fix: map internal worker terminal lifecycles

crates/session-store/tests/session_test.rs

@@ -102,7 +102,7 @@ async fn run_and_persist(
     session_id: session_store::SessionId,
     segment_id: session_store::SegmentId,
     input: &str,
-) -> (Engine<MockLlmClient>, agen::EngineResult) {
+) -> (Engine<MockLlmClient>, agen::EngineRunExit) {
     // Mirror Worker's run-entry contract: log the user input as segments
     // before the worker pushes its flattened user_message; save_delta
     // skips the resulting user_message item to avoid double-write.
@@ -125,31 +125,49 @@ async fn run_and_persist(
     session_store::save_turn_end(store, session_id, segment_id, worker.turn_count()).unwrap();
 
     match &result {
-        Ok(r) => {
+        agen::EngineRunExit::Finished
+        | agen::EngineRunExit::Paused
+        | agen::EngineRunExit::Yielded => {
+            let (legacy_result, interrupted) = match &result {
+                agen::EngineRunExit::Finished => (agen::EngineResult::Finished, false),
+                agen::EngineRunExit::Paused => (agen::EngineResult::Paused, true),
+                agen::EngineRunExit::Yielded => (agen::EngineResult::Yielded, true),
+                agen::EngineRunExit::Interrupted(_) => unreachable!(),
+            };
             session_store::save_run_completed(
                 store,
                 session_id,
                 segment_id,
-                r.clone(),
+                legacy_result,
-                worker.last_run_interrupted(),
+                interrupted,
                 worker.active_run_turn_count(),
             )
             .unwrap();
         }
-        Err(e) => {
+        agen::EngineRunExit::Interrupted(agen::StopReason::LimitReached) => {
+            session_store::save_run_completed(
+                store,
+                session_id,
+                segment_id,
+                agen::EngineResult::LimitReached,
+                false,
+                worker.active_run_turn_count(),
+            )
+            .unwrap();
+        }
+        agen::EngineRunExit::Interrupted(reason) => {
             session_store::save_run_errored(
                 store,
                 session_id,
                 segment_id,
-                e.to_string(),
+                format!("{reason:?}"),
-                worker.last_run_interrupted(),
+                true,
             )
             .unwrap();
         }
     }
 
-    let r = result.unwrap();
+    (worker, result)
-    (worker, r)
 }
 
 // =============================================================================
@@ -292,7 +310,7 @@ async fn session_resume_after_pause() {
     .unwrap();
 
     let (_worker, result) = run_and_persist(worker, &store, sid, segid, "Weather?").await;
-    assert!(matches!(result, agen::EngineResult::Paused));
+    assert!(matches!(result, agen::EngineRunExit::Paused));
 
     // Check RunCompleted is Paused
     let entries = store.read_all(sid, segid).unwrap();

crates/worker/examples/worker_cli.rs

@@ -66,6 +66,7 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
         WorkerRunResult::Finished => println!("(finished)"),
         WorkerRunResult::Paused => println!("(paused)"),
         WorkerRunResult::LimitReached => println!("(turn limit reached)"),
+        WorkerRunResult::Interrupted { message, .. } => println!("(interrupted: {message})"),
         WorkerRunResult::RolledBack => println!("(empty turn rolled back)"),
     }
 

crates/worker/src/controller.rs

@@ -1650,13 +1650,13 @@ where
                             WorkerRunResult::Paused => (WorkerStatus::Paused, RunResult::Paused),
                             WorkerRunResult::LimitReached => (WorkerStatus::Idle, RunResult::LimitReached),
                             WorkerRunResult::RolledBack => (WorkerStatus::Idle, RunResult::RolledBack),
-                            WorkerRunResult::Interrupted(_message) if pause_requested => {
+                            WorkerRunResult::Interrupted { .. } if pause_requested => {
                                 let _ = event_tx.send(Event::RunEnd { result: RunResult::Paused });
                                 return (WorkerStatus::Paused, shutdown_requested);
                             }
-                            WorkerRunResult::Interrupted(message) => {
+                            WorkerRunResult::Interrupted { code, message } => {
                                 let _ = event_tx.send(Event::Error {
-                                    code: ErrorCode::Internal,
+                                    code,
                                     message: message.clone(),
                                 });
                                 if parent_originated {

crates/worker/src/internal_worker.rs

@@ -199,10 +199,12 @@ where
     on_cancel_sender(worker.engine_mut().cancel_sender());
 
     match worker.run_text(&input).await {
-        Ok(WorkerRunResult::Interrupted(message)) => Err(InternalWorkerError {
+        Ok(lifecycle @ WorkerRunResult::Finished)
-            source: WorkerError::Engine(EngineError::Aborted(message)),
+        | Ok(lifecycle @ WorkerRunResult::Paused)
+        | Ok(lifecycle @ WorkerRunResult::RolledBack) => Ok(InternalWorkerResult {
             usage: last_usage.lock().ok().and_then(|slot| slot.clone()),
             identity,
+            lifecycle,
             history_entries: store.entries_count(session_id, segment_id),
         }),
         Ok(WorkerRunResult::LimitReached) => Err(InternalWorkerError {
@@ -213,10 +215,10 @@ where
             identity,
             history_entries: store.entries_count(session_id, segment_id),
         }),
-        Ok(lifecycle) => Ok(InternalWorkerResult {
+        Ok(WorkerRunResult::Interrupted { message, .. }) => Err(InternalWorkerError {
+            source: WorkerError::Engine(EngineError::Aborted(message)),
             usage: last_usage.lock().ok().and_then(|slot| slot.clone()),
             identity,
-            lifecycle,
             history_entries: store.entries_count(session_id, segment_id),
         }),
         Err(source) => Err(InternalWorkerError {
@@ -246,6 +248,7 @@ impl Default for InternalWorkerVisibility {
 pub(crate) enum InternalWorkerSessionStatus {
     Idle,
     Running,
+    Paused,
     Stopping,
     Stopped,
     Failed,
@@ -256,9 +259,10 @@ impl InternalWorkerSessionStatus {
         match self {
             Self::Idle => 0,
             Self::Running => 1,
-            Self::Stopping => 2,
+            Self::Paused => 2,
-            Self::Stopped => 3,
+            Self::Stopping => 3,
-            Self::Failed => 4,
+            Self::Stopped => 4,
+            Self::Failed => 5,
         }
     }
 
@@ -266,13 +270,35 @@ impl InternalWorkerSessionStatus {
         match value {
             0 => Self::Idle,
             1 => Self::Running,
-            2 => Self::Stopping,
+            2 => Self::Paused,
-            3 => Self::Stopped,
+            3 => Self::Stopping,
+            4 => Self::Stopped,
             _ => Self::Failed,
         }
     }
 }
 
+fn classify_internal_turn_result(
+    result: Result<WorkerRunResult, WorkerError>,
+) -> (InternalWorkerSessionStatus, Option<String>) {
+    match result {
+        Ok(WorkerRunResult::Finished) => (InternalWorkerSessionStatus::Idle, None),
+        Ok(WorkerRunResult::Paused) => (InternalWorkerSessionStatus::Paused, None),
+        Ok(WorkerRunResult::LimitReached) => (
+            InternalWorkerSessionStatus::Stopped,
+            Some("internal Worker reached its turn limit".to_string()),
+        ),
+        Ok(WorkerRunResult::Interrupted { message, .. }) => {
+            (InternalWorkerSessionStatus::Stopped, Some(message))
+        }
+        Ok(WorkerRunResult::RolledBack) => (
+            InternalWorkerSessionStatus::Stopped,
+            Some("internal Worker run was cancelled before AI output".to_string()),
+        ),
+        Err(error) => (InternalWorkerSessionStatus::Failed, Some(error.to_string())),
+    }
+}
+
 #[derive(Debug, thiserror::Error)]
 pub(crate) enum InternalWorkerSessionError {
     #[error("failed to build internal Worker session: {message}")]
@@ -367,6 +393,7 @@ impl InternalWorkerSessionHandle {
             entries,
             status: match self.status() {
                 InternalWorkerSessionStatus::Running => WorkerStatus::Running,
+                InternalWorkerSessionStatus::Paused => WorkerStatus::Paused,
                 InternalWorkerSessionStatus::Idle => WorkerStatus::Idle,
                 InternalWorkerSessionStatus::Stopping
                 | InternalWorkerSessionStatus::Stopped
@@ -402,6 +429,7 @@ impl InternalWorkerSessionHandle {
             .map_err(
                 |current| match InternalWorkerSessionStatus::decode(current) {
                     InternalWorkerSessionStatus::Running
+                    | InternalWorkerSessionStatus::Paused
                     | InternalWorkerSessionStatus::Stopping => InternalWorkerSessionError::Busy,
                     InternalWorkerSessionStatus::Stopped | InternalWorkerSessionStatus::Failed => {
                         InternalWorkerSessionError::Stopped
@@ -747,21 +775,7 @@ pub(crate) async fn prepare_internal_worker_session(
                     loop {
                         tokio::select! {
                             result = &mut run => {
-                                let (turn_status, error) = match result {
+                                let (turn_status, error) = classify_internal_turn_result(result);
-                                    Ok(WorkerRunResult::Interrupted(message)) => (
-                                        InternalWorkerSessionStatus::Stopped,
-                                        Some(message),
-                                    ),
-                                    Ok(WorkerRunResult::LimitReached) => (
-                                        InternalWorkerSessionStatus::Stopped,
-                                        Some("internal Worker reached its turn limit".to_string()),
-                                    ),
-                                    Ok(_) => (InternalWorkerSessionStatus::Idle, None),
-                                    Err(error) => (
-                                        InternalWorkerSessionStatus::Failed,
-                                        Some(error.to_string()),
-                                    ),
-                                };
                                 actor_in_flight.clear();
                                 status.store(turn_status.encode(), std::sync::atomic::Ordering::Release);
                                 if let Some(message) = error {
@@ -771,10 +785,15 @@ pub(crate) async fn prepare_internal_worker_session(
                                         message,
                                     });
                                 }
-                                let protocol_status = if turn_status == InternalWorkerSessionStatus::Idle {
+                                let protocol_status = match turn_status {
-                                    WorkerStatus::Idle
+                                    InternalWorkerSessionStatus::Idle => WorkerStatus::Idle,
-                                } else {
+                                    InternalWorkerSessionStatus::Paused => WorkerStatus::Paused,
-                                    WorkerStatus::Stopped
+                                    InternalWorkerSessionStatus::Stopped
+                                    | InternalWorkerSessionStatus::Failed => WorkerStatus::Stopped,
+                                    InternalWorkerSessionStatus::Running
+                                    | InternalWorkerSessionStatus::Stopping => {
+                                        unreachable!("run completion cannot remain active")
+                                    }
                                 };
                                 let _ = event_tx.send(Event::Status {
                                     status: protocol_status,
@@ -1261,6 +1280,52 @@ permission = "write"
         assert_eq!(result.identity.kind, "test");
     }
 
+    #[test]
+    fn internal_turn_result_mapping_is_exhaustive() {
+        let cases = [
+            (
+                WorkerRunResult::Finished,
+                InternalWorkerSessionStatus::Idle,
+                false,
+            ),
+            (
+                WorkerRunResult::Paused,
+                InternalWorkerSessionStatus::Paused,
+                false,
+            ),
+            (
+                WorkerRunResult::LimitReached,
+                InternalWorkerSessionStatus::Stopped,
+                true,
+            ),
+            (
+                WorkerRunResult::Interrupted {
+                    code: protocol::ErrorCode::Internal,
+                    message: "cancelled".to_string(),
+                },
+                InternalWorkerSessionStatus::Stopped,
+                true,
+            ),
+            (
+                WorkerRunResult::RolledBack,
+                InternalWorkerSessionStatus::Stopped,
+                true,
+            ),
+        ];
+
+        for (result, expected_status, expects_error) in cases {
+            let (status, error) = classify_internal_turn_result(Ok(result));
+            assert_eq!(status, expected_status);
+            assert_eq!(error.is_some(), expects_error);
+        }
+
+        let (status, error) = classify_internal_turn_result(Err(WorkerError::Engine(
+            EngineError::Aborted("fatal".to_string()),
+        )));
+        assert_eq!(status, InternalWorkerSessionStatus::Failed);
+        assert!(error.is_some_and(|message| message.contains("fatal")));
+    }
+
     #[tokio::test]
     async fn fatal_internal_run_transitions_to_stopped_protocol_status() {
         let calls = Arc::new(AtomicUsize::new(0));

crates/worker/src/worker.rs

@@ -77,8 +77,8 @@ use crate::skill::{SkillActivationResponse, SkillClientError};
 #[cfg(test)]
 use async_trait::async_trait;
 use protocol::{
-    AlertLevel, AlertSource, CompactionLifecycle, CompactionLifecycleState, Event, RewindSummary,
+    AlertLevel, AlertSource, CompactionLifecycle, CompactionLifecycleState, ErrorCode, Event,
-    RewindTarget, RewindTargetId, Segment,
+    RewindSummary, RewindTarget, RewindTargetId, Segment,
 };
 use tokio::net::UnixStream;
 use tokio::sync::broadcast;
@@ -2964,7 +2964,10 @@ impl<C: LlmClient, St: Store> Worker<C, St> {
             }
             EngineRunExit::Interrupted(reason) => {
                 self.last_run_interrupted = true;
-                Ok(WorkerRunResult::Interrupted(stop_reason_message(&reason)))
+                Ok(WorkerRunResult::Interrupted {
+                    code: stop_reason_error_code(&reason),
+                    message: stop_reason_message(&reason),
+                })
             }
             EngineRunExit::Yielded => unreachable!("yielded handled above"),
         }
@@ -4512,7 +4515,7 @@ impl<C: LlmClient, St: Store> Worker<C, St> {
 fn extract_internal_worker_lifecycle_error(lifecycle: &WorkerRunResult) -> Option<WorkerError> {
     match lifecycle {
         WorkerRunResult::RolledBack => Some(WorkerError::Engine(EngineError::Cancelled)),
-        WorkerRunResult::Interrupted(message) => {
+        WorkerRunResult::Interrupted { message, .. } => {
             Some(WorkerError::Engine(EngineError::Aborted(message.clone())))
         }
         WorkerRunResult::Finished | WorkerRunResult::Paused | WorkerRunResult::LimitReached => None,
@@ -5521,6 +5524,23 @@ fn restore_manifest_from_worker_metadata_snapshot(
     }
 }
 
+fn stop_reason_error_code(reason: &StopReason) -> ErrorCode {
+    match reason {
+        StopReason::ContextWindowExceeded | StopReason::Unexpected(EngineError::Client(_)) => {
+            ErrorCode::ProviderError
+        }
+        StopReason::Unexpected(EngineError::Tool(_)) => ErrorCode::ToolError,
+        StopReason::LimitReached
+        | StopReason::Cancelled
+        | StopReason::Unexpected(
+            EngineError::Aborted(_)
+            | EngineError::Cancelled
+            | EngineError::ConfigWarnings(_)
+            | EngineError::HistoryAppend(_),
+        ) => ErrorCode::Internal,
+    }
+}
+
 fn stop_reason_message(reason: &StopReason) -> String {
     match reason {
         StopReason::LimitReached => "engine turn limit reached".to_string(),
@@ -5540,7 +5560,7 @@ pub enum WorkerRunResult {
     /// The worker reached its configured max_turns limit.
     LimitReached,
     /// The run was interrupted by a known or unexpected terminal cause.
-    Interrupted(String),
+    Interrupted { code: ErrorCode, message: String },
     /// The submit-time user turn was rolled back because no AI output was materialized.
     RolledBack,
 }

web/workspace/src/lib/workspace/sidebar/WorkersNavSection.svelte

@@ -5,7 +5,7 @@
     workspaceWorkersStore,
     type SidebarWorker,
   } from './worker-subscription';
-  import { canShowWorkerInSidebar } from './workers';
+  import { canShowWorkerInSidebar, sidebarWorkerActivity } from './workers';
 
   const COLLAPSED_WORKER_COUNT = 6;
 
@@ -69,6 +69,7 @@
     <ul class="nav-list" aria-label="Workers">
       {#each visibleWorkers as worker (`${worker.runtime_id}:${worker.worker_id}`)}
         {@const href = workerConsoleHref(worker, workspaceId)}
+        {@const activity = sidebarWorkerActivity(worker)}
         <li>
           <a
             href={href}
@@ -77,11 +78,11 @@
             aria-current={currentPath === href ? 'page' : undefined}
           >
             <span class="worker-status-indicator">
-              {#if worker.state === 'running'}
+              {#if activity === 'worker-running'}
                 <span class="worker-status-spinner"><Spinner label="Running" /></span>
-              {:else if worker.has_running_internal_workers}
+              {:else if activity === 'subworker-running'}
                 <span class="worker-status-spinner is-subworker"><Spinner label="SubWorker running" /></span>
-              {:else if worker.state === 'idle'}
+              {:else if activity === 'idle'}
                 <span class="worker-status-dot" aria-label="Idle"></span>
               {/if}
             </span>

web/workspace/src/lib/workspace/sidebar/worker-subscription.test.ts

@@ -14,13 +14,18 @@ declare const Deno: {
   test(name: string, fn: () => void | Promise<void>): void;
 };
 
-function worker(runtimeId: string, workerId: string, revision: number): SubscriptionWorker {
+function worker(
+  runtimeId: string,
+  workerId: string,
+  revision: number,
+  hasRunningInternalWorkers = false,
+): SubscriptionWorker {
   return {
     worker_id: workerId,
     runtime_id: runtimeId,
     subject_revision: revision,
     state: 'idle',
-    has_running_internal_workers: false,
+    has_running_internal_workers: hasRunningInternalWorkers,
     workspace_id: 'workspace-test',
     display_name: null,
     profile: null,
@@ -88,3 +93,28 @@ Deno.test('workspace Worker reducer ignores stale events and removes composite s
   assertEquals(projection.workers.size, 0);
   assertEquals(projection.revisions.get('runtime-a:1'), 4);
 });
+
+Deno.test('fatal child stop replaces the running-child sidebar projection', () => {
+  const projection = createWorkspaceWorkersProjection();
+  projection.workers.set('runtime-a:1', worker('runtime-a', '1', 1, true));
+  projection.revisions.set('runtime-a:1', 1);
+
+  applyWorkspaceWorkersFrame(projection, {
+    protocol_version: 1,
+    frame: 'event',
+    message: {
+      event: 'event',
+      data: {
+        subscription_id: 'subscription-1',
+        subject_revision: 2,
+        payload: {
+          event: 'worker_upserted',
+          data: { worker: worker('runtime-a', '1', 2, false) },
+        },
+      },
+    },
+  });
+
+  assertEquals(projection.workers.get('runtime-a:1')?.has_running_internal_workers, false);
+  assertEquals(projection.revisions.get('runtime-a:1'), 2);
+});

web/workspace/src/lib/workspace/sidebar/workers.test.ts

@@ -2,6 +2,7 @@ import {
   canOpenWorkerConsole,
   canShowWorkerInSidebar,
   compareWorkersForSidebar,
+  sidebarWorkerActivity,
 } from "./workers.ts";
 import type { Worker } from "./types.ts";
 
@@ -77,3 +78,21 @@ Deno.test("sidebar workers sort running then idle then stopped", () => {
   workers.sort(compareWorkersForSidebar);
   assertEquals(workers.map((candidate) => candidate.worker_id).join(","), "2,1,4,3");
 });
+
+Deno.test("fatal child stop clears the sidebar SubWorker spinner activity", () => {
+  const parent = { state: "idle", has_running_internal_workers: true };
+  assertEquals(sidebarWorkerActivity(parent), "subworker-running");
+
+  parent.has_running_internal_workers = false;
+  assertEquals(sidebarWorkerActivity(parent), "idle");
+});
+
+Deno.test("stopped parents do not fall back to the idle indicator", () => {
+  assertEquals(
+    sidebarWorkerActivity({
+      state: "stopped",
+      has_running_internal_workers: false,
+    }),
+    "none",
+  );
+});

web/workspace/src/lib/workspace/sidebar/workers.ts

@@ -1,5 +1,24 @@
 import type { Worker } from './types';
 
+export type SidebarWorkerActivity =
+  | 'worker-running'
+  | 'subworker-running'
+  | 'idle'
+  | 'none';
+
+type WorkerActivitySource = Pick<Worker, 'state'> & {
+  has_running_internal_workers: boolean;
+};
+
+export function sidebarWorkerActivity(
+  worker: WorkerActivitySource,
+): SidebarWorkerActivity {
+  if (worker.state === 'running') return 'worker-running';
+  if (worker.has_running_internal_workers) return 'subworker-running';
+  if (worker.state === 'idle') return 'idle';
+  return 'none';
+}
+
 export function canShowWorkerInSidebar(worker: Worker): boolean {
   return worker.implementation.kind !== 'backend_worker_registry';
 }