demo:capture

Demo Capture (Playwright MCP)

Capture a narrated demo video that proves features work, not just shows screens where features live.

Input

You MUST receive a complete markdown demo script. Do not invent or improvise a demo — if no script is provided, ask the caller for one.

Demo Script Format

The script must contain these sections:

• # Demo: <title> — title, used in the output filename
• **Start:** <url> — URL where the demo begins
• **Auth:** yes|no — whether authenticated session is needed (default: yes). Auth is handled automatically by the Playwright MCP server.
• ## Steps — ordered list where each item has:
  • Bold heading = narration text (burned into video overlay)
  • Body text = action description for the executor
  • _Prove:_ = what the frame must demonstrate to pass (REQUIRED)
  • _Fail if:_ = conditions that mean the frame failed its purpose (REQUIRED)
• ## Scrutiny (optional) — items to actively investigate. These make demos critical rather than superficial.

Script Validation (Before Execution)

The caller is responsible for validating the script before dispatching. For each step, the caller must verify:

1. The _Prove:_ criterion is achievable with the current app state and data
2. The navigation path will reach a page state that satisfies the proof
3. Seed data or existing documents contain the necessary content

Example of a bad script step (caught by validation):

3. **Word-level diff highlighting**
   Open Compare to Original on the blog post document.
   _Prove:_ Colored spans within a line show which words changed
   _Fail if:_ All changes are pure additions with no modified lines

If the document was created from empty, Compare to Original will only show additions. The caller should check this before writing the step — navigate to the page, inspect the data, and choose a path that exercises the feature (e.g., Version History diffs between intermediate versions where text was modified).