| name | loadshow-usage |
| description | Record a web page loading as an MP4 video and put two recordings side by side, using the loadshow CLI, with network and CPU throttling so the result resembles a real visit. Use when the user asks to show or visualise how slowly a page loads, wants a before/after video of a performance improvement, needs something to show a client or a non-technical stakeholder about page speed, or asks to record a page load. |
| license | MIT |
| compatibility | Requires the `loadshow` binary on PATH — run the loadshow-install skill if it is missing — and a Chrome or Chromium install for it to drive. On Linux, H.264 output additionally needs ffmpeg; AV1 does not. |
| allowed-tools | Bash(loadshow:*) Bash(command:*) Bash(ls:*) Read |
loadshow-usage
Page-load videos, and honest comparisons between them.
1. Confirm the tool
command -v loadshow && loadshow --version
Missing binary? Run the loadshow-install skill. It also needs Chrome or
Chromium; on Linux, H.264 encoding needs ffmpeg — --codec av1 avoids that
dependency.
2. A recording is not a measurement
This is the mistake that matters. The video shows one load, on this machine,
at this moment. It is a demonstration, not a metric.
- Never report a duration from a recording as the page's load time.
- Never compare two recordings taken with different settings.
- If the user wants numbers, say so and point at
crux or Lighthouse. If they
want something to show someone, this is the right tool.
3. Throttle, or the video is misleading
An unthrottled recording on a developer laptop makes almost any page look fast.
Set conditions explicitly and say what you used:
loadshow record https://example.com -o before.mp4 \
--preset mobile --download-mbps 10 --cpu-throttling 4
--preset is mobile (default) or desktop. --cpu-throttling 4 is roughly
a low-end phone. --download-mbps / --upload-mbps take 0 for unlimited.
4. For a before/after, pin every setting
loadshow record "$URL_BEFORE" -o before.mp4 --preset mobile --download-mbps 10 --cpu-throttling 4
loadshow record "$URL_AFTER" -o after.mp4 --preset mobile --download-mbps 10 --cpu-throttling 4
loadshow juxtapose before.mp4 after.mp4 -o comparison.mp4 --gap 8
Same preset, same viewport, same throttling, both times. juxtapose will
combine two videos regardless — it cannot tell you they were not comparable,
so that check is yours.
Recording takes real time: the page has to load, bounded by --timeout-sec
(default 30). A long encode is not a hang.
5. Read the reference for anything else
loadshow llm
loadshow record --help
6. Report from the summary, not from memory
loadshow record "$URL" -o out.mp4 --output-summary out.md
--output-summary writes a Markdown summary of the run. Quote that, state the
throttling you applied, and give the output path. Say that the video is a
demonstration under stated conditions — not a benchmark.
Failure modes
| Symptom | Fix |
|---|
command not found: loadshow | run the loadshow-install skill |
| Chrome not found | install Chrome/Chromium, or pass --chrome-path |
| timeout on a slow page | raise --timeout-sec |
| TLS error on staging | --ignore-https-errors |
| H.264 fails on Linux | install ffmpeg, pass --ffmpeg-path, or use --codec av1 |
| page looks unrealistically fast | no throttling — set --download-mbps and --cpu-throttling |
| no output file | --output / -o is required |
looked for go-loadshow | the command is loadshow; only the repository carries the go- prefix |
