#30400 Transcript: more room around notes between tool calls

Leo, 2026-11-01: "the thoughts in between tool calls probably want a bit more padding"

What changed

A short interim note the agent writes between two runs of calls is folded into the run as a quiet line (turns.ts mergeShortNotes, drawn as .cv-tool-note in TurnRows.tsx). It had 3px to the tool rows around it, so in an opened run it sat tight against "List …" above and "Ran 2 commands" below.

• .cv-tool-note now has --cv-note-gap above and below it: the 12px plain status gap (--cv-status-gap-plain, the transcript's inner gap in design/grid.md 5.5). That is the room a longer reply between two runs already has (cmux#29124), so a note and a reply between tool rows read the same.
• model.ts activityStepHeight estimates a note as its 20px line plus the gap on both sides, so estimated heights match drawn ones.
• Unchanged: the gaps between consecutive tool rows, the status rows between replies (12/12 from #29124), the icon column, subagent rows, prompts and final replies, colours and type.

Design: leo-workspace design/chat-transcript.md (rows between replies, grouped steps); the spec gets a "Notes between tool rows" entry in a follow-up leo-workspace PR.

Gallery

agent-pane.interim-prose-gap: a running turn's opened run (a command, a note, "Ran 2 commands" opened, a note, a command). Variants: shipped (12px), tight (before, 3px), snug (8px, the message gap), roomy (16px, the turn gap). I picked 12 because it is the same room a longer reply between two runs has, so the two kinds of interim prose stay consistent; 8 is barely more than the rows' own leading, and 16 is the turn gap, which would make a note read like a turn boundary inside one run.

Verification

cd webviews && CMUX_BROWSER_TESTS=1 bun test test/transcript-interim-prose-gap.test.ts (Chromium, light and dark), on the build fleet through cmux-ci test:

• Red at the test commit 65867b889e9b: each note had 3px above and below it (note -> Ran 2 commands: 3px, not 12px, and so on).
• Green at the fix: 12px on all four sides of the two notes, and every other gap in the run matches the tight variant.

Also on the fleet at the fix: rowEstimates.test.ts (21 pass), transcript-row-alignment.test.ts (2 pass, light and dark), and bun run check:pieces (lint, format, type check) clean.

Observed / Not run

• Observed: the fleet runs above.
• Not run: no native build or Mac capture; this is a webview CSS and estimate change.

Changelog

• Changed: Short notes between tool calls in the agent transcript have more room above and below them.

🤖 Generated with Claude Code

Agent session: agent session

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Summary by cubic

Short notes the agent writes between tool calls in the transcript now have 12px of room above and below them, matching the spacing a longer reply between two runs already has, instead of 3px.

• Updates the note's CSS margin to use the plain status gap (--cv-note-gap, 12px) and adds gallery variants comparing 3, 8, 12, and 16px.
• Updates activityStepHeight in model.ts to estimate a note as its 20px line plus the gap on both sides.
• Adds a browser test measuring the gaps around notes in light and dark themes.