name	marimo-screenshot
description	Capture rendered marimo notebook output as a screenshot for analysis

Marimo Screenshot

Capture a marimo notebook's rendered output (charts, tables, markdown) as a PNG screenshot that Claude can view and analyze.

When the user wants you to see notebook output, or when you need to analyze charts/visualizations in a marimo notebook.

Start the notebook in run mode (executes cells, serves rendered output):
```
uv run marimo run notebooks/<notebook>.py --port 2719 --headless &
```
Wait for server to start:
```
sleep 10
```

Take screenshot with JS render time (Altair/Vega charts need ~15s):

npx playwright screenshot --wait-for-timeout 15000 --full-page \
  "http://localhost:2719" /tmp/marimo_output.png

Read the screenshot using the Read tool:
```
Read /tmp/marimo_output.png
```
Kill the server when done:
```
pkill -f "marimo run.*2719"
```

Charts not appearing:

Cells must return their output (e.g., mo.vstack([chart]) as the last expression)
If inside if/else, ensure all branches return a value

Blank screenshot:

Port in use:

name	marimo-screenshot
description	Capture rendered marimo notebook output as a screenshot for analysis