Saurav Panda
71cb1f3581
Long agent sessions on 2× displays bust the 2000px-per-side limit some image-aware LLMs enforce — a 2296×1143 CSS viewport produces a 4592×2286 PNG. Passing max_dim=1800 downscales the file before save (only when the image actually exceeds max_dim), keeping callers that don't pass it unchanged.
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Screenshots
capture_screenshot() writes a PNG of the current viewport. The file is in device pixels — on a 2× display a 2296×1143 CSS viewport produces a 4592×2286 PNG.
That matters for two reasons:
-
Click coordinates are CSS pixels. Don't read a target off the image and pass it to
click_at_xy()directly without dividing bydevicePixelRatio. The simplest workflow is to take the screenshot, look at it in a viewer that shows CSS coordinates, or measure relative positions and usejs("window.devicePixelRatio")to convert. -
Some LLMs reject images > 2000 px per side. Long sessions on 2× displays will eventually hit this. Pass
max_dim=1800to downscale the file before it gets into the conversation:
capture_screenshot("/tmp/shot.png", max_dim=1800)
The downscale only happens when the image actually exceeds max_dim, so it's safe to leave on for every shot.
Use full-page screenshots (full=True) only when you need to see content below the fold — they are much larger and slower than viewport-only.