Screenshotting Neovim in the web container

Applies only to Claude Code on the web. CLAUDE_CODE_REMOTE must be true; the script refuses to run otherwise and that refusal is correct, not an obstacle to work around. If you are on a local machine, stop and say so — the user can see their own editor, and starting a hidden second Neovim to photograph it helps nobody.

The sequence

S=scripts/screenshot
$S/capture.sh start --cols 150 --rows 40 lua/vibing/core/utils/git_snapshot.lua
$S/capture.sh keys ':VibingChat right' Enter
$S/capture.sh shoot /tmp/shot.png
python3 $S/pxbox.py /tmp/shot.png --expect-height 798   # (rows - 2) * 21
$S/capture.sh stop

Then hand the PNG to the user with SendUserFile.

capture.sh shoot prints the exact pxbox.py command to run. Run it. A capture whose bottom rows were clipped is a plausible-looking screenshot of a slightly different screen, and the difference between 21px and 1px of painted height does not survive downscaling — you will not catch it by looking, and you will describe a statusline that is not in the image. pxbox.py exits non-zero when the painted region is short.

scripts/screenshot/README.md has the mechanism, the headless_shell trap, and why each terminal cell is its own element. Read it if something renders wrong.

Do not fabricate the contents

capture-pane returns the actual screen buffer, which is the whole point: the frontmatter, statusline path and highlighting in the image are Neovim's own output. Two ways to throw that away, both of which produce an image that lies:

• Writing a transcript into the chat buffer to make it look busy. Text you typed is not the renderer's output. If a screenshot needs a real assistant turn — tool headers, ### Modified Files, streaming — that costs real tokens, so ask first and say that is what the image shows.
• Describing what the screenshot shows without reading it back. Open the PNG and look before you narrate it.

Typing an unsent ## User message is fine and authentic — that is a real editor state a user reaches by typing.

Housekeeping

start writes a chat into the project's real .vibing/chat/, which is git-ignored, so nothing lands in a commit. Still run git status before committing, and capture.sh stop when done — a forgotten session keeps a Neovim alive for the rest of the container's life.