feat(LAC-1432): parallel background agent sessions — registry wiring, input arbiter, per-session cursors, roster UI, notifications - #474
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Salvaged uncommitted work from the stale LAC-1400 worktree during LAC-2841 workspace repair. Not yet compiled or reviewed — resume on this branch when LAC-1432 work restarts. Co-Authored-By: Paperclip <noreply@paperclip.ing>
Wire the salvaged session registry + input arbiter scaffolding (commit 4d12e53) into a real Tauri command surface so the frontend session-switcher and status bar can render, focus, and cancel parallel agent sessions without polling. - `commands/agent_sessions.rs`: list_agent_sessions, get_focused_agent_session, focus_agent_session, cancel_focused_agent_session, cancel_agent_session - New event constants `agent-sessions-updated` (full snapshot on every mutation) and `agent-session-focused` (focus change payload so cursor overlays can react without diffing the list) - Register commands module + wire the five commands into `generate_handler!` - Scaffolding + commands compile clean under `cargo check`; 5/5 session-registry tests and 2/2 command tests pass Follow-up on this branch will: - Wire session lifecycle into `submit_query` / orchestrator so sessions are created and removed as agents start and finish - Ship the frontend switcher + per-session cursor overlay windows Co-Authored-By: Paperclip <noreply@paperclip.ing>
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Code Review
This pull request introduces parallel agent sessions (LAC-1432) by adding an InputArbiter to serialize physical input, an AgentSessionRegistry to manage parallel session lifecycles, and Tauri commands to expose these sessions to the frontend. The review feedback suggests several improvements: replacing TokioMutex with a synchronous mutex for synchronous state to avoid async overhead, simplifying the focus check in session creation, optimizing the remove method to avoid dropping and re-locking the sessions map, and centralizing the default cooldown duration as a public constant.
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| pub struct AgentSession { | ||
| id: AgentSessionId, | ||
| agent_name: String, | ||
| display_color: String, | ||
| cancel_tx: watch::Sender<bool>, | ||
| cancel_rx: watch::Receiver<bool>, | ||
| started_at_ms: u64, | ||
| inner: TokioMutex<AgentSessionInner>, | ||
| } |
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Performance & Complexity: Unnecessary use of TokioMutex
Using tokio::sync::Mutex (TokioMutex) for guarding synchronous state that is never held across .await points is a known anti-pattern in asynchronous Rust. It introduces significant overhead (future allocation, async scheduling) and forces purely synchronous operations (like updating status, setting current action, or taking a snapshot) to be async fns.
Since AgentSessionInner is only updated and read synchronously, you should use std::sync::Mutex (or parking_lot::Mutex) instead. This allows you to simplify all of these methods into standard synchronous fns, improving both performance and code readability.
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Keeping TokioMutex here deliberately. Since this comment was written, the truly-sync registry state (focused, colors) was migrated to std::sync::Mutex (commit 89de83b). AgentSessionInner stays behind an async mutex per this repo's convention (src-tauri/CLAUDE.md: Arc<TokioMutex<T>> for state touched from the async execution loop): snapshot() is awaited from list()/mark_terminal() on the agent hot path, and the upcoming needs-input wiring (LAC-3072) will add awaits inside status transitions — a std mutex there would then have to be reverted. Perf impact is negligible at the ≤12-session cap with human-scale update cadence. Won't fix in this PR.
| // Auto-focus the first session so escape has an obvious target. | ||
| let mut focused = self.focused.lock().await; | ||
| if focused.is_none() { | ||
| *focused = Some(id.clone()); | ||
| } | ||
| info!( | ||
| "Registered agent session {} (focused={})", | ||
| id, | ||
| focused.as_ref().map(|f| f == &id).unwrap_or(false) | ||
| ); | ||
| Ok(session) |
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Readability: Simplify focus check
We can simplify the check focused.as_ref().map(|f| f == &id).unwrap_or(false) to focused.as_ref() == Some(&id). This is much more idiomatic and easier to read.
| // Auto-focus the first session so escape has an obvious target. | |
| let mut focused = self.focused.lock().await; | |
| if focused.is_none() { | |
| *focused = Some(id.clone()); | |
| } | |
| info!( | |
| "Registered agent session {} (focused={})", | |
| id, | |
| focused.as_ref().map(|f| f == &id).unwrap_or(false) | |
| ); | |
| Ok(session) | |
| // Auto-focus the first session so escape has an obvious target. | |
| let mut focused = self.focused.lock().await; | |
| if focused.is_none() { | |
| *focused = Some(id.clone()); | |
| } | |
| info!( | |
| "Registered agent session {} (focused={})", | |
| id, | |
| focused.as_ref() == Some(&id) | |
| ); | |
| Ok(session) |
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Addressed — create() was rewritten during review round 1 and no longer compares at all: it computes let is_focused = focused.is_none(); before the assignment and logs that. The remaining focused.as_ref() == Some(id) comparisons elsewhere in the file already use the idiomatic form you suggested.
| pub async fn remove(&self, id: &AgentSessionId) { | ||
| let mut sessions = self.sessions.lock().await; | ||
| if sessions.remove(id).is_some() { | ||
| debug!("Removed agent session {} from registry", id); | ||
| } | ||
| drop(sessions); | ||
|
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||
| let mut focused = self.focused.lock().await; | ||
| if focused.as_ref() == Some(id) { | ||
| *focused = None; | ||
| let sessions = self.sessions.lock().await; | ||
| if let Some(next) = sessions.keys().next().cloned() { | ||
| *focused = Some(next); | ||
| } | ||
| } | ||
| } |
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Efficiency & Correctness: Simplify remove and avoid dropping/re-locking
In the current implementation of remove, the sessions lock is dropped and then re-acquired inside the focused lock block to find the next session. This is inefficient and introduces a potential race condition where the sessions map could be modified in between.
By keeping the sessions lock active and locking focused afterwards, you can safely and atomically reassign the focus using sessions.keys().next().cloned() directly without dropping and re-locking.
pub async fn remove(&self, id: &AgentSessionId) {
let mut sessions = self.sessions.lock().await;
if sessions.remove(id).is_some() {
debug!("Removed agent session {} from registry", id);
}
let mut focused = self.focused.lock().await;
if focused.as_ref() == Some(id) {
*focused = sessions.keys().next().cloned();
}
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Fixed in c52a00b, with a variant of your suggestion: focus is now reassigned via sessions.keys().next().cloned() while the sessions lock is still held, closing the window where a concurrent remove() could delete the captured candidate. One deviation from the suggested diff: focused is a std::sync::Mutex (not a second async mutex) held only for a brief no-await block — this repo bans holding two async mutexes simultaneously (deadlock-prevention rule in src-tauri/CLAUDE.md).
| impl Default for InputArbiter { | ||
| fn default() -> Self { | ||
| Self::new(Duration::from_millis(50)) | ||
| } | ||
| } |
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Maintainability: Centralize default configuration values
According to the general rules, default configuration values should be centralized as public constants within their specific implementation modules to avoid redundancy and maintain consistency across the codebase.
Let's define a public constant for the default cooldown duration.
| impl Default for InputArbiter { | |
| fn default() -> Self { | |
| Self::new(Duration::from_millis(50)) | |
| } | |
| } | |
| pub const DEFAULT_COOLDOWN_MS: u64 = 50; | |
| impl Default for InputArbiter { | |
| fn default() -> Self { | |
| Self::new(Duration::from_millis(DEFAULT_COOLDOWN_MS)) | |
| } | |
| } |
References
- Centralize default configuration values as public constants within their specific implementation modules and reference them globally to avoid redundancy and maintain consistency across the codebase.
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Fixed in 92fd8b5. DEFAULT_COOLDOWN (500ms, Duration) already existed as the module's public constant; the real bug was that Default::default() hardcoded 50ms — a silent 10× discrepancy — and the AppState construction site duplicated the 500ms literal. Both now reference DEFAULT_COOLDOWN.
Hook execute_agent_internal into the AgentSessionRegistry via a RAII SessionHandle so every agent run appears in list_agent_sessions and can be targeted by focus_agent_session / cancel_agent_session commands. - Add next_session_color() round-robin picker (8 distinct colors) - Add SessionHandle: RAII guard that removes the session on drop and broadcasts agent-sessions-updated so the switcher UI drops the row on any exit path (success, error, panic unwind) - Add broadcast_sessions_updated() helper for callers without AppState - Wire execute_agent_internal to create + track a session per run Sessions today are 1:1 with agent runs because the execution queue still serializes; lifting that cap is separate work and unblocks true parallel execution. This delta makes the registry surface authoritative for the frontend switcher. Co-Authored-By: Paperclip <noreply@paperclip.ing>
… + agent_cursors) Main's 5e1fd19 added AgentCursorState cursor tracking; this branch adds the LAC-1432 session registry + input arbiter. Both coexist in AppState. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
- useAgentSessions hook: initial snapshot via list_agent_sessions, then event-driven sync from agent-sessions-updated (no polling) - AgentSessionSwitcher: pill strip above chat input showing each live session's cursor color, name, and current action; click focuses, X cancels one session without disturbing the rest - events.rs: strip curly braces from FOCUSED doc comment — the TS constants codegen silently dropped AGENT_SESSIONS_FOCUSED after it; regenerated constants now include both session events Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
…ed, optimize remove, DEFAULT_COOLDOWN - Replace `TokioMutex<Option<AgentSessionId>>` on `focused` with `std::sync::Mutex` — no async work is done while this lock is held, so the lighter-weight sync variant is appropriate and avoids unnecessary async scheduler overhead - `focused()` is now a sync fn (no `.await` needed at call sites) - Optimize `AgentSessionRegistry::remove()`: capture `next_id` from the sessions map before dropping it, eliminating the second `self.sessions.lock().await` acquire inside the focused critical section (was: drop sessions → lock focused → re-lock sessions) - Simplify auto-focus logic in `create()`: use a local bool instead of re-borrowing the guard after mutation - Add `InputArbiter::DEFAULT_COOLDOWN` public constant (500 ms) so callers share one canonical default instead of repeating the literal Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Gemini review — addressedAll four suggestions from the Gemini Code Assist review have been applied in commit
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Caution The consumer version of Gemini Code Assist on GitHub has been sunset. All code review activity has officially ceased. |
…ing, session cursors, roster UI, notifications Backend: - submit_query runs register in the session registry; merged global+session cancel channel gives per-session cancellation isolation; terminal states (finished/cancelled/failed) marked + lifecycle events emitted before RAII cleanup removes the row - Physical CGEvent input serialized through the InputArbiter: always-physical actions guard at dispatch, AX-attempt actions guard only in their physical fallback blocks so AX-grounded actions stay parallel across sessions - Cursor overlay keyed by session id + LAC-2830 identity palette (8 slots, round-robin with freed-slot reuse); SessionHandle::drop clears the cursor on every end path (complete, cancel, error, panic) - Escape/stop cancels only the FOCUSED session when parallel sessions exist; global cancel remains the legacy/headless fallback - Background (non-focused) sessions fire macOS notifications on completion/ failure via send_notification (respects user notification settings) Frontend (display-only): - AgentRosterStrip: identity dots below floating bar when 2+ agents run, status badges, completion-pulse/error-shake/needs-input-blink animations, +N overflow, tooltips, tablist a11y; bar window grows to fit - AgentSessionRows: named rows w/ current action + status icon in floating panel expanded mode; click to focus without pausing background sessions - Palette + lifecycle event constants generated from Rust (ui.rs/events.rs) Tests: session registry slot allocator + cancel isolation (Rust), 6 new AgentRosterStrip tests (Vitest). cargo check clean, tsc clean, 47/47 FE tests pass. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
…stry-and-input-arbiter * origin/main: style: rustfmt after clippy collapsible_match fix in lib.rs fix(clippy): resolve 5 clippy::collapsible_match/for_kv_map/sort_by warnings chore: add rustfmt and clippy components to rust-toolchain.toml ci: trigger CI run on current branch HEAD chore(fmt): reorder __CFArray import for rustfmt 1.97 compatibility chore: pin Rust toolchain to 1.97 via rust-toolchain.toml fix(scripts): make constants parser survive rustfmt line-wraps feat(browser): add 'property' option to browser_extract_content (LAC-3055) ci: gate rustfmt and clippy now that both pass style: apply rustfmt repo-wide style: clear all clippy warnings so the lint can be gated test: delete tests that verify nothing fix(browser): stop CDP cleanup destroying the user's browser; add live QA feat(browser): replace abandoned playwright crate with chromiumoxide (CDP) # Conflicts: # src-tauri/src/agent/mod.rs # src-tauri/src/agent/tools/anthropic_computer_use.rs # src-tauri/src/agents/desktop_agent.rs # src-tauri/src/agents/mod.rs # src-tauri/src/state.rs
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changed the title
Code review — LAC-1432 parallel background agent sessions (via LAC-2831)GitHub blocks approving/requesting-changes on one's own PR, so posting review as a comment. Verdict below: changes requested on Findings 1 & 2. Reviewed against the focus areas in LAC-2831: session isolation, input-arbiter safety, overlay lifecycle, deadlock risk, and CLAUDE.md compliance. The core wiring is solid — merged watch channel for cancellation, RAII SessionHandle cleanup, arbiter split between always-physical and AX-fallback paths, correct StdMutex vs TokioMutex choices, no 🔴 Finding 1 (request changes) — Setup-error paths skip session terminal lifecycle eventsFiles: The RAII When brain construction or tool registration fails mid-setup, the four early Suggested fix: Extract a helper ( 🔴 Finding 2 (request changes) —
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held_by() awaited the same TokioMutex the PhysicalInputGuard holds, so any observer asking "who holds the arbiter?" during a hold blocked forever — the two tests covering it hung >60s (they had never actually been run; earlier runs filtered on agents::session). Move the holder id into a separate std::sync::Mutex outside the input mutex: held_by() is now sync and safe during a hold; the guard clears the holder on drop. Tests updated to assert exactly the previously-deadlocking pattern plus holder cleared after drop. 4/4 arbiter tests pass in 0.04s. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Finding 1: setup-error paths now emit session terminal lifecycle events. Extracted finish_session_terminal_state() helper; all four early return-Err sites in execute_agent_internal (computer-use registration and brain init failures) call it with Failed before returning, so the roster row gets its error animation and background sessions notify instead of silently vanishing. Happy path uses the same helper. Finding 2: filed LAC-3073 and added TODO breadcrumb at the session_id: None call site in DesktopAgent — the SpecializedAgent path has no session registration, and the shared instance must not store one. Finding 3: stop coordinator only clears the global is-executing flag when no other session remains, so cancelling the focused session won't switch off execution UI for background agents once the queue cap lifts. Finding 4: registry construction comment now spells out the 12-cap vs 8-color-slot relationship and the accepted collision behavior. Finding 5: mark_terminal() returns the focus flag it read, so the notification gate and emitted snapshot derive from one read (no TOCTOU). Also: clippy cleanups in session.rs (Default for AgentSessionId, sort_by_key, is_empty alongside len). Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Review findings addressed — commit
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Re-review of commit 89de83bb — LGTM ✅ (posting as comment; GitHub blocks self-approval)
All five findings from the previous review are properly addressed. Verification below.
Finding 1 (blocking) — Setup-error terminal events ✅
finish_session_terminal_state() extracted in anthropic.rs:417. Called at all four outer-function early-return sites (setup failures for computer-use registration and brain init, both single-agent and specialist modes) with AgentSessionStatus::Failed, and by the happy path with the appropriate variant. Two remaining return Err(err_msg) sites I audited (anthropic.rs:767, 1075) are inside nested async move tool-executor closures for get_or_init_browser_controller() — those bubble into the tool-call loop, not out of execute_agent_internal, so correctly excluded. The helper's Option<&SessionHandle> signature means the CLI/headless path (no registered session) safely no-ops.
Finding 2 (blocking) — DesktopAgent session_id: None ✅
TODO(LAC-3073) breadcrumb at desktop_agent.rs:51 with a clear rationale (SpecializedAgent path not wired through registry, shared instance can't store a session id). LAC-3073 confirmed filed as child of LAC-1432, status todo. Deferral is acceptable per prior alignment.
Finding 3 (advisory) — Stop-coordinator global-flag clobber ✅
Gate at stop_coordinator.rs:235: if !cancelled_focused || len <= 1 { mark_finished }. Correct semantics — when the focused session is cancelled and background sessions remain (post-queue-cap-lift), the flag stays set so background-session UI keeps rendering; on the legacy !cancelled_focused fallback, signal_cancel() already targets all sessions so clearing the flag is right. Comment accurately documents the invariant.
Finding 4 (advisory) — 12-cap vs 8-palette collision ✅
Registry-construction comment in state.rs:432 explicitly notes sessions 9–12 wrap into the 8-slot palette per LAC-2830.
Finding 5 (advisory) — Focus TOCTOU ✅
mark_terminal() now returns the focus flag it read (session.rs:496); the notification gate in finish_session_terminal_state uses that return value. Single read, no disagreement possible between the emitted snapshot and the notification gate.
Verification
- ✅ Session tests: 6/6 passing (
agents::session::tests::*) - ✅ Arbiter tests: 4/4 passing (
agent::input_arbiter::tests::*) - ✅ CI: Frontend, claude-review, CodeQL all green
- ✅ LAC-3073 filed and linked as child of LAC-1432
Ready to merge — handing off to GitHub Engineer via LAC-2831 SDLC pipeline.
…OOLDOWN (500ms) Gemini review comment on PR #474: centralize the cooldown default. Default::default() hardcoded 50ms while DEFAULT_COOLDOWN and the AppState construction site both used 500ms — a silent 10x discrepancy if Default were ever used. Both sites now reference DEFAULT_COOLDOWN. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
…:remove Gemini review comment on PR #474: between releasing the sessions lock and updating focus, a concurrent remove() could delete the captured next-focus candidate, leaving focus pointing at a dead session. Reassign focus while still holding the sessions lock; the focused std mutex is held only for a brief no-await block, so lock ordering stays safe (no site holds focused while acquiring sessions). Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
…ission Resolves LAC-2832 criterion 5b: the NeedsInput variant and NEEDS_INPUT event were scaffolded end-to-end on the frontend but never reachable from the backend. - AgentSessionRegistry::begin_needs_input/end_needs_input with compare-and-set transitions (Running -> NeedsInput -> Running) so a cancellation landing mid-approval-wait is never clobbered - DefaultAgentRunner::check_batch_approval flips the session row while a risky tool batch awaits approval, emits agent-session-needs-input, rebroadcasts the session list, and notifies when the session is running unfocused in the background - Runner carries session_id via with_session_id(), wired at both top-level construction sites in anthropic.rs - 4 new unit tests covering transition, background-unfocused snapshot, cancellation guard, and Running-only precondition Implementation by Founding Engineer (run 9ff49924); verified and committed by CTO: cargo check clean, 10/10 session tests pass, TS constants codegen unchanged. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Re-review requested — head
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Correction to the comment above: PR #474 was already approved by the Code Reviewer at 21:59Z (re-review of |
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Re-review — LGTM ✅ (posted as comment: GitHub blocks self-approve; approval recorded on Paperclip LAC-2831)
Head: 9635a9fc (fmt-only after 7d5eaeff). All five findings from the prior round are addressed, verified against source.
Verified fixes
🔴 Finding 1 — Terminal-state emission on setup-error paths (89de83bb).
finish_session_terminal_state() helper at src-tauri/src/anthropic.rs:417 is called from all four setup-error return Err sites — single-agent computer-use (825), single-agent brain init (941), orchestrator computer-use (1029), orchestrator brain init (1226) — plus the happy path (1306). Single source of truth for the discrete lifecycle event + background notification, with focus read exactly once inside mark_terminal.
🔴 Finding 2 — TODO breadcrumb for orchestrated DesktopAgent (89de83bb).
src-tauri/src/agents/desktop_agent.rs:55-60 explains the SpecializedAgent path is unwired from AgentSessionRegistry, that this instance is shared so it must not store a per-run id, and the concrete consequence (roster current_action doesn't tick during orchestrated DesktopAgent runs; input arbitration unaffected). Tracked as LAC-3073.
🟡 Finding 3 — Stop coordinator preserves is-executing for background sessions (89de83bb).
stop_coordinator.rs:227-237 gates mark_agent_execution_finished() on !cancelled_focused || len <= 1, with a comment tying it to the LAC-1432 cap lift. The cancelled session's runner clears the flag on its own tear-down.
🟡 Finding 4 — 12-cap vs 8-color-slot mismatch documented (89de83bb).
state.rs:433-446 spells out that parallel cap 12 mirrors orchestrator max_parallel_tasks, deliberately exceeds the 8-slot SESSION_COLOR_SLOTS palette, and that sessions 9-12 wrap to reuse colors of 1-4 — accepted visual collision (mod-wrap in color_for_slot).
🟡 Finding 5 — mark_terminal returns focus flag it read (89de83bb).
session.rs:530 takes focus once, uses it to build the snapshot, and returns it; the notification gate in finish_session_terminal_state uses the returned value rather than re-reading is_focused(). Closes the TOCTOU between snapshot and gate.
Also verified since last review
92fd8b53—InputArbiter::default()usesDEFAULT_COOLDOWN(500 ms) atinput_arbiter.rs:124. Was 50 ms — silently permitted 10× the coordinated cadence.c52a00b6—AgentSessionRegistry::remove()atsession.rs:340-360holds the sessions map lock while reassigning focus, so a concurrentremove()cannot delete the replacement focus candidate between thekeys().next()read and the focus write.focusedis a std mutex held only for the reassignment block, no.awaitinside — no deadlock risk.7d5eaeff/9635a9fc— NeedsInput end-to-end:AgentSessionStatus::NeedsInput+set_status_if(expected, next)atsession.rs:231— CAS underTokioMutexso aCancellingstatus landing mid-wait is never overwritten.begin_needs_input/end_needs_inputare the only public surface; both go through the CAS.end_needs_inputbroadcasts.agent_runner.rs:543-582— approval-wait marks needs-input and clears on both exit paths (cancellation at 557, normal at 581), same focus-gate as terminal notifications (unfocused ⇒ notify).- Constant
agent_sessions::NEEDS_INPUTwired atconstants/events.rs:59. - 4 new tests:
needs_input_transition_and_guarded_restore,needs_input_reports_background_session_as_unfocused,needs_input_restore_does_not_clobber_cancellation,begin_needs_input_requires_running_session.
Verification I ran
- Read-through of anthropic.rs, session.rs, agent_runner.rs, stop_coordinator.rs, input_arbiter.rs, state.rs, desktop_agent.rs at head.
cargo test --package juno --lib agents::sessionlocally: 10/10 pass.- Frontend build, CodeQL, claude-review already pass. Rust CI still in progress at review time — gate the merge on it going green.
- No
unwrap/expectregressions in production paths; the only hits are in#[tokio::test]blocks (permitted by CLAUDE.md).
Approving as reviewer. Hand off to GitHub Engineer to merge once Rust CI is green.
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feat(LAC-1432): parallel background agent sessions — registry wiring, input arbiter, per-session cursors, roster UI, notifications
Closes the implementation phase of LAC-1432 via LAC-3059. Builds on the registry + arbiter scaffolding already on this branch.
What this PR does
Backend (Rust)
1.
submit_querywired through the session registry (anthropic.rs)AgentSession(id, identity color slot, status) and emitsagent-session-started.Finished/Cancelled/Failed) are marked on the session before the RAIISessionHandleremoves it, emittingagent-session-completed/cancelled/failed.2. Physical input routed through the
InputArbiter(anthropic_computer_use.rs)middle_click,triple_click,left_click_drag,mouse_move,left_mouse_down/up,key,hold_key,scroll) acquire the arbiter guard before dispatch.left_click,right_click,double_click,type) acquire the guard only inside their physical fallback blocks — AX-grounded actions stay fully parallel across sessions (the parallelism moat).3. Per-session cursor identity + guaranteed cleanup
SessionToolContextflows fromexecute_agent_internal→BrainFactory::register_computer_use_tools_for_session→ the computer-tool closure.SessionHandle::dropclears the session's cursor (state map +agent-cursor-removeevent) on every end path — complete, cancel, error, panic unwind.cursor-overlay-{session_id}windows. Since LAC-1920 landed, the desktop overlay is a single full-screen click-through window with 8 per-agent cursor slots driven byagent-cursor-updateevents. Keying that existing system by session id delivers the same outcome (distinct per-session cursors, destroyed on every end path) without spawning up to 8 extra transparent always-on-top windows and duplicating the macOS window-level setup. Happy to revisit if reviewers prefer literal per-session windows.4. Identity palette per LAC-2830 spec §2
#3B82F6…#EC4899) defined once inconstants/ui.rs, generated to the frontend (UI.AGENT_SESSION_COLORS_SLOT_*).5. Lifecycle events + macOS notifications
agent-session-started/completed/cancelled/failed/needs-input(+ existingagent-sessions-updatedfull-snapshot channel, which doubles as action-update).send_notificationcommand, which respects the user's notification settings (system/toast/both/disabled). Cancellations never notify (user-initiated). Focused sessions never notify (outcome already on screen).needs_inputstatus + event are defined but not yet triggered — no backend ask-user mechanism exists today; documented for the follow-up that adds one.6. Cancellation isolation + escape key
stop_all_operations(escape path) now cancels only the focused session when the registry has live sessions; global cancel remains the fallback for legacy/headless paths.Frontend (TS — display-only)
AgentRosterStrip(new): dot strip below the floating bar when ≥2 sessions run. Identity-colored dots, status badge overlay, focused ring,+Noverflow, hover tooltips (name + current action),role=taba11y. Animations per spec §6/§8: completion pulse (green), error shake (red), needs-input blink (white/agent color).FloatingBar: renders the strip and grows the window height when it's visible.AgentSessionRows(new): named rows (color dot, name, current action, status icon, summary footer) in the floating panel's expanded mode; click row → focus. Panel + window height grow with the list, capped with scroll.focus_agent_session— focus is metadata only; background sessions are never paused.current_actionstreams from the backend per computer-use action (get_descriptive_tool_name), so rows/tooltips show e.g. "Click at (512, 384)".Tests
AgentRosterStriptests (render threshold, dot-per-session, focus click, aria-selected, +N overflow, notification animation classes) + updated switcher tests. 47/47 pass.cargo checkclean;npx tsc --noEmitclean.Known follow-ups (not in this PR)
agent_namethreaded intoAgentCursorState.needs_inputtrigger once an ask-user mechanism exists.🤖 Generated with Claude Code