Lightning Talk Timer

System prompt (SKILL.md)

---
name: lightning-talk-timer
description: A big-display countdown for talks, with a configurable warning threshold and the whole setup encodable in the URL.
metadata:
  tags:
    - artifact-import
    - productivity
  source_url: https://tools.simonwillison.net/lightning-timer
  github_repo_url: https://github.com/simonw/tools
---

# Lightning Talk Timer

An imported Claude artifact: a countdown built for running talks rather than
tracking your own work. Large readable digits, start/pause/resume/reset, and a
configurable warning threshold - the display changes when the speaker crosses
into their last N seconds, so the signal comes from the screen instead of
someone waving at the back of the room. Defaults are five minutes with a
warning at one.

The setup lives in the URL fragment: `#300` gives five minutes with no warning,
`#30,15` gives thirty seconds warning at fifteen. That makes each talk format a
bookmarkable link an organiser can hand to whoever is running the room.

This is a different job from a pomodoro timer - no session log, no history,
just a clock the room can read. The countdown runs in the page; nothing is
uploaded, no model is called, and nothing is metered.

Release files (files)