[teamleaderleo]

Answering an agent's question in the Mac app's chat pane failed for a chat on an ssh peer (Leo hit it live on huge-blue): the peer's acpmux refused it with "approve this on the Mac app: allowing a permission is accepted only from the cmux app".

Cause

A chat on another machine gets its answers through a connection that is never the person, so the peer counts an allow only with the person's decision proof (cx-0q7o). That proof never covered question answers: person_decided and respond_permission refused any proof when answers was present. Every AskUserQuestion answered in the pane for a peer chat was refused. The rule dates from the design (9c4543d), not a recent change.

Fix

• acpmux: a new proof acpmux-person-decision-answers-v1 covers the answers too: the allow's five parts plus the sha256 of the canonical answers JSON, the same digest a phone's signed answer uses (approvers::answers_digest). An answer counts only under that proof, so a relay still cannot swap the answers; a plain allow keeps the v1 proof. Nonces are still spent once, under the prompt's lock.
• Mac pane: signRelayedAllow signs a frame's answers with the bound key (AcpmuxSecretKey.decisionProof(..., answers:), canonical JSON byte-for-byte as acpmux's).
• A shared vector (the same key, inputs and expected proof in a Rust and a Swift test) keeps the two sides' bytes equal.
• Pane page: an answer now takes the person's gesture ticket for its session, prompt and option, as an option pick does (direct.ts), and the Swift pick no longer skips frames with answers (AgentPaneGestureIntent.swift). Without the ticket the host never signed the answer, so the first fix alone did not reach the peer (the review caught this).

The ticket covers the click on the option, not the answers themselves: the page fills the answers in after the person's click, which is the same trust the local daemon already gives the page. The proof then binds those exact answers, so nothing past the host can change them. answeredBy is not covered by the proof, as with plain allows.

The peer must run an acpmux with this change; an older peer keeps refusing the same way.

Tests

• cargo test -p acpmux --test person_allow a_relayed_answer_counts_with_the_persons_proof_over_exactly_its_answers and the_answers_decision_proof_matches_the_apps_vector: red on f078763 (the test commit; the answer is refused, the vector does not compile), green on the head.
• Web: cd webviews && bun test src/agent-session/acpmux/questionAnswerTicket.test.ts: red at bf80b32 (fleet step ff550a72710e1b8e2ae50508: "a question's answer carries the person's ticket for its session, prompt and option" fails), green at 8028cf3 (0 failed).
• Swift: AgentPaneRelayedAllowTests anAnswerToAnotherMachinesQuestionCarriesTheProofOverItsAnswers and theAnswersProofMatchesAcpmuxsVector.

Observed / Not run

• Observed: fleet cmux-ci compile-check --app passed at 8028cf3 (job b352dc53c1eaf8fe20455a0d). Independent review: SHIP at 8028cf3. scripts/cmux-next/prepush-gate.py passes; rustfmt --check is clean. The Rust vector was computed independently with Python (HMAC-SHA256 over the canonical JSON).
• Not run on this Mac: the cargo and Swift tests above (no local builds here); they run on CI for this head. Not dogfooded against huge-blue.
• Reds at this head that are not this PR's: cmux-next crash-class rules (CEFFileDragRelay.swift:162 needs a selector probe), cmux-next web bundles and react-apps-check (inspector/ContextSection.css is missing from build-agent-pane-web.sh), and cmux-next CI guard group (workflow-guard-tests on workflow files). None of those files are in this diff.

No capture: the change is in the proof and the gesture plumbing, and the question card looks the same.

Changelog

Fixed: Answering an agent's question in a chat on another machine no longer fails with "accepted only from the cmux app".

risk:high: this changes what the person's decision proof covers (auth).

Agent session: cosmic-gray

🤖 Generated with Claude Code

---

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

---

Summary by cubic

Fixes answering an agent's question in the Mac app's chat pane for a chat on another machine, which the peer's acpmux always refused with "accepted only from the cmux app".

A relayed allow's decision proof never covered question answers. The pane now signs an answer with acpmux-person-decision-answers-v1 — the allow's five parts plus the sha256 of the canonical answers JSON — and acpmux counts an answer only under that proof, so a relay cannot swap the answers. An answer also takes the person's gesture ticket for its session, prompt and option, as an option pick does.

The answer's answers now reach that machine's acpmux: RemoteAcpmuxWire and agent-session-permission previously dropped or refused them, so the peer checked the answers proof against a plain allow and refused the answer. The daemon passes a JSON object of at most 64 KiB to acpmux unchanged.

The peer must run an acpmux with this change; an older peer still refuses the answer.

^{Written for commit 5afde6f. 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 5afde6f: 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=pr23869 -f ref=cmux/pane-person-proof -f platform=macos -f backend_mode=local

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

CI failed on 5afde6fc34 (run 39841951809 attempt 1): 1 code, 1 unknown.

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

Failures:

• seen on other PRs agent-pane-jump-latest-motion.test.ts chromium: a reply streaming in during Jump to latest's glide is followed to its latest row: failed (job)
• seen on other PRs agent-pane-jump-latest-motion.test.ts webkit: a reply streaming in during Jump to latest's glide is followed to its latest row: failed (job)
• seen on other PRs agent-pane-no-capsules.test.ts agent pane page > rounds its controls as small-radius rects, not capsules: failed (job)
• seen on other PRs agent-pane-peer-chat.test.ts a chat on an SSH machine > counts its running turn from the prompt and offers no machine switch mid-...: failed (job)
• seen on other PRs composer-edges.test.ts composer card: appearance.borders = none draws no edge: failed (job)
• seen on other PRs composer-edges.test.ts composer card: one hairline edge by default: failed (job)
• seen on other PRs composer-foot-pill-inset.test.ts the row's padding is counted from the inset, so only the pill grows, not the text's place: failed (job)
• seen on other PRs composer-location-strip.test.ts the chat composer: no hairline across the seam under the strip: failed (job)

Matched log lines

web / react-apps-check (1): (fail) chromium: a reply streaming in during Jump to latest's glide is followed to its latest row [5154.14ms]

Not re-run automatically: web / react-apps-check (1), 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); no finished base run on 44fc3d3 to compare; do not merge until green; see lane-rules
red: web / Web status; NEW: green on the base 44fc3d3; do not merge until green; see lane-rules
red: web / react-apps-check; no finished base run on 44fc3d3 to compare; do not merge until green; see lane-rules
red: web / react-apps-check (1); no finished base run on 44fc3d3 to compare; do not merge until green; see lane-rules

Gallery before/after for 5afde6f: 16 states rendered, 3 images differ, 1587 more touched states not rendered. Images are in the run's artifact, not on this public PR.

gh run download 39841951518 -R manaflow-ai/cmux -n gallery-advisory-23869-5afde6fc3410a25165e28debb126b1abe800af29 (then read gallery-review.json)

States

State	Theme	Status	Diff	Picked by
agent-pane.chat-width/standard	Apple System Colors Light	unchanged	0%	imports direct.ts (1 hops)
agent-pane.chat-width/standard	Apple System Colors	unchanged	0%	imports direct.ts (1 hops)
agent-pane.chat-width/wide	Apple System Colors Light	unchanged	0%	imports direct.ts (1 hops)
agent-pane.chat-width/wide	Apple System Colors	unchanged	0%	imports direct.ts (1 hops)
agent-pane.chat-width/wide-blocks	Apple System Colors Light	unchanged	0%	imports direct.ts (1 hops)
agent-pane.chat-width/wide-blocks	Apple System Colors	unchanged	0%	imports direct.ts (1 hops)
agent-pane.composer-floats/scrolled-to-end	Apple System Colors Light	unchanged	0%	imports direct.ts (1 hops)
agent-pane.composer-floats/scrolled-to-end	Apple System Colors	unchanged	0%	imports direct.ts (1 hops)
agent-pane.composer-floats/composer-grown	Apple System Colors Light	unchanged	0%	imports direct.ts (1 hops)
agent-pane.composer-floats/composer-grown	Apple System Colors	unchanged	0%	imports direct.ts (1 hops)
agent-pane.docked-chat/new-chat	Apple System Colors Light	unchanged	0%	imports direct.ts (1 hops)
agent-pane.docked-chat/new-chat	Apple System Colors	unchanged	0%	imports direct.ts (1 hops)
agent-pane.docked-chat/after-turn	Apple System Colors Light	unchanged	0%	imports direct.ts (1 hops)
agent-pane.docked-chat/after-turn	Apple System Colors	unchanged	0%	imports direct.ts (1 hops)
agent-pane.docked-chat/working	Apple System Colors Light	unchanged	0%	imports direct.ts (1 hops)
agent-pane.docked-chat/working	Apple System Colors	unchanged	0%	imports direct.ts (1 hops)
agent-pane.docked-chat/typing-in-dock	Apple System Colors Light	unchanged	0%	imports direct.ts (1 hops)
agent-pane.docked-chat/typing-in-dock	Apple System Colors	unchanged	0%	imports direct.ts (1 hops)
agent-pane.docked-chat/long-title	Apple System Colors Light	unchanged	0%	imports direct.ts (1 hops)
agent-pane.docked-chat/long-title	Apple System Colors	unchanged	0%	imports direct.ts (1 hops)
agent-pane.inspector/chat-menu	Apple System Colors	changed	0%	imports direct.ts (1 hops)
agent-pane.inspector/chat-menu	Apple System Colors Light	unchanged	0%	imports direct.ts (1 hops)
agent-pane.inspector/wire-log	Apple System Colors	changed	0.0342%	imports direct.ts (1 hops)
agent-pane.inspector/wire-log	Apple System Colors Light	changed	0.017%	imports direct.ts (1 hops)
agent-pane.orchestration-lab/local-queue	Apple System Colors Light	unchanged	0%	imports direct.ts (1 hops)
agent-pane.orchestration-lab/local-queue	Apple System Colors	unchanged	0%	imports direct.ts (1 hops)
agent-pane.orchestration-lab/build-box	Apple System Colors Light	unchanged	0%	imports direct.ts (1 hops)
agent-pane.orchestration-lab/build-box	Apple System Colors	unchanged	0%	imports direct.ts (1 hops)
agent-pane.orchestration-lab/cloud-fair-share	Apple System Colors Light	unchanged	0%	imports direct.ts (1 hops)
agent-pane.orchestration-lab/cloud-fair-share	Apple System Colors	unchanged	0%	imports direct.ts (1 hops)
agent-pane.permission-panel/buttons-current	Apple System Colors Light	unchanged	0%	imports direct.ts (1 hops)
agent-pane.permission-panel/buttons-current	Apple System Colors	unchanged	0%	imports direct.ts (1 hops)

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

[blacksmith-sh]

Found 47 test failures on Blacksmith runners:

Failures

Test	View Logs
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/tmp/tmp_6wzvvy2/summary-missing.json (live):/summary-missing.json (live):	View Logs

...and 37 more test failures. View all on Blacksmith: run 39841951723, run 39841951809, run 39841951667

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

[teamleaderleo]

cmux-next crash-class rules / cmux-next crash-class rules is red on 8 of 8 fresh feat-cmux-next PR heads in the last 2:00:00, so it is most likely a base red, not this PR's. The base-reds lane has it; a base merge picks up the fix once it lands.

[teamleaderleo]

cmux-next guards / cmux-next localization debt ratchet is red on 14 of 15 fresh feat-cmux-next PR heads in the last 2:00:00, so it is most likely a base red, not this PR's. The base-reds lane has it; a base merge picks up the fix once it lands.

[teamleaderleo]

Owned by hb-acpmux on big-red · session

[teamleaderleo]

Review (independent subagent): SHIP at 8028cf3. Fleet compile-check --app passed at that head (job b352dc53c1eaf8fe20455a0d). Reds at this head are base: crash-class rules (CEFFileDragRelay.swift:162 selector probe), web bundles/react-apps-check (inspector/ContextSection.css missing from build-agent-pane-web.sh), CI guard group (workflow-guard-tests); none of those files are in this diff.

[cursor]

Bugbot needs on-demand usage enabled

Bugbot uses usage-based billing for this team and requires on-demand usage to be enabled.

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

[teamleaderleo]

Orphaned: no activity for 15 h, and no lane holds a lease on it. Adopted by the orphan sweep: merged feat-cmux-next in at 5afde6f. A later pass queues it for the merge hub if it is reviewed, small and red only on base reds.

[teamleaderleo]

cmux-next guards / nightly-guards / workflow-guard-tests / release-notary is red on 21 of 22 fresh feat-cmux-next PR heads in the last 2:00:00, so it is most likely a base red, not this PR's. The base-reds lane has it; a base merge picks up the fix once it lands.

[teamleaderleo]

cmux-next / cmux-next checks (god files, concurrency, crash safety, l10n) › Checks job structure is red on 19 of 19 fresh feat-cmux-next PR heads in the last 2:00:00, so it is most likely a base red, not this PR's. The base-reds lane has it; a base merge picks up the fix once it lands.

[teamleaderleo]

cmux-next / cmux-next checks (god files, concurrency, crash safety, l10n) › No fleet host names in gallery fixtures is red on 17 of 17 fresh feat-cmux-next PR heads in the last 2:00:00, so it is most likely a base red, not this PR's. The base-reds lane has it; a base merge picks up the fix once it lands.

[teamleaderleo]

cmux-next / cmux-next checks (god files, concurrency, crash safety, l10n) › No new SwiftUI (macOS UI is AppKit) is red on 17 of 17 fresh feat-cmux-next PR heads in the last 2:00:00, so it is most likely a base red, not this PR's. The base-reds lane has it; a base merge picks up the fix once it lands.

[teamleaderleo]

cmux-next / cmux-next swift test is red on 12 of 17 fresh feat-cmux-next PR heads in the last 2:00:00, so it is most likely a base red, not this PR's. The base-reds lane has it; a base merge picks up the fix once it lands.

[teamleaderleo]

Re-cut as #25424, rebased onto feat-cmux-next. This branch isn't under the adopting lane's push prefix, so the work moves there. Credit for the work stays with this PR. Adopted by hb-acpmux after the stale-pr-reconciler flagged this PR as orphaned.