Demo script — GIF recording¶

The README hero GIF is produced from a deterministic pretty trace in examples/pretty_demo.py — no API key, no network, no flaky timing. Re-record whenever the CLI pretty output changes.

Prep¶

# Install the recorder + converter (one-time):
uv tool install asciinema
cargo install --git https://github.com/asciinema/agg --tag v1.5.0

# Short prompt so the recording is clean:
export PS1='$ '
clear

Record¶

cd <repo-root>
rm -f demo/looplet_pretty.cast demo/looplet_pretty.gif
asciinema rec demo/looplet_pretty.cast --overwrite --cols 88 --rows 24 \
  --command "uv run --quiet --active python -m looplet.examples.pretty_demo"
agg demo/looplet_pretty.cast demo/looplet_pretty.gif --theme monokai \
  --cols 88 --rows 24 --font-size 15 --fps-cap 12 --idle-time-limit 1 \
  --last-frame-duration 2

Output: a short, deterministic GIF that shows the same append-only pretty printer used by looplet new --pretty and looplet run-workspace --pretty.

Docs Loop Demo¶

docs/demo.gif is a separate deterministic loop demo. It shows a real composable_loop(...) run with a mock LLM, an approval prompt, and Step.pretty() output.

cd <repo-root>
rm -f docs/demo.cast docs/demo.gif
asciinema rec docs/demo.cast --overwrite --cols 90 --rows 22 \
    --command "uv run --quiet --active python -m looplet.examples.scripted_demo"
agg docs/demo.cast docs/demo.gif --theme monokai --cols 90 --rows 22 --font-size 18

Output: ~5-second, 16-frame, ~40 KB GIF that loops forever. Shows a DebugHook printing per-dispatch/per-result lines, an ApprovalHook pause on the destructive delete_rows call, and a clean resume.

Real-LLM version (optional)¶

If you want a recording that hits a real model (Groq, Together, vLLM, Ollama), substitute the command:

asciinema rec docs/demo.cast --overwrite --cols 100 --rows 16 \
    --command "python -m looplet.examples.coding_agent 'write fizzbuzz in fizz.py and test it'"

Requires OPENAI_BASE_URL, OPENAI_MODEL, OPENAI_API_KEY and a fast (< 2 s/step) model. Timings won't be deterministic — expect slight variation between runs.

Re-record checklist¶

Fresh working directory (no leftover fizz.py, test_fizz.py).
The $ prompt is the only thing before the command.
No stderr warnings leaked into the tape (check with grep -i warn docs/demo.cast).
GIF is compact enough for README use and loops smoothly.
Frame count roughly matches lines of output (use Pillow to inspect if curious).