[teamleaderleo]

Leo, 2026-11-01, on a column of transcript rows (tool rows, inbox lines, agent message lines, fold heads) whose vertical gaps differ by row type:

doesn't make sense for these to be spaced differently

Every one-line activity row in the agent transcript now draws on the tool rows' 22px line in a one-call tool run's frame (2px over, 4px under), and joins the step rows beside it, so any two consecutive one-line rows sit exactly 22px apart, top to top, whatever their kind. Their icons share one column and their words one text column.

Row (beside other one-line rows)	Height before	Pitch before	Height after	Pitch after
Tool row (one-call run)	22	28-34	22	22
Sent message line	26	34	22	22
Received / inbox line	26	28-38	22	22
Task notice line	22 (drawn at the row's right end)	28-34	22	22
Report batch head	22	28-38	22	22
Waiting group head	26 (icon 4px right, words 5.5px right)	38	22	22

What changed:

• model.ts: isLineRow names those rows (another agent's message, a notice, an inbox notice, a report batch, the waiting group). The estimator uses the same frame (LINE_ROW = 2 + 22 + 4) and an open group's member as its line alone.
• App.tsx: marks them acpmux-row--line and treats them as step rows, so they join their neighbours as tool runs already do.
• CSS: --cv-message-line is now the tool row height; received, pending and lane-batch lines drop their own vertical margins; the sent message's toggle is 22px and its hidden Copy no longer stretches the line to 24px; the waiting group's chevron and words sit on the shared icon and text columns; a task notice's tool line takes its row's width (it sat at the row's right end, since the row is a user row).
• Merged with Agent pane: status, tool and message rows and the action row line up with the prose #29124 (status rows centred between replies): a one-line row between two replies still takes its centred room; statusDelta counts its 4px run gap as a tool run's.
• model.ts also estimates a sent message (SendMessage, acpmux send, a sub-session's send_message) as one 22px line (review finding at 3bd8fe3).
• A received line's buttons take the line's 22px (DisclosureRow.css gave them a 26px floor).
• Design spec: leo-workspace design/chat-transcript.md, "One-line row pitch" (separate notes PR).

Prior art: #29754 (shared activity row grammar), #29613 (meta rows' icon and text columns) and #29124 (status rows' columns and centred gaps), all merged, are built on, not redone: this keeps their columns and adds the vertical rhythm. #29830 (flat waiting group) touches the group's contents, not its head geometry.

Changelog

Fixed: every one-line row in the agent transcript (tool rows, sent and received messages, inbox lines, background task lines, report and waiting-message fold heads) now sits on one line height and one spacing, with one icon and text column.

Test

CMUX_BROWSER_TESTS=1 bun test test/transcript-row-pitch-browser.test.ts (Chromium through cmux-ci test, real VirtualTranscript layout, light and dark): equal line height, equal top-to-top pitch, one icon x and one text x within 0.5px across 12 rows of 7 kinds.

• Red on base (commit d4488d8, run https://github.com/manaflow-ai/cmux/actions/runs/41264320120): t1 (cv-tool) is 22px tall, m1 26px, i1 sits 28px under t1, 38px elsewhere, t3 sits 34px under lane-notices:r1, n1 (cv-tool) icon at 534, 20 elsewhere, pending-messages icon at 24, 20 elsewhere; words at 48, 42.5 elsewhere, and more (19 findings).
• Review finding at f71b584 (a received line's buttons kept DisclosureRow's 26px floor inside the 22px line): the test now also checks that no part of a line stands out of it. Red at cce7be5 (run https://github.com/manaflow-ai/cmux/actions/runs/41275988869): m1 (cv-disclosure__line) has a part 2px out of its line, same for i1, i2, m2.
• Green at 00c42fe (run https://github.com/manaflow-ai/cmux/actions/runs/41276966512): 16 pass, 0 fail with transcript-meta-columns-browser, transcript-row-alignment (Agent pane: status, tool and message rows and the action row line up with the prose #29124's centred status gaps), incoming-message-disclosure-browser and received-message-fold-browser.

Observed / Not run

• Observed: the browser files above, plus at 8d0a643 (after the base merge) received-message-fold-browser, transcript-fold-no-blank-space-browser, other-session-message-actions-browser (all pass). Locally rowEstimates (a new case: a sent message estimates 2 + 22 + 4), agent-pane-reply-actions-frame, agent-pane-transcript-spacing, foldAnchor, footerActions pass; transcript-hover-fade fails on .cv-subagent__stop in subagents.css, a file this PR does not touch. Locally: rowEstimates, rowLayoutLinearity, continuationSpacing, lane-notice-batches, lane-notice-card, transcript-received-messages (41 pass). vp fmt / vp lint on the changed TS files, prepush-gate.py.
• Not run: the full webview suite (CI runs it), a DEV build by hand. No screenshots.

risk:normal

Agent session: agent session

🤖 Generated with Claude Code

[cubic-dev-ai]

3 issues found across 9 files

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. When an issue isn't valid or won't be fixed in this PR, reply in its thread with the reason and then resolve the thread. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="webviews/src/agent-session/acpmux/conversation/AgentMessageRow.css">

<violation number="1" location="webviews/src/agent-session/acpmux/conversation/AgentMessageRow.css:117">
P2: This custom property is not defined in the acpmux production entry, so the declaration is dropped and message toggles lose their row height there. Add a local fallback (or load `conversation.css` in that entry) so the shared frame remains valid wherever this component is rendered.</violation>
</file>

<file name="webviews/src/agent-session/acpmux/model.ts">

<violation number="1" location="webviews/src/agent-session/acpmux/model.ts:1541">
P2: The estimator always reserves the full 28px line frame, but the new step-row classes remove that frame's padding when a line is adjacent to another step. Pass the previous/next step adjacency into the estimator and subtract the corresponding top/bottom padding so initial layout matches the rendered row.</violation>
</file>

<file name="webviews/src/agent-session/acpmux/conversation/conversation.css">

<violation number="1" location="webviews/src/agent-session/acpmux/conversation/conversation.css:63">
P3: The new message-line alias follows the tight and roomy tool-spacing variants, but the row estimator still uses fixed 22px/4px constants. Keep the message line and frame fixed for gallery variants, or make the estimator consume the same configured spacing values.</violation>
</file>

<sub>Reply with feedback, questions, or to request a fix.

View guided diff | Turn on auto-fix | Re-trigger cubic</sub>

[cubic-dev-ai]

P2: This custom property is not defined in the acpmux production entry, so the declaration is dropped and message toggles lose their row height there. Add a local fallback (or load conversation.css in that entry) so the shared frame remains valid wherever this component is rendered.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. When an issue isn't valid or won't be fixed in this PR, reply in its thread with the reason and then resolve the thread. At webviews/src/agent-session/acpmux/conversation/AgentMessageRow.css, line 117:

<comment>This custom property is not defined in the acpmux production entry, so the declaration is dropped and message toggles lose their row height there. Add a local fallback (or load `conversation.css` in that entry) so the shared frame remains valid wherever this component is rendered.</comment>

<file context>
@@ -112,7 +112,9 @@ button.cv-agentmsg__name:focus-visible {
-  height: 26px;
+  /* The tool rows' line, so a message row is as tall as the rows around it (Leo, 2026-11-01:
+     "doesn't make sense for these to be spaced differently"). */
+  height: var(--cv-tool-row-height);
   cursor: default;
   border-radius: 4px;
</file context>

Suggested change

	height: var(--cv-tool-row-height);
	height: var(--cv-tool-row-height, 22px);

[teamleaderleo]

Review (codex gpt-6.1-sol xhigh, router-review): BLOCK at 3bd8fe3

BLOCK at 3bd8fe3

Visual verdict: no images; Leo tries the build

1. [P1] [blocking] model.ts:977 — Sent-message activity items still use the old estimator: generic SendMessage items return 26px, while cmux-subsessions.send_message returns 40px. Their rendered line is now 22px plus the 6px frame (28px). Unmounted rows therefore reserve too much space and collapse when virtualized into view, causing visible scroll/layout jumps and breaking the promised shared pitch.

[teamleaderleo]

Review (codex gpt-6.1-sol xhigh, router-review): BLOCK at f71b584

BLOCK at f71b584

Visual verdict: no images; Leo tries the build

1. [P1][blocking] Received and inbox labels retain a 26px child box inside the new 22px line. conversation.css:2874 constrains .cv-received__line to var(--cv-message-line), but DisclosureRow.css:19-29 leaves .cv-disclosure__open at min-height: var(--cv-disclosure-line-height) (26px). IncomingMessageLine and inbox threads both use this open button, so their previews are vertically offset and can be clipped/overlap adjacent 22px rows. The new rule at line 2892 only changes the chevron toggle’s height and does not reset the open button’s minimum height.

[github-actions]

cmux status _{(one comment, edited in place; each line is updated by the job that owns it)}

Review 501cbb2: HQ feed card · gallery before/after runs · checks

App of this head (app.zip, kept 1 day)

gh workflow run reload-build.yml -R manaflow-ai/cmux --ref feat-cmux-next -f tag=pr29965 -f ref=lane/transcript-row-pitch -f platform=macos -f backend_mode=local

Gallery before/after for 501cbb2: 16 states rendered, 18 images differ, 2797 more touched states not rendered. Images are in the run's artifact, not on this public PR; the independent review of this head reads them on its own, so the PR needs no hand-made screenshots of these states.

gh run download 41298184844 -R manaflow-ai/cmux -n gallery-advisory-29965-501cbb20cac945b019fb51316119e93d1d47e616 (then read gallery-review.json)

States

State	Theme	Status	Diff	Picked by
agent-pane.access-offer/turn-no-credits	Apple System Colors Light	unchanged	0%	own conversation.css
agent-pane.access-offer/turn-no-credits	Apple System Colors	unchanged	0%	own conversation.css
agent-pane.access-offer/turn-low-credits	Apple System Colors Light	unchanged	0%	own conversation.css
agent-pane.access-offer/turn-low-credits	Apple System Colors	unchanged	0%	own conversation.css
agent-pane.access-offer/turn-no-offer	Apple System Colors Light	unchanged	0%	own conversation.css
agent-pane.access-offer/turn-no-offer	Apple System Colors	unchanged	0%	own conversation.css
agent-pane.addressed-message/relayed	Apple System Colors Light	changed	2.47%	own LaneNoticeBatch.css
agent-pane.addressed-message/relayed	Apple System Colors	changed	2.46%	own LaneNoticeBatch.css
agent-pane.agent-message-row/unicode-boundary	Apple System Colors Light	changed	2.31%	own AgentMessageRow.css
agent-pane.agent-message-row/unicode-boundary	Apple System Colors	changed	2.3%	own AgentMessageRow.css
agent-pane.agent-message-row/sent	Apple System Colors Light	changed	7.13%	own AgentMessageRow.css
agent-pane.agent-message-row/sent	Apple System Colors	changed	7.09%	own AgentMessageRow.css
agent-pane.agent-message-row/lanes	Apple System Colors Light	changed	1.72%	own AgentMessageRow.css
agent-pane.agent-message-row/lanes	Apple System Colors	changed	1.7%	own AgentMessageRow.css
agent-pane.agent-message-row/sent-subagents	Apple System Colors Light	changed	3.23%	own AgentMessageRow.css
agent-pane.agent-message-row/sent-subagents	Apple System Colors	changed	3.19%	own AgentMessageRow.css
agent-pane.agent-message-row/sent-hover	Apple System Colors Light	changed	7.23%	own AgentMessageRow.css
agent-pane.agent-message-row/sent-hover	Apple System Colors	changed	7.19%	own AgentMessageRow.css
agent-pane.agent-message-row/sent-opened	Apple System Colors	changed	10.3%	own AgentMessageRow.css
agent-pane.agent-message-row/sent-opened	Apple System Colors Light	changed	10.2%	own AgentMessageRow.css
agent-pane.agent-message-row/sent-opened-long	Apple System Colors Light	changed	0.0149%	own AgentMessageRow.css
agent-pane.agent-message-row/sent-opened-long	Apple System Colors	changed	0.012%	own AgentMessageRow.css
agent-pane.agent-message-row/outcomes	Apple System Colors Light	changed	3.58%	own AgentMessageRow.css
agent-pane.agent-message-row/outcomes	Apple System Colors	changed	3.52%	own AgentMessageRow.css
agent-pane.approval-edits/single	Apple System Colors Light	unchanged	0%	own conversation.css
agent-pane.approval-edits/single	Apple System Colors	unchanged	0%	own conversation.css
agent-pane.approval-edits/grouped	Apple System Colors Light	unchanged	0%	own conversation.css
agent-pane.approval-edits/grouped	Apple System Colors	unchanged	0%	own conversation.css
agent-pane.approval-edits/single-multiedit	Apple System Colors Light	unchanged	0%	own conversation.css
agent-pane.approval-edits/single-multiedit	Apple System Colors	unchanged	0%	own conversation.css
agent-pane.approval-edits/grouped-multiedit	Apple System Colors Light	unchanged	0%	own conversation.css
agent-pane.approval-edits/grouped-multiedit	Apple System Colors	unchanged	0%	own conversation.css

_{Pick other states with a Gallery: entry.id, entry.id/variant line in the PR body.}

red: cmux-next checks (god files, concurrency, crash safety, l10n); base red: the same failure on the base c7c9a16; does not block

Shipped in:

• cmux NEXT nightly 1.0.0-nightly.4131171124701 (fe91ebac50)
• cmux NEXT nightly 1.0.0-nightly.4131261222601 (1c7090a384)
• cmux NEXT nightly 1.0.0-nightly.4131344025701 (c7caf1e32a)
• cmux NEXT nightly 1.0.0-nightly.4131523971401 (fa5830f6d5)
• cmux NEXT nightly 1.0.0-nightly.4131541733001 (49aa2917ea)

[blacksmith-sh]

Found 13 test failures on Blacksmith runners:

Failures

Test	View Logs
/tmp/tmp4uh5a7m9/summary-missing.json (live):/summary-missing.json (live):	View Logs
/tmp/tmpl_o2ko34/summary-fail.json (live):/summary-fail.json (live):	View Logs
[new_workspaces] debug.new_workspace timed 0 of 50 new workspace rows/ [new_workspaces] debug.new_workspace timed 0 of 50 new workspace rows	View Logs
[new_workspaces] the window draws no frames/[new_workspaces] the window draws no frames	View Logs
[tabs] debug.tab_switch timed 0 of 40 switches/ [tabs] debug.tab_switch timed 0 of 40 switches	View Logs
[tabs] the window draws no frames/[tabs] the window draws no frames	View Logs
main.DeveloperIdAppTests.test_download_prints_the_active_profile_only/ test_download_prints_the_active_profile_only	View Logs
nightly must build and hand off the macOS 26 helper and Xcode 26.5 app before publishin g/ nightly must build and hand off the macOS 26 helper and Xcode 26.5 app before publishin g	View Logs
stubs: /System/Library/Frameworks/Security.framework/Versions/A/Security has no stub/ Security has no stub	View Logs
stubs: CoreFoundation.tbd: install-name /System/Library/Frameworks/ CoreFoundation.framework/Versions/A/CoreFoundation, missing 1: ['_CFRetain']/ CoreFoundation, missing 1: ['_CFRetain']	View Logs

...and 3 more test failures. View all on Blacksmith

^{Need help on this PR? Tag @codesmith-bot with what you need.}

[cubic-dev-ai]

1 issue found across 1 file (changes from recent commits).

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. When an issue isn't valid or won't be fixed in this PR, reply in its thread with the reason and then resolve the thread. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="webviews/test/transcript-row-pitch-browser.test.ts">

<violation number="1" location="webviews/test/transcript-row-pitch-browser.test.ts:177">
P2: This assertion misses overflow from nested row parts: it measures the sentence/actions wrapper, not the controls inside it. Inspect all descendant elements so a 24px button or similar child cannot regress the one-line invariant without failing this test.</violation>
</file>

<sub>Reply with feedback, questions, or to request a fix.

View guided diff | Turn on auto-fix | Re-trigger cubic</sub>

[cubic-dev-ai]

P2: This assertion misses overflow from nested row parts: it measures the sentence/actions wrapper, not the controls inside it. Inspect all descendant elements so a 24px button or similar child cannot regress the one-line invariant without failing this test.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. When an issue isn't valid or won't be fixed in this PR, reply in its thread with the reason and then resolve the thread. At webviews/test/transcript-row-pitch-browser.test.ts, line 177:

<comment>This assertion misses overflow from nested row parts: it measures the sentence/actions wrapper, not the controls inside it. Inspect all descendant elements so a 24px button or similar child cannot regress the one-line invariant without failing this test.</comment>

<file context>
@@ -171,11 +171,20 @@ await requireBrowserLane("transcript-row-pitch-browser.test.ts", async () => {
+            // How far the line's own parts (its buttons, its sentence) stand out of its box.
+            const overhang = Math.max(
+              0,
+              ...[...el.children].map((child) => {
+                const part = child.getBoundingClientRect();
+                return part.height === 0 ? 0 : Math.max(box.top - part.top, part.bottom - box.bottom);
</file context>

Suggested change

	...[...el.children].map((child) => {
	...[...el.querySelectorAll<HTMLElement>("*")].map((child) => {

[teamleaderleo]

Review (codex, router-review): SHIP at 00c42fe

Reviewer: codex gpt-6-astra high, fast tier.

Follow-ups: 1. Each lands as an issue in this repo that links this receipt; the lane that opened the PR fixes it forward.

SHIP at 00c42fe

Visual verdict: no images; Leo tries the build

No correctness findings from static review. Tests could not run because Bun and webview dependencies are unavailable.

1. [P2] [follow-up] review/images/README.txt:2: No after screenshots were supplied; visual verification remains outstanding.

Follow-ups:

• Verify the transcript spacing and expanded disclosures in the build.

[cursor]

Bugbot needs on-demand usage enabled

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A team admin can enable on-demand usage in the Cursor dashboard.

[teamleaderleo]

Review (subagent opus-5.5 medium): SHIP at 9979dbb

router-review could not run at this head (the host's GraphQL quota was spent). The delta since the Codex SHIP at 0296ead is a base merge and one test assertion (a received line is 22px in agent-pane-suggested-tasks, which the webview base-check named). Independent read of the whole diff: cascade against styles.css user-row padding, last-turn, the status-edge rules and step joins; estimates against CSS for closed and opened received messages, notices, inbox notices (grouped, ungrouped, card), pending and lane-batch members, lastTurn and statusDelta. No blocking findings.

Follow-ups (filed as one issue):

1. A line row that is both the turn's last row and before another step row loses its turn gap (rule order); rare, and measurement corrects the estimate.
2. The waiting group as the chat's last row sits 4px over the composer's edge instead of 10px (matches a tool run there).
3. A sent message's 24px Copy overhangs its 22px line by 1px and can be clipped by the row's paint containment on hover when joined.
4. activityStepHeight checks agentMessage before dispatch / acpmux send calls, unlike toolGroups.ts (estimate only).
5. No rowEstimates case for a line row at a status edge.

CI at this head: transcript-row-pitch-browser, agent-pane-suggested-tasks, transcript-meta-columns-browser, transcript-row-alignment, incoming-message-disclosure-browser: 35 pass, 0 fail (https://github.com/manaflow-ai/cmux/actions/runs/41288684871).

[teamleaderleo]

Review (subagent opus-5.5 medium): SHIP at 501cbb2

This head only merges base (c7c9a16) into 9979dbb, which already had a SHIP.

• The merge resolution is right. git show --remerge-diff shows the only conflict was the App.tsx ./model import, and both sides were kept (isLineRow, then restRoom,). Nothing else in the PR's diff against the merge base changed.
• The change still works with the new base code:
  • restRoom (agent pane: rest the newest message 56px above the composer, with no shift on load #30297) assumes the last row ends with the turn gap. A last-turn line row still does: the CSS is article.acpmux-row--line.acpmux-row--last-turn with turn-gap padding, and the finish() estimate is TURN_GAP - TOOL_RUN_BOTTOM.
  • fix(agent-chat): folded runs with agent messages are estimated as the lines they draw (no scroll thumb jump) #30543 estimates folded runs with agent messages as one line each (foldedGroupHeight "send" is TOOL_ROW_HEIGHT). The PR's activityStepHeight gives agentMessage(tool) the same 22px.
  • On status edges, statusDelta treats line rows like a tool run (both end at TOOL_RUN_BOTTOM), which matches the article.acpmux-row--before-* padding rules.
• The design-tokens baseline merged cleanly. Running check-design-tokens locally flags session-info/sessionInfo.css, cloudStart.css and conversation.css (gap: 6px 14>13, padding: 3px 7px). All of these come from base: the files and their counts are the same at c7c9a16. None is the PR's own.
• bun test src/agent-session/acpmux/rowEstimates.test.ts: 23 pass, 0 fail. tsc ran out of memory on this host, so there is no local type result. The diff only adds a used import and a const of the existing type.
• The head still merges cleanly into the current feat-cmux-next tip.

Follow-ups:

• [follow-up] The estimator hardcodes 22px for line rows (LINE_ROW), but the density variants set --cv-tool-row-height to 20px or 26px (conversation.css about lines 1924 and 1928). Tool rows already do the same, and measured heights correct it after render, so all this costs is a small scroll-thumb jump on first paint in those densities.
• [follow-up] isLineRow includes inbox notices but isStatusRow does not. An inbox line between two replies gets the one-line frame but not the centred status gap that a message or notice line gets. This predates the PR and is only an inconsistency, not a regression.