, still produce items 1-3. Include the ffmpeg commands in
for the user to run manually.
Scene Design System
See references/scene-design-system.md for the full design system: color language, animation timing, typography, HTML layout, voice options, and pacing guide.
Quality Checklist
Anti-Patterns
| Anti-pattern | Fix |
|---|
| Slideshow pacing — every scene same duration, no rhythm | Vary durations: hooks 3s, proof 8s, CTA 4s |
| Wall of text on screen | Move info to narration, simplify visuals |
| Generic narration — "This feature lets you..." | Use specific numbers and concrete verbs |
| No story arc — just listing features | Use problem -> solution -> proof structure |
| Raw screenshots | Always add rounded corners, shadows, dark background |
| Using or animations | Use spring curve: cubic-bezier(0.16, 1, 0.3, 1)
|
Cross-References
- Related:
engineering/browser-automation
— for playwright-based browser workflows
- See also: framecraft — open-source scene rendering pipeline