Narrated demos and before-and-after video
The demo skills have your agent film your running app with a headless browser and turn it into a narrated demo video, with a voice-over timed to what is on screen. Each one lands in your Inbox, as Inbox, sharing and privacy explains.
The demo skills
record: a narrated demo of the change you just shipped.before_after: one half of a before and after pair. The agent records the bug before it touches the code, then the same path after the fix. Vidmatic pairs the two halves so they play back to back.demo_user_journey: a narrated demo of the shortest path a new user takes to a first win.
What your machine needs
Node and a headless browser. The skill installs Playwright itself if it is missing. Your app must be reachable from that machine; a local dev server is fine.
If your app needs a sign-in, a person captures it once with /mcp__vidmatic__record --init on a machine with a display. Later skills reuse it. See Skills.
How a narrated demo video is made
- The agent writes a script, one line per moment.
preflight_narrationchecks that each line fits its time slot. A line markedtightoroveris shortened before the agent records.- The agent records the screen to fit the script.
begin_uploaduploads the video.create_demoadds the script, and Vidmatic renders the voice-over.- The demo lands in your Inbox, and your agent prints the Inbox link Vidmatic returns.
Demos follow your account default in Settings → Demo videos: public unless you changed it, so the agent also prints a public link. Run a skill with --private (or --publish) to override it for one demo. Every demo lands in your Inbox either way.
Voices and script limits
| Voice | Voice id | Accent |
|---|---|---|
| Heart | af_heart | American, female |
| Bella | af_bella | American, female |
| Nicole | af_nicole | American, female |
| Adam | am_adam | American, male |
| Michael | am_michael | American, male |
| Emma | bf_emma | British, female |
| George | bm_george | British, male |
- Up to 200 lines per script, 1,000 characters per line, 20,000 characters in all.
- Up to 30 minutes of speech.
How a change was built
explain_implementation runs only when you ask for it. It makes a narrated explainer of a shipped issue or pull request: what was asked, the decisions, the code and the architecture. The video shows your code on screen; it stays in your Inbox unless you publish it.