[teamleaderleo]

Leo, 2026-10-30:

"subagents shouldn't be tab-named the exact same as the parent. and we dont want that subtitle text"

And, when asked which subtitle he meant (20:05Z):

"i mean the sidebar tab shouldn't just be named claude sr2 coord if you can just say it's SUbagent of sr2 coord / and yes ofc remove the second line a)"

This PR is the tab names: a subagent's pane is named after the subagent, else "Subagent of ", never the chat's bare name. The second line is #28510.

What was wrong

A subagent's pane is an agent tab on its chat's own acpmux session (AgentSubagentPanes). The tab strip and the sidebar's tab rows name an agent tab by its session (TabTitleResolver → AgentChatTabTitle), so the subagent's tab got exactly the chat's name, e.g. two "claude-sr2-coord" tabs.

What changes

• The page sends the subagent's name with chat.subagentPane (title): its own (Subagent.name: its task, which for the Agent tool is the call's description), else "Subagent of " from the page's already-translated subagents.of label (subagentTabTitle).
• The name follows what the pane shows. A pane opened on a subagent shows the chat's other subagents in place, and its "Subagent of" pill goes back to the chat. The page reports each change (chat.subagentShown, only once it has that subagent's rows), and the tab takes that subagent's name, or the chat's again.
• The app keeps it per tab (SubagentTabTitles, CmuxNextAgentPane). It's recorded by session and subagent id when the request arrives, then bound to the tab once that tab is created.
• TabTitleResolver.untitled reads it before the chat's title. A name the person gives the tab still wins, because displayTitle is read first. The strip and the sidebar's tab rows share that rule, so both change together.
• An older page that sends no name leaves the tab as before. The openSubagent hook keeps its signature.
• A subagent tab restored after a relaunch shows its whole chat, so it's named like the chat again.

Nothing else is removed or restyled. The "Subagent of …" pill and the sidebar subtitle are unchanged here.

Tests

• SubagentTabTitleTests:
  • the subagent's tab reads its own name while the chat keeps its own (before: identical);
  • the name follows what the pane shows, and clears back on the chat;
  • blank, unnamed, other-session, over-long and closed-tab cases;
  • both requests decode.
• webviews/test/subagent-pane-tab-title.test.ts: the request carries the name; a subagent with no name of its own gets "Subagent of ". 2 pass on cmux-ci, and lint passes.

Screenshots

Capture state scripts/cmux-next/media/states/subagents-four-panes.json (four fixture subagents opened beside a chat). Both sides carry #28213's debug open_subagent action and fixture agents count, which a showcase capture needs to open a subagent pane at all:

• before: 23db08cd511072ca368bbb397a2d302f4e67e671 = base df3ee368 + debug(next): the subagents fixture can start more than two subagents (agents), plus capture states #28213 6e063290.
• after: e2bd98ef1e9f624fa9a8d6f02e3cb52eb4e63629 = this PR 9d12f819 + debug(next): the subagents fixture can start more than two subagents (agents), plus capture states #28213, plus one stills-only line. debug(next): the subagents fixture can start more than two subagents (agents), plus capture states #28213's debug action calls the open hook directly and so skips chat.subagentPane; the line makes it record the fixture subagent's name ("Reviewer", "Auditor", "Helper N") the way a tray click's request does. That line goes into whichever of debug(next): the subagents fixture can start more than two subagents (agents), plus capture states #28213 and this PR lands second.

	Light	Dark
Before: every subagent's tab ("Right c…") and sidebar row ("Agent") reads like its chat
After: sidebar rows Reviewer, Auditor, Helper 1, Helper 2; tabs Review…, Audito…, Helper, Helper

Each subagent's sidebar row reads its own name (Reviewer, Auditor, Helper 1, Helper 2); the chat keeps its own row. The tab strip shows the same names, cut at this pane width. Nothing else in the window changes.

Viewed after image: yes
Visual verdict: SHIP: each subagent's row and tab carry its own name, as Leo would expect next to ChatGPT or Claude.

Not this PR: at this pane width the tab chips cut "Helper 1" and "Helper 2" to the same "Helper" (base cut "Right column" to "Right c" the same way). A tab-strip follow-up should keep a trailing number or truncate in the middle.

Agent session: agent session

🤖 Generated with Claude Code

[teamleaderleo]

Review (codex gpt-6-astra high, router-review): BLOCK at 995299f

BLOCK

Visual verdict: BLOCK — no after screenshots were supplied, so the required visual review cannot be completed.

1. [P2] Tab titles become incorrect after navigating within a subagent pane. TabTitleResolver.swift:77 always prefers the name cached when the tab opened. Existing navigation can show another subagent or return to the parent chat (App.tsx:6640, 6752) without updating or clearing that cache. Open “Reviewer,” then return through “Subagent of …”: both tab labels still say “Reviewer” while displaying the parent chat. Synchronize the override with the displayed subagent and clear it when returning to the chat.

2. Required visual evidence is missing. review/pr.body:32 says stills remain pending; review/images/ contains no screenshots. Supply the after images for comparison, and have the landing lane record in the PR body that it viewed them.

Tests could not run: this Linux box has neither Bun nor Swift installed.

[teamleaderleo]

Review (codex gpt-6-astra high, router-review): BLOCK at c4a360b

BLOCK

Visual verdict: BLOCK — no after screenshot is available (review/images/README.txt:1-2; PR body still says “Viewed after image: pending”).

1. Packages/macOS/CmuxNext/Sources/CmuxNextAgentPane/AgentPaneModel.swift:495 does not handle the new .subagentShown enum case. The exhaustive Swift switch therefore fails to compile.

2. Packages/macOS/CmuxNext/Sources/CmuxNextAgentPane/AgentPageProvider.swift:38 omits chat.subagentShown from AgentPageOps.methods. The page’s call at webviews/src/agent-session/acpmux/App.tsx:6673-6676 is rejected as an unknown native operation, so titles cannot follow pane navigation even after fixing the compile error.

[teamleaderleo]

Review (codex gpt-6-astra high, router-review): BLOCK at 9d12f81

BLOCK

Visual verdict: BLOCK — no after screenshot was provided (review/images/README.txt says none; PR body leaves the visual verdict pending), so the required UI review cannot be completed.

1. review/pr.body (Screenshots section): the landing lane has not viewed or supplied the after image for this UI change.

[teamleaderleo]

Visual verdict (Claude Opus 5.5, independent, opened the after stills): SHIP at 9d12f81 — the four subagent rows and tabs now carry their own names (Reviewer, Auditor, Helper 1, Helper 2) where before every one read the chat's ("Agent" rows, "Right c…" tabs), and nothing else in the window changes.

One follow-up, not this PR's: at this pane width the tab chips clip, so "Helper 1" and "Helper 2" both read "Helper" in the tab bar (the sidebar shows them in full). The same clipping cut "Right column" to "Right c" before. Worth a tab-bar follow-up (middle truncation, or keeping the trailing number), since two equal-looking tabs is what Leo complained about.

Fleet stills, state scripts/cmux-next/media/states/subagents-four-panes.json: before at 23db08c, after at e2bd98e (9d12f81 + #28213 + the stills-only naming line):

	light	dark
before (23db08c)
after (e2bd98e)

[github-actions]

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

Review dfa690a: 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=pr28497 -f ref=lane/ux-subagent-tab-name -f platform=macos -f backend_mode=local

Gallery before/after for dfa690a: 16 states rendered, 0 images differ, 1087 more touched states not rendered. Images are in the run's artifact, not on this public PR.

gh run download 41124020648 -R manaflow-ai/cmux -n gallery-advisory-28497-dfa690a5ce55ca9822b5495942be0d0bbb5a441d (then read gallery-review.json)

States

State	Theme	Status	Diff	Picked by
agent-pane.chat-width/standard	Apple System Colors Light	unchanged	0%	own App.tsx
agent-pane.chat-width/standard	Apple System Colors	unchanged	0%	own App.tsx
agent-pane.chat-width/wide	Apple System Colors Light	unchanged	0%	own App.tsx
agent-pane.chat-width/wide	Apple System Colors	unchanged	0%	own App.tsx
agent-pane.chat-width/wide-blocks	Apple System Colors Light	unchanged	0%	own App.tsx
agent-pane.chat-width/wide-blocks	Apple System Colors	unchanged	0%	own App.tsx
agent-pane.composer-edge/short-edge	Apple System Colors Light	unchanged	0%	own App.tsx
agent-pane.composer-edge/short-edge	Apple System Colors	unchanged	0%	own App.tsx
agent-pane.composer-edge/wide-edge	Apple System Colors Light	unchanged	0%	own App.tsx
agent-pane.composer-edge/wide-edge	Apple System Colors	unchanged	0%	own App.tsx
agent-pane.composer-edge/no-edge	Apple System Colors Light	unchanged	0%	own App.tsx
agent-pane.composer-edge/no-edge	Apple System Colors	unchanged	0%	own App.tsx
agent-pane.composer-floats/scrolled-to-end	Apple System Colors Light	unchanged	0%	own App.tsx
agent-pane.composer-floats/scrolled-to-end	Apple System Colors	unchanged	0%	own App.tsx
agent-pane.composer-floats/composer-grown	Apple System Colors Light	unchanged	0%	own App.tsx
agent-pane.composer-floats/composer-grown	Apple System Colors	unchanged	0%	own App.tsx
agent-pane.continuation-spacing/shipped	Apple System Colors Light	unchanged	0%	own App.tsx
agent-pane.continuation-spacing/shipped	Apple System Colors	unchanged	0%	own App.tsx
agent-pane.continuation-spacing/two-thirds	Apple System Colors Light	unchanged	0%	own App.tsx
agent-pane.continuation-spacing/two-thirds	Apple System Colors	unchanged	0%	own App.tsx
agent-pane.continuation-spacing/half-tucked	Apple System Colors Light	unchanged	0%	own App.tsx
agent-pane.continuation-spacing/half-tucked	Apple System Colors	unchanged	0%	own App.tsx
agent-pane.continuation-spacing/before	Apple System Colors Light	unchanged	0%	own App.tsx
agent-pane.continuation-spacing/before	Apple System Colors	unchanged	0%	own App.tsx
agent-pane.copy-controls/output	Apple System Colors Light	unchanged	0%	own App.tsx
agent-pane.copy-controls/output	Apple System Colors	unchanged	0%	own App.tsx
agent-pane.docked-chat/new-chat	Apple System Colors Light	unchanged	0%	own App.tsx
agent-pane.docked-chat/new-chat	Apple System Colors	unchanged	0%	own App.tsx
agent-pane.docked-chat/after-turn	Apple System Colors Light	unchanged	0%	own App.tsx
agent-pane.docked-chat/after-turn	Apple System Colors	unchanged	0%	own App.tsx
agent-pane.docked-chat/working	Apple System Colors Light	unchanged	0%	own App.tsx
agent-pane.docked-chat/working	Apple System Colors	unchanged	0%	own App.tsx

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

Passes: CI passes on dfa690a5ce.

CI passes on dfa690a5ce (run 41123928102 attempt 3).

Written by scripts/ci/classify_failures.py (ci-failure-attribution.yml); signatures are its SIGNATURES table. A machine verdict is the runner's fault, not this PR's; yours means the failing file is one this PR changes, also red on main that main's latest full suite fails the same way, seen on other PRs that it failed on another pull request's run lately.

web and size checks: green

Shipped in:

• cmux NEXT nightly 1.0.0-nightly.4115755828101 (7c0adaf184)
• cmux NEXT nightly 1.0.0-nightly.4115843934401 (8b3fa55ef5)
• cmux NEXT nightly 1.0.0-nightly.4115962701801 (631d310eb9)

[teamleaderleo]

Review (codex, router-review): SHIP at dfa690a

SHIP

Visual verdict: SHIP — viewed both after screenshots; no visual regressions.

1. No blocking findings. The targeted Bun test could not run because bun is unavailable in the review environment.