[teamleaderleo]

Fixes #30894.

Leo, 2026-11-01, on the Cloud sign-in card: "yes those are important".

A new Cloud chat had no sign-in offer on its first failed turn. Its wire (RemoteAcpmuxWire(start:)) has no session client during initialize, so it never named agent_login. The page reads features only at initialize, so the offer stayed hidden until the chat reconnected.

The fix:

• AgentTabs+Wiring: sets the host's servesLogin from the machine daemon's agent-session-login-v1, the same read that servesTrust and servesKeyedReason already use.
• AgentTabRemoteHost: passes it to the start wire.
• RemoteAcpmuxWire: names agent_login from it until a session client exists, then asks the client as before.

Test: RemoteAcpmuxLoginTests.aNewChatNamesTheFeatureBeforeItsFirstSend covers a new chat whose daemon serves the relay and one whose daemon doesn't, each with and without a Cloud owner answer.

Risk: low. An observer never takes the start route, and a wire that already has a session is unchanged.

Agent session: agent session

🤖 Generated with Claude Code

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Summary by cubic

Fixes #30894. A new Cloud chat now offers Sign in from its first failed turn; previously the offer appeared only after the chat reconnected, because the start wire has no session client during initialize and so never named agent_login.

• AgentTabs+Wiring sets the host's servesLogin from the daemon's agent-session-login-v1, the same read that servesTrust and servesKeyedReason use.
• AgentTabRemoteHost passes that flag to the start wire, and RemoteAcpmuxWire names agent_login from it until a session client exists.
• A wire that already has a session keeps asking its client, so existing behavior is unchanged.
• Adds a test covering new chats with and without a serving daemon, each with and without a Cloud owner answer.

^{Written for commit f1020e8. Summary will update on new commits.}

[github-actions]

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

Review f1020e8: 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=pr31147 -f ref=cloud-login-new-chat -f platform=macos -f backend_mode=local

red: cmux-next checks (god files, concurrency, crash safety, l10n); no finished base run on 377187a to compare; do not merge until green; see lane-rules

Shipped in:

• cmux NEXT nightly 1.0.0-nightly.4133598742701 (1e1948befb)
• cmux NEXT nightly 1.0.0-nightly.4133716725501 (d30463325c)
• cmux NEXT nightly 1.0.0-nightly.4133769596201 (0272db645e)
• cmux NEXT nightly 1.0.0-nightly.4133822529301 (68e3df851b)
• cmux NEXT nightly 1.0.0-nightly.4133907849701 (c2ef233b76)
• cmux NEXT nightly 1.0.0-nightly.4133963836301 (48e4448d11)
• cmux NEXT nightly 1.0.0-nightly.4134024448601 (94322a6ccf)

[teamleaderleo]

Owned by an agent session · session

[blacksmith-sh]

Found 7 test failures on Blacksmith runners:

Failures

Test	View Logs
/tmp/tmpsod72vc6/summary-fail.json (live):/summary-fail.json (live):	View Logs
/tmp/tmpuut9m969/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
test_runtime_added_app_capabilities_are_runtime_only (main.StaticCapabilityRuntimeO nlyTests.test_runtime_added_app_capabilities_are_runtime_only)/ test_runtime_added_app_capabilities_are_runtime_only (main.StaticCapabilityRuntimeO nlyTests.test_runtime_added_app_capabilities_are_runtime_only)	View Logs

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[teamleaderleo]

Review (independent Codex gpt-6.1-sol, high, via the review router; full diff from merge base 377187a to this head): SHIP at f1020e8.

No P1/P2 findings.

[teamleaderleo]

Review (subagent opus 5.5 medium): SHIP at f1020e8

No blocking findings. It checked the Swift 6 captures, both initialize branches, that no observer or read-only path can advertise the feature, and the new test.

Follow-ups:

• [follow-up] A new chat reads the machine's daemon through daemon.supports, while an attached chat reads its own connection through identity.supports. If the two ever answered agent-session-login-v1 differently, Sign in could show on the first turn and then disappear after a reconnect.

Checks at this head: the fleet app compile passed; the webview verdict is green; RemoteAcpmuxLoginTests passed on a fleet Mac, including aNewChatNamesTheFeatureBeforeItsFirstSend.