[teamleaderleo]

The picker keeps Add harness… in the existing harness strip. The compact and full pickers now end that strip with a clearly labelled + item; More models contains models only, and the model list no longer has a separate Add harness row.

Leo, word for word:

how the fuck was that your fucking first instinct? ... If you're thinking about adding a harness, where the fuck would you put it? If not already in the existing harnesses area, that section.

The + item is available in both the composer chat picker and New Tab picker, with the accessible name “Add harness…”. Existing model selection and harness rows remain unchanged. This is the d follow-up to #26071.

Keyboard behavior: the rail arrows reach the trailing Add action without changing the selected harness. Enter/Space keep native button activation. Returning to a harness restores focus even with a hidden search field. New Tab renders one Add action, and More models is absent when the harness has no extra models.

Validation:

• Branch base: dfdfc55265f4d5caefa8b8148618ee368382fc98 (fix(composer): align search fields with menu rows #26589).
• Head: add512615797846ae25d1f380f8fc5bbe260a1dc.
• Focused verification: run 40657628190. Both return-from-Add regressions fail against a033e89; all three focused files pass at add512615797 without retries (model-picker-picks, QuickModelMenu, new-tab-add-harness-chip). The full webviews check passes: formatting, lint, typecheck, guards, and generated protocol.
• The empty-search keyboard repair lets ArrowDown reach Add harness and Enter activate it; returning through the current harness or directly to search clears Add so Enter selects the model; the New Tab gallery play now checks the rail action and models-only More models.
• Gallery comparison: run 40648057223 rendered the More models play in both themes. The base and head share the existing disclosure-step base red: base layout shift 0.068107, head 0.069632 in both themes (the 0.001525 increase is ~2.2%); this is recorded as a base red and the disclosure source is unchanged.

Gallery: new-tab.quick-model-menu/combined, new-tab.quick-model-menu/claude, new-tab.quick-model-menu/claude-more-models, agent-pane.model-picker/quick-menu

Before / after

Synthetic gallery captures from advisory run 40644096979, rendered at base dfdfc552 and the pre-repair visual head c588a33. The follow-up commits only repair keyboard activation and gallery assertions, so these visual states are unchanged at final head add512615797; the captures contain no private data.

State	Base light	Head light	Base dark	Head dark
Combined menu
Claude menu
Claude More models

The rail action is a + Add harness item in the head; More models contains models only. The full picker and compact picker preserve the existing menu model list.

---

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

---

Summary by cubic

Keeps "Add harness…" in the harness rail so both the compact and full pickers end the strip with a clearly labelled + item instead of a row in the model list.

• "More models" now contains models only; the separate Add row is gone from the model list and submenu.
• The Add rail item is reachable via click and rail arrows; focus moves between it and neighboring harness tabs without changing the selection.
• Rail arrows reach Add even when search is hidden, empty, or the picker has no matches, with focus wrapping between Add and the Starred tab.
• Cmd-Ctrl-M over the compact menu now replaces it with the full picker instead of keeping the compact menu open.

^{Written for commit 655b347. Summary will update on new commits.}

Agent session: agent session

[github-actions]

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

Review 655b347: 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=pr26503 -f ref=lane/picker-add-harness -f platform=macos -f backend_mode=local

Gallery before/after for 655b347: 4 states rendered, 6 images differ (picked by the Gallery: line in the PR body). Images are in the run's artifact, not on this public PR.

gh run download 40869397792 -R manaflow-ai/cmux -n gallery-advisory-26503-655b347ebc990be6e2586e4b71c694bb05a5b958 (then read gallery-review.json)

States

State	Theme	Status	Diff	Picked by
new-tab.quick-model-menu/combined	Apple System Colors Light	changed	0.179%	pr-body
new-tab.quick-model-menu/combined	Apple System Colors	changed	0.178%	pr-body
new-tab.quick-model-menu/claude	Apple System Colors Light	changed	0.179%	pr-body
new-tab.quick-model-menu/claude	Apple System Colors	changed	0.178%	pr-body
new-tab.quick-model-menu/claude-more-models	Apple System Colors Light	changed	2.77%	pr-body
new-tab.quick-model-menu/claude-more-models	Apple System Colors	changed	2.58%	pr-body
agent-pane.model-picker/quick-menu	Apple System Colors Light	unchanged	0%	pr-body
agent-pane.model-picker/quick-menu	Apple System Colors	unchanged	0%	pr-body

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

Unclear: web / react-apps-check failed: no known signature; failed step: Check webview test shards.

CI failed on 655b347ebc (run 40869398275 attempt 1): 2 code, 1 unknown.

Job	Verdict	Why
web / react-apps-base-check (1)	code	a web test failed
web / react-apps-base-check (4)	code	a web test failed
web / react-apps-check	unknown	no known signature; failed step: Check webview test shards

Failures:

• seen on other PRs MarkdownMath.test.tsx keeps shell command dollar signs as plain text without dropping content: failed (job)
• seen on other PRs chiefLook.test.tsx search renders Bubble Style in the Look card: failed (job)
• seen on other PRs rowSummary.test.tsx no description line on any Settings page is over 60 characters, in any language: failed (job)
• seen on other PRs rowSummary.test.tsx every schema summary fits 60 characters in every language: failed (job)
• seen on other PRs themePane.test.tsx the Theme page draws each theme key once, in one card, with no second App Theme group: failed (job)
• seen on other PRs agent-pane-pending-steer.test.tsx Send now on a waiting steer asks queue_edit send_now for its promptId, and goes once it is read: failed (job)
• seen on other PRs clickable-cursor.test.ts no stylesheet sets the arrow or auto on a clickable element: failed (job)
• seen on other PRs motion-scale.test.ts motion scale > no webview CSS, TS or TSX animates off the scale: failed (job)
• seen on other PRs inspector-section-order-browser.test.tsx Session Info's six-dot handles > every section has one: failed (job)

Matched log lines

web / react-apps-base-check (1): (fail) keeps shell command dollar signs as plain text without dropping content [5.10ms]
web / react-apps-base-check (4): (fail) Session Info's six-dot handles > every section has one [0.41ms]

Not re-run automatically: web / react-apps-base-check (1), web / react-apps-base-check (4), web / react-apps-check are not machine failures.

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.

red: cmux-next checks (god files, concurrency, crash safety, l10n); base red: the same failure on the base 3f83053; does not block
red: web / Web status; base red: the same failure on the base 3f83053; does not block
red: web / react-apps-base-check (1); no finished base run on 3f83053 to compare; do not merge until green; see lane-rules
red: web / react-apps-base-check (4); no finished base run on 3f83053 to compare; do not merge until green; see lane-rules
red: web / react-apps-check; base red: the same failure on the base 3f83053; does not block

[blacksmith-sh]

Found 28 test failures on Blacksmith runners:

Failures

Test	View Logs
/tmp/tmp1ykyvi76/summary-fail.json (live):/summary-fail.json (live):	View Logs
/tmp/tmp_qdyagy1/summary-missing.json (live):/summary-missing.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
src/agent-session/acpmux/conversation/MarkdownMath.test.tsx/MarkdownMath.test.tsx	View Logs
src/agent-session/acpmux/conversation/MarkdownMath.test.tsx/MarkdownMath.test.tsx	View Logs
src/pages/settings/chiefLook.test.tsx/chiefLook.test.tsx	View Logs
src/pages/settings/chiefLook.test.tsx/chiefLook.test.tsx	View Logs

...and 18 more test failures. View all on Blacksmith

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

[teamleaderleo]

Bead cx-0ol685 created for this PR by the cmux coordinator.

[teamleaderleo]

Review (codex gpt-6-astra high, next-review): BLOCK at 1db2878

• ModelPicker.tsx:1279-1285 — The new + option is always active={false} and has no keyboard handler. PickerOption therefore gives it tabIndex=-1; rail arrow navigation only traverses harness tabs, so keyboard users cannot reach or activate “Add harness…”.
• QuickModelMenu.tsx:575-578 — New Tab’s inline “More models” path still renders a textual Add harness item. The new rail button is also rendered at :779, leaving duplicate Add harness controls and violating the strip-only behavior.
• QuickModelMenu.tsx:635-664 — The chat compact menu still creates a More models submenu when onAddHarness is present even if there are no older models. After removing the Add harness child, that submenu can be empty.

[teamleaderleo]

Orphaned: no activity for 12 h, and no lane holds a lease on it. The orphan sweep could not merge feat-cmux-next in: conflicts in webviews/test/model-menu-compact.test.tsx. Listed for a lane to resolve.

[teamleaderleo]

Owned by an agent session · took over from an earlier session · session

[teamleaderleo]

Review (codex gpt-6-astra high, review-router): SHIP at 655b347

No blocking findings at this head (base merge plus conflict resolution reviewed with the full diff).

Agent session: agent session

[github-actions]

Shipped in:

• cmux NEXT nightly 1.0.0-nightly.4090194435201 (7d713b7de1)
• cmux NEXT nightly 1.0.0-nightly.4090568854201 (8232b611fe)