diff --git a/apps/backend/internal/agent/runtime/lifecycle/workspace_sources_reconcile_test.go b/apps/backend/internal/agent/runtime/lifecycle/workspace_sources_reconcile_test.go
index d56593fb3e..f6c03d2740 100644
--- a/apps/backend/internal/agent/runtime/lifecycle/workspace_sources_reconcile_test.go
+++ b/apps/backend/internal/agent/runtime/lifecycle/workspace_sources_reconcile_test.go
@@ -22,8 +22,19 @@ func TestReconcileWorkspaceSources_RejectsMissingFolderTarget(t *testing.T) {
 	}
 }
 
+// canonicalTempDir resolves symlinks in t.TempDir() so tests hand production
+// code a canonical owned control root (macOS /var -> /private/var); no-op on Linux.
+func canonicalTempDir(t *testing.T) string {
+	t.Helper()
+	d, err := filepath.EvalSymlinks(t.TempDir())
+	if err != nil {
+		t.Fatalf("EvalSymlinks: %v", err)
+	}
+	return d
+}
+
 func TestReconcileWorkspaceRepositories_RecreatesMissingOwnedLink(t *testing.T) {
-	root, source := t.TempDir(), t.TempDir()
+	root, source := canonicalTempDir(t), t.TempDir()
 	writeMarker(t, source)
 	if err := reconcileWorkspaceRepositories(root, []WorkspaceRepositorySpec{{RepoName: "api", RepositoryPath: source}}, nil); err != nil {
 		t.Fatalf("reconcileWorkspaceRepositories: %v", err)
@@ -77,7 +88,7 @@ func TestReconcileWorkspaceRepositories_SkipsRepositoryThatIsWorkspaceRoot(t *te
 // contract though — the user has to learn the entry is there — so the warning
 // and its structured entry path are asserted too.
 func TestReconcileWorkspaceRepositories_PreservesAndReportsPreExistingSelfLink(t *testing.T) {
-	root := t.TempDir()
+	root := canonicalTempDir(t)
 	marker := writeMarker(t, root)
 	if _, err := worktree.CreateOwnedDirectoryLink(root, "api", root); err != nil {
 		t.Fatalf("seed self link: %v", err)
@@ -127,7 +138,7 @@ func TestReconcileWorkspaceRepositories_DoesNotWarnWithoutSelfLink(t *testing.T)
 
 // The guard is per spec, not a blanket skip: siblings still need their links.
 func TestReconcileWorkspaceRepositories_LinksSiblingWhenPrimaryIsWorkspaceRoot(t *testing.T) {
-	root, sibling := t.TempDir(), t.TempDir()
+	root, sibling := canonicalTempDir(t), t.TempDir()
 	writeMarker(t, sibling)
 
 	err := reconcileWorkspaceRepositories(root, []WorkspaceRepositorySpec{
@@ -231,7 +242,7 @@ func TestReconcileWorkspaceRepositories_RejectsTraversalRepoName(t *testing.T) {
 // where the first repository is a real sibling — so the guard must not degrade
 // into skipping index 0.
 func TestReconcileWorkspaceRepositories_LinksPrimaryWhenRootIsTaskDirectory(t *testing.T) {
-	root := filepath.Join(t.TempDir(), "tasks", "task-1")
+	root := filepath.Join(canonicalTempDir(t), "tasks", "task-1")
 	primary := t.TempDir()
 	writeMarker(t, primary)
 
diff --git a/apps/backend/internal/agentctl/server/api/workspace_materialize_test.go b/apps/backend/internal/agentctl/server/api/workspace_materialize_test.go
index b94bfaf5d2..0bb136f3f6 100644
--- a/apps/backend/internal/agentctl/server/api/workspace_materialize_test.go
+++ b/apps/backend/internal/agentctl/server/api/workspace_materialize_test.go
@@ -359,7 +359,7 @@ func TestWorkspaceRemoveMaterializedRepository_RejectsSymlinkedGitMetadata(t *te
 
 func TestWorkspaceRemoveMaterializedRepository_RestoresSwappedReplacement(t *testing.T) {
 	origin := createMaterializeOrigin(t)
-	workDir := t.TempDir()
+	workDir := canonicalTempDir(t)
 	destination := filepath.Join(workDir, "second-repo")
 	if _, err := materializeRepository(context.Background(), origin, destination, "main", ""); err != nil {
 		t.Fatal(err)
@@ -393,7 +393,7 @@ func TestWorkspaceRemoveMaterializedRepository_RestoresSwappedReplacement(t *tes
 
 func TestWorkspaceRemoveMaterializedRepository_RejectsPostQuarantineReplacement(t *testing.T) {
 	origin := createMaterializeOrigin(t)
-	workDir := t.TempDir()
+	workDir := canonicalTempDir(t)
 	destination := filepath.Join(workDir, "second-repo")
 	if _, err := materializeRepository(context.Background(), origin, destination, "main", ""); err != nil {
 		t.Fatal(err)
@@ -441,6 +441,16 @@ func TestWorkspaceRemoveMaterializedRepository_RejectsTraversal(t *testing.T) {
 	}
 }
 
+// canonicalTempDir resolves symlinks so expected paths match the canonical roots production computes (no-op on Linux).
+func canonicalTempDir(t *testing.T) string {
+	t.Helper()
+	d, err := filepath.EvalSymlinks(t.TempDir())
+	if err != nil {
+		t.Fatalf("EvalSymlinks: %v", err)
+	}
+	return d
+}
+
 func newMaterializeTestServer(t *testing.T, workDir string) *Server {
 	t.Helper()
 	log := newTestLogger()
diff --git a/apps/backend/internal/agentctl/server/process/workspace_git_cmd_test.go b/apps/backend/internal/agentctl/server/process/workspace_git_cmd_test.go
index 394e7f6d6d..1ba26de687 100644
--- a/apps/backend/internal/agentctl/server/process/workspace_git_cmd_test.go
+++ b/apps/backend/internal/agentctl/server/process/workspace_git_cmd_test.go
@@ -106,7 +106,11 @@ func TestRunGitOutput_PollingVariantReleasesThrottleOnTimeout(t *testing.T) {
 
 func TestWorkspaceGitAdmissionWaitDoesNotConsumeTimeout(t *testing.T) {
 	prev := gitCommandTimeout
-	gitCommandTimeout = 100 * time.Millisecond
+	// The execution budget must comfortably exceed a cold shell-shim start
+	// (slow on macOS), or the freshly-admitted command is SIGKILLed before it
+	// can print. The hold below is still longer than this budget, so the test
+	// still proves the queued command gets a fresh budget after admission.
+	gitCommandTimeout = 2 * time.Second
 	t.Cleanup(func() { gitCommandTimeout = prev })
 
 	restoreCap := subproc.Git().SetCapForTest(1)
@@ -132,8 +136,8 @@ func TestWorkspaceGitAdmissionWaitDoesNotConsumeTimeout(t *testing.T) {
 	}()
 	waitForAnyGitWaiter(t, 1)
 	// Hold the slot longer than the execution timeout. The queued command
-	// should still receive a fresh 100ms execution budget after release.
-	timer := time.NewTimer(150 * time.Millisecond)
+	// should still receive a fresh execution budget after release.
+	timer := time.NewTimer(2500 * time.Millisecond)
 	<-timer.C
 	hold()
 
@@ -142,7 +146,7 @@ func TestWorkspaceGitAdmissionWaitDoesNotConsumeTimeout(t *testing.T) {
 		if result.err != nil || string(result.out) != "ok" {
 			t.Fatalf("result = (%q, %v), want fast command after queued admission", result.out, result.err)
 		}
-	case <-time.After(time.Second):
+	case <-time.After(3 * time.Second):
 		t.Fatal("queued git command did not complete")
 	}
 }
diff --git a/apps/backend/internal/backendapp/adapters.go b/apps/backend/internal/backendapp/adapters.go
index 533ea12197..7186f56f0d 100644
--- a/apps/backend/internal/backendapp/adapters.go
+++ b/apps/backend/internal/backendapp/adapters.go
@@ -11,6 +11,7 @@ import (
 
 	"github.com/kandev/kandev/internal/agent/agents"
 	"github.com/kandev/kandev/internal/agent/registry"
+	runtimeapi "github.com/kandev/kandev/internal/agent/runtime"
 	"github.com/kandev/kandev/internal/agent/runtime/agentctl"
 	"github.com/kandev/kandev/internal/agent/runtime/lifecycle"
 	"github.com/kandev/kandev/internal/agentctl/types/streams"
@@ -322,8 +323,25 @@ func (a *lifecycleAdapter) StopAgent(ctx context.Context, agentInstanceID string
 }
 
 // StopAgentWithReason stops a running agent and propagates the stop reason to runtime teardown.
+// The lifecycle-tier not-found sentinel is normalized to the public runtime
+// sentinel at this seam so orchestrator consumers depend only on
+// runtimeapi.ErrNotFound and never import runtime/lifecycle.
 func (a *lifecycleAdapter) StopAgentWithReason(ctx context.Context, agentInstanceID string, reason string, force bool) error {
-	return a.mgr.StopAgentWithReason(ctx, agentInstanceID, reason, force)
+	return normalizeRuntimeStopError(a.mgr.StopAgentWithReason(ctx, agentInstanceID, reason, force))
+}
+
+// normalizeRuntimeStopError maps the backend lifecycle not-found sentinel onto
+// the public runtime not-found sentinel while preserving the original error for
+// diagnostics. Unrelated errors (and nil) pass through unchanged so a transient
+// runtime failure is never mistaken for an absent runtime.
+func normalizeRuntimeStopError(err error) error {
+	if err == nil {
+		return nil
+	}
+	if errors.Is(err, lifecycle.ErrExecutionNotFound) {
+		return errors.Join(runtimeapi.ErrNotFound, err)
+	}
+	return err
 }
 
 // RowLiveness classifies the liveness of the OS process backing an
diff --git a/apps/backend/internal/backendapp/adapters_test.go b/apps/backend/internal/backendapp/adapters_test.go
index d89094c324..a124433fc3 100644
--- a/apps/backend/internal/backendapp/adapters_test.go
+++ b/apps/backend/internal/backendapp/adapters_test.go
@@ -9,6 +9,8 @@ import (
 	"sync"
 	"testing"
 
+	runtimeapi "github.com/kandev/kandev/internal/agent/runtime"
+	"github.com/kandev/kandev/internal/agent/runtime/lifecycle"
 	"github.com/kandev/kandev/internal/common/logger"
 	githubsvc "github.com/kandev/kandev/internal/github"
 	"github.com/kandev/kandev/internal/repoclone"
@@ -223,7 +225,7 @@ func TestResolveForReviewRedetectsStoredMasterAfterClonePath(t *testing.T) {
 	if err != nil {
 		t.Fatalf("CreateWorkspace: %v", err)
 	}
-	basePath := t.TempDir()
+	basePath := canonicalTempDir(t)
 	cloner := repoclone.NewCloner(
 		repoclone.Config{BasePath: basePath}, repoclone.ProtocolHTTPS, "", newTestLogger(),
 	)
@@ -414,6 +416,30 @@ func TestWrapGitHubTaskIssueStoreError(t *testing.T) {
 	}
 }
 
+// TestNormalizeRuntimeStopError asserts the lifecycle adapter maps the backend
+// lifecycle not-found sentinel onto the public runtime not-found sentinel, so
+// orchestrator/reconciliation can depend only on runtimeapi.ErrNotFound and
+// never has to import runtime/lifecycle. Unrelated errors pass through unchanged.
+func TestNormalizeRuntimeStopError(t *testing.T) {
+	if got := normalizeRuntimeStopError(nil); got != nil {
+		t.Fatalf("normalizeRuntimeStopError(nil) = %v, want nil", got)
+	}
+
+	wrapped := fmt.Errorf("stop agent: %w", lifecycle.ErrExecutionNotFound)
+	got := normalizeRuntimeStopError(wrapped)
+	if !errors.Is(got, runtimeapi.ErrNotFound) {
+		t.Fatalf("lifecycle not-found must normalize to runtimeapi.ErrNotFound; got %v", got)
+	}
+	if !errors.Is(got, lifecycle.ErrExecutionNotFound) {
+		t.Fatalf("original lifecycle sentinel must be preserved for diagnostics; got %v", got)
+	}
+
+	other := errors.New("agentctl unreachable")
+	if got := normalizeRuntimeStopError(other); got != other {
+		t.Fatalf("unrelated error must pass through unchanged; got %v, want %v", got, other)
+	}
+}
+
 // jiraSecretAdapter Set/Exists branching is tested in
 // internal/integrations/secretadapter/secretadapter_test.go now that the
 // upsert helper lives there.
diff --git a/apps/backend/internal/backendapp/branch_materializer_test.go b/apps/backend/internal/backendapp/branch_materializer_test.go
index 80c521eca3..1543fc0c8e 100644
--- a/apps/backend/internal/backendapp/branch_materializer_test.go
+++ b/apps/backend/internal/backendapp/branch_materializer_test.go
@@ -19,6 +19,16 @@ import (
 	"github.com/kandev/kandev/internal/worktree"
 )
 
+// canonicalTempDir resolves symlinks so macOS /var temp roots pass owned-root guards.
+func canonicalTempDir(t *testing.T) string {
+	t.Helper()
+	d, err := filepath.EvalSymlinks(t.TempDir())
+	if err != nil {
+		t.Fatalf("EvalSymlinks: %v", err)
+	}
+	return d
+}
+
 // stubRescanner records calls so the materializer test can assert that the
 // agentctl rescan was triggered with the expected work_dir (task root) and
 // that the frontend-visible "worktree materialized" event also fired.
@@ -198,7 +208,7 @@ func TestBranchMaterializer_SecondBranchKeepsTaskRootPromoted(t *testing.T) {
 func setupMaterializerScenario(t *testing.T) (repoPath, taskRoot, primaryPath string) {
 	t.Helper()
 
-	tmp := t.TempDir()
+	tmp := canonicalTempDir(t)
 	bareDir := filepath.Join(tmp, "origin.git")
 	runGit(t, tmp, "init", "--bare", "-b", "main", bareDir)
 
diff --git a/apps/backend/internal/backendapp/cron.go b/apps/backend/internal/backendapp/cron.go
index 7eefc7260f..5b65e05add 100644
--- a/apps/backend/internal/backendapp/cron.go
+++ b/apps/backend/internal/backendapp/cron.go
@@ -36,7 +36,15 @@ func startCronScheduler(
 ) *schedulercron.Loop {
 	heartbeat := buildHeartbeatHandler(repos, dispatcher, log)
 	budget := buildBudgetHandler(repos, dispatcher, log)
-	routines := schedulercron.NewRoutinesHandler(routineSvc, nil, log)
+	// Only wire a routines ticker when the office routines service exists.
+	// Assigning a nil *RoutineService straight into the RoutineTicker
+	// interface would produce a non-nil typed-nil interface and panic on
+	// every tick when Office is disabled.
+	var routineTicker schedulercron.RoutineTicker
+	if routineSvc != nil {
+		routineTicker = routineSvc
+	}
+	routines := schedulercron.NewRoutinesHandler(routineTicker, nil, log)
 	loop := schedulercron.NewLoop(schedulercron.DefaultTickInterval, log,
 		heartbeat, budget, routines, officeRecovery)
 	loop.Start(ctx)
diff --git a/apps/backend/internal/backendapp/httpserver_test.go b/apps/backend/internal/backendapp/httpserver_test.go
index 6f4a08be26..dc404f1e30 100644
--- a/apps/backend/internal/backendapp/httpserver_test.go
+++ b/apps/backend/internal/backendapp/httpserver_test.go
@@ -52,6 +52,21 @@ func freePort(t *testing.T) int {
 	return port
 }
 
+// requireLoopbackAlias skips the test when host cannot be bound. Linux treats
+// all of 127.0.0.0/8 as loopback, but macOS only configures 127.0.0.1 by
+// default, so multi-loopback binding tests are unrunnable there without an
+// explicit lo0 alias.
+func requireLoopbackAlias(t *testing.T, host string) {
+	t.Helper()
+	ln, err := net.Listen("tcp", net.JoinHostPort(host, "0"))
+	if err != nil {
+		t.Skipf("loopback alias %s not available on this host: %v", host, err)
+	}
+	if err := ln.Close(); err != nil {
+		t.Fatalf("close loopback probe listener: %v", err)
+	}
+}
+
 func noContentServer() *http.Server {
 	return &http.Server{
 		Handler: http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
@@ -109,6 +124,7 @@ func shutdown(t *testing.T, listeners *serverListeners, server *http.Server) {
 }
 
 func TestStartHTTPServersMultipleLoopbackAddresses(t *testing.T) {
+	requireLoopbackAlias(t, "127.0.0.2")
 	log := testLogger(t)
 	port := freePort(t)
 	server := noContentServer()
@@ -152,6 +168,7 @@ func TestStartHTTPServersAllFailIsFatal(t *testing.T) {
 }
 
 func TestStartHTTPServersPartialFailSelfHeals(t *testing.T) {
+	requireLoopbackAlias(t, "127.0.0.2")
 	defer goleak.VerifyNone(t)
 
 	// Shorten the retry cadence for the test and restore it after.
diff --git a/apps/backend/internal/backendapp/orchestrator.go b/apps/backend/internal/backendapp/orchestrator.go
index 5f3ccd907a..af7941b2ce 100644
--- a/apps/backend/internal/backendapp/orchestrator.go
+++ b/apps/backend/internal/backendapp/orchestrator.go
@@ -104,6 +104,9 @@ func provideOrchestrator(
 		orchestratorSvc.SetTaskGitCredentialPolicyResolver(githubExecutorCredentialPolicyAdapter{service: githubSvc})
 	}
 	taskSvc.SetExecutionStopper(orchestratorSvc)
+	// Runtime-aware liveness lets durable cleanup treat a not-found stop for a
+	// confirmed-dead local runtime as already stopped instead of retrying forever.
+	taskSvc.SetRowLivenessProber(agentManagerClient)
 	taskSvc.SetContextWindowResetter(orchestratorSvc.ResetContextWindow)
 	taskSvc.SetGitArchiveCapture(orchestratorSvc)
 	orchestratorSvc.SetWorktreeManager(lifecycleMgr.WorktreeManager())
diff --git a/apps/backend/internal/backendapp/scheduler_wiring_test.go b/apps/backend/internal/backendapp/scheduler_wiring_test.go
index 0f9a33b29a..0b65960f60 100644
--- a/apps/backend/internal/backendapp/scheduler_wiring_test.go
+++ b/apps/backend/internal/backendapp/scheduler_wiring_test.go
@@ -41,6 +41,53 @@ func TestGlobalSchedulingStartsOutsideOfficeFeatureGate(t *testing.T) {
 	}
 }
 
+// TestRoutinesHandlerNotWiredWithTypedNilService guards the Office-disabled
+// cron panic regression. startCronScheduler must gate the routines service
+// behind a nil check before assigning it into the RoutineTicker interface;
+// passing the raw *RoutineService parameter (routineSvc) straight into
+// NewRoutinesHandler produces a typed-nil interface that panics every tick
+// when Office is disabled.
+func TestRoutinesHandlerNotWiredWithTypedNilService(t *testing.T) {
+	fset := token.NewFileSet()
+	file, err := parser.ParseFile(fset, "cron.go", nil, 0)
+	if err != nil {
+		t.Fatalf("parse cron.go: %v", err)
+	}
+
+	var startFn *ast.FuncDecl
+	for _, decl := range file.Decls {
+		fn, ok := decl.(*ast.FuncDecl)
+		if ok && fn.Name.Name == "startCronScheduler" {
+			startFn = fn
+			break
+		}
+	}
+	if startFn == nil {
+		t.Fatal("startCronScheduler not found in cron.go")
+	}
+
+	var passesRawService bool
+	ast.Inspect(startFn, func(n ast.Node) bool {
+		call, ok := n.(*ast.CallExpr)
+		if !ok {
+			return true
+		}
+		sel, ok := call.Fun.(*ast.SelectorExpr)
+		if !ok || sel.Sel.Name != "NewRoutinesHandler" || len(call.Args) == 0 {
+			return true
+		}
+		if ident, ok := call.Args[0].(*ast.Ident); ok && ident.Name == "routineSvc" {
+			passesRawService = true
+		}
+		return true
+	})
+
+	if passesRawService {
+		t.Error("startCronScheduler passes the raw routineSvc pointer into NewRoutinesHandler; " +
+			"gate it behind a nil check via a RoutineTicker interface variable to avoid the typed-nil panic")
+	}
+}
+
 func countNamedCalls(fn *ast.FuncDecl, name string) int {
 	count := 0
 	ast.Inspect(fn, func(n ast.Node) bool {
diff --git a/apps/backend/internal/backendapp/workspace_source_materializer_test.go b/apps/backend/internal/backendapp/workspace_source_materializer_test.go
index 670888310c..c7125cf75b 100644
--- a/apps/backend/internal/backendapp/workspace_source_materializer_test.go
+++ b/apps/backend/internal/backendapp/workspace_source_materializer_test.go
@@ -269,7 +269,7 @@ func TestWorkspaceSourceMaterializer_RemoteRejectsLocalOnlyAdditionalRepositoryB
 func TestWorkspaceSourceMaterializer_LocalFolderCreatesLiveTaskEntryAndRebindsSessions(t *testing.T) {
 	ctx := context.Background()
 	repo := newMaterializerRepo(t)
-	tasksBase := filepath.Join(t.TempDir(), "tasks")
+	tasksBase := filepath.Join(canonicalTempDir(t), "tasks")
 	mgr := newMaterializerWorktreeMgr(t, filepath.Join(tasksBase, "task-1"))
 	source := filepath.Join(t.TempDir(), "notes")
 	if err := os.MkdirAll(source, 0o755); err != nil {
@@ -319,7 +319,7 @@ func TestWorkspaceSourceMaterializer_LocalFolderCreatesLiveTaskEntryAndRebindsSe
 func TestWorkspaceSourceMaterializer_LocalFolderUsesPersistedBatchSourceOnlyOnce(t *testing.T) {
 	ctx := context.Background()
 	repo := newMaterializerRepo(t)
-	tasksBase := filepath.Join(t.TempDir(), "tasks")
+	tasksBase := filepath.Join(canonicalTempDir(t), "tasks")
 	mgr := newMaterializerWorktreeMgr(t, filepath.Join(tasksBase, "task-1"))
 	source := filepath.Join(t.TempDir(), "notes")
 	if err := os.MkdirAll(source, 0o755); err != nil {
@@ -356,7 +356,7 @@ func TestWorkspaceSourceMaterializer_LocalFolderUsesPersistedBatchSourceOnlyOnce
 func TestWorkspaceSourceMaterializer_LocalPromotionPreservesPrimaryRepository(t *testing.T) {
 	ctx := context.Background()
 	repo := newMaterializerRepo(t)
-	tasksBase := filepath.Join(t.TempDir(), "tasks")
+	tasksBase := filepath.Join(canonicalTempDir(t), "tasks")
 	mgr := newMaterializerWorktreeMgr(t, filepath.Join(tasksBase, "task-1"))
 	primary := filepath.Join(t.TempDir(), "primary")
 	folder := filepath.Join(t.TempDir(), "notes")
@@ -402,10 +402,10 @@ func TestWorkspaceSourceMaterializer_LocalPromotionPreservesPrimaryRepository(t
 func TestWorkspaceSourceMaterializer_LocalClonesProviderRepositoryBeforeLinking(t *testing.T) {
 	ctx := context.Background()
 	repo := newMaterializerRepo(t)
-	tasksBase := filepath.Join(t.TempDir(), "tasks")
+	tasksBase := filepath.Join(canonicalTempDir(t), "tasks")
 	mgr := newMaterializerWorktreeMgr(t, filepath.Join(tasksBase, "task-1"))
 	seedWorkspaceSourceTask(t, repo, t.TempDir())
-	clonePath := filepath.Join(t.TempDir(), "cloned")
+	clonePath := filepath.Join(canonicalTempDir(t), "cloned")
 	if err := os.MkdirAll(clonePath, 0o755); err != nil {
 		t.Fatal(err)
 	}
@@ -481,9 +481,9 @@ func TestWorkspaceSourceMaterializer_RollsBackLinkAndPathWhenAdoptionFails(t *te
 func TestWorkspaceSourceMaterializer_RebindFailureRestoresEarlierSessionsInReverseOrder(t *testing.T) {
 	ctx := context.Background()
 	repo := newMaterializerRepo(t)
-	tasksBase := filepath.Join(t.TempDir(), "tasks")
+	tasksBase := filepath.Join(canonicalTempDir(t), "tasks")
 	mgr := newMaterializerWorktreeMgr(t, filepath.Join(tasksBase, "task-1"))
-	source := filepath.Join(t.TempDir(), "notes")
+	source := filepath.Join(canonicalTempDir(t), "notes")
 	if err := os.MkdirAll(source, 0o755); err != nil {
 		t.Fatal(err)
 	}
diff --git a/apps/backend/internal/launcher/service_test.go b/apps/backend/internal/launcher/service_test.go
index 2cbfc45c06..cbc8cf2d44 100644
--- a/apps/backend/internal/launcher/service_test.go
+++ b/apps/backend/internal/launcher/service_test.go
@@ -460,7 +460,7 @@ func TestServiceNodeToolBinDirsResolvesFnmMultishellSymlinks(t *testing.T) {
 	if runtime.GOOS == "windows" {
 		t.Skip("service PATH rendering is POSIX-only")
 	}
-	tmp := t.TempDir()
+	tmp := canonicalTempDir(t)
 	stableBin := filepath.Join(tmp, "home", "alice", ".local", "share", "fnm", "node-versions", "v25.2.1", "installation", "bin")
 	multishellBin := filepath.Join(tmp, "run", "user", "1000", "fnm_multishells", "12345_67890", "bin")
 	for _, dir := range []string{stableBin, multishellBin} {
@@ -522,3 +522,14 @@ func TestBackupUnmanagedServiceFileSkipsManagedFile(t *testing.T) {
 		t.Fatalf("managed file should not create backup, stat err=%v", err)
 	}
 }
+
+// canonicalTempDir returns t.TempDir() with symlinks resolved so tests agree
+// with production code that reports canonical paths (macOS /var -> /private/var).
+func canonicalTempDir(t *testing.T) string {
+	t.Helper()
+	resolved, err := filepath.EvalSymlinks(t.TempDir())
+	if err != nil {
+		t.Fatal(err)
+	}
+	return resolved
+}
diff --git a/apps/backend/internal/launcher/start_test.go b/apps/backend/internal/launcher/start_test.go
index 024cb284d3..a9f81e2104 100644
--- a/apps/backend/internal/launcher/start_test.go
+++ b/apps/backend/internal/launcher/start_test.go
@@ -63,7 +63,7 @@ func TestRunStartUsesSelfExecutableAndBackendCWD(t *testing.T) {
 		launchManaged = oldLaunchManaged
 	})
 
-	exe := filepath.Join(t.TempDir(), "bin", "kandev")
+	exe := filepath.Join(canonicalTempDir(t), "bin", "kandev")
 	executablePath = func() (string, error) {
 		return exe, nil
 	}
@@ -73,7 +73,9 @@ func TestRunStartUsesSelfExecutableAndBackendCWD(t *testing.T) {
 		got = cfg
 		return 42
 	}
-	t.Setenv("KANDEV_HOME_DIR", t.TempDir())
+	// ensureDataDir rejects a data dir with any symlinked ancestor, so the home
+	// dir must be canonical (macOS temp dirs sit under the /var -> /private/var link).
+	t.Setenv("KANDEV_HOME_DIR", canonicalTempDir(t))
 
 	code := runStart(context.Background(), Options{Command: CommandStart, BackendPort: 48123, Headless: true})
 	if code != 42 {
diff --git a/apps/backend/internal/notifications/service/service_test.go b/apps/backend/internal/notifications/service/service_test.go
index 81dcfef68b..ae52e3af0e 100644
--- a/apps/backend/internal/notifications/service/service_test.go
+++ b/apps/backend/internal/notifications/service/service_test.go
@@ -146,6 +146,10 @@ func TestNewServiceRetainsSystemProviderForNonDesktopLaunch(t *testing.T) {
 }
 
 func TestSemanticOccurrencesUseEventSpecificCopyAndOccurrenceIdempotency(t *testing.T) {
+	// Keep the auto-provisioned system provider out so the test only exercises
+	// the single configured local provider; SystemProvider.Available() is true
+	// on desktop platforms (e.g. macOS) and would add an extra delivery.
+	t.Setenv(desktopNativeNotificationsEnv, "true")
 	log, err := logger.NewFromZap(zap.NewNop())
 	if err != nil {
 		t.Fatalf("create logger: %v", err)
@@ -302,6 +306,10 @@ func TestUpdateAvailabilityRoutesProviderScopedOccurrenceWithReleasePayload(t *t
 }
 
 func TestNoEligibleLocalUpdateSubscriberReleasesOccurrenceClaimForReplay(t *testing.T) {
+	// Keep the auto-provisioned system provider out so the test only exercises
+	// the single configured local provider; SystemProvider.Available() is true
+	// on desktop platforms (e.g. macOS) and would add an extra delivery.
+	t.Setenv(desktopNativeNotificationsEnv, "true")
 	log, err := logger.NewFromZap(zap.NewNop())
 	if err != nil {
 		t.Fatalf("create logger: %v", err)
diff --git a/apps/backend/internal/orchestrator/event_handlers_github.go b/apps/backend/internal/orchestrator/event_handlers_github.go
index 9e49842a90..d5f4c86679 100644
--- a/apps/backend/internal/orchestrator/event_handlers_github.go
+++ b/apps/backend/internal/orchestrator/event_handlers_github.go
@@ -448,7 +448,7 @@ func buildReviewTaskRequest(evt *github.NewReviewPREvent, repositories []ReviewT
 		WorkspaceID:    evt.WorkspaceID,
 		WorkflowID:     evt.WorkflowID,
 		WorkflowStepID: evt.WorkflowStepID,
-		Title:          fmt.Sprintf("PR #%d: %s", pr.Number, pr.Title),
+		Title:          service.TruncateTaskTitle(fmt.Sprintf("PR #%d: %s", pr.Number, pr.Title)),
 		Description:    interpolateReviewPrompt(evt.Prompt, pr),
 		Repositories:   repositories,
 		Metadata: map[string]interface{}{
@@ -474,6 +474,13 @@ func buildReviewTaskRequest(evt *github.NewReviewPREvent, repositories []ReviewT
 	}
 }
 
+// buildIssueTaskTitle builds the "Issue #<n>: <title>" task title for an issue
+// watcher, shortened to the task title limit so an over-long remote issue title
+// does not cause CreateIssueTask to reject the whole task.
+func buildIssueTaskTitle(number int, title string) string {
+	return service.TruncateTaskTitle(fmt.Sprintf("Issue #%d: %s", number, title))
+}
+
 // shouldAutoStartStep checks if the workflow step has the OnEnterAutoStartAgent action.
 func (s *Service) shouldAutoStartStep(ctx context.Context, stepID string) bool {
 	if s.workflowStepGetter == nil || stepID == "" {
@@ -1365,7 +1372,7 @@ func (s *Service) createIssueTask(ctx context.Context, evt *github.NewIssueEvent
 		WorkspaceID:    evt.WorkspaceID,
 		WorkflowID:     evt.WorkflowID,
 		WorkflowStepID: evt.WorkflowStepID,
-		Title:          fmt.Sprintf("Issue #%d: %s", issue.Number, issue.Title),
+		Title:          buildIssueTaskTitle(issue.Number, issue.Title),
 		Description:    interpolateIssuePrompt(evt.Prompt, issue),
 		Metadata: map[string]interface{}{
 			issueWatchIDKey:       evt.IssueWatchID,
diff --git a/apps/backend/internal/orchestrator/event_handlers_github_review_test.go b/apps/backend/internal/orchestrator/event_handlers_github_review_test.go
index 71c596bbdf..6595b5f65e 100644
--- a/apps/backend/internal/orchestrator/event_handlers_github_review_test.go
+++ b/apps/backend/internal/orchestrator/event_handlers_github_review_test.go
@@ -2,18 +2,141 @@ package orchestrator
 
 import (
 	"context"
+	"strings"
 	"sync/atomic"
 	"testing"
 	"time"
+	"unicode/utf8"
 
 	"github.com/kandev/kandev/internal/github"
 	"github.com/kandev/kandev/internal/orchestrator/executor"
 	"github.com/kandev/kandev/internal/orchestrator/watcher"
 	taskmodels "github.com/kandev/kandev/internal/task/models"
+	taskservice "github.com/kandev/kandev/internal/task/service"
 	wfmodels "github.com/kandev/kandev/internal/workflow/models"
 	v1 "github.com/kandev/kandev/pkg/api/v1"
 )
 
+// TestBuildReviewTaskRequest_TruncatesTitle is the regression test for the
+// dropped-review-task bug: a PR whose "PR #<n>: <title>" string exceeds the
+// 60-rune task title limit must be shortened (prefix kept, ≤60 runes, trailing
+// ellipsis) so CreateReviewTask accepts it instead of rejecting the whole task.
+func TestBuildReviewTaskRequest_TruncatesTitle(t *testing.T) {
+	tests := []struct {
+		name      string
+		prTitle   string
+		wantExact string // when non-empty, the full expected title
+		wantTrunc bool
+	}{
+		{
+			name:      "short ascii unchanged",
+			prTitle:   "Fix login bug",
+			wantExact: "PR #42: Fix login bug",
+		},
+		{
+			name:      "long ascii truncated",
+			prTitle:   strings.Repeat("a", 100),
+			wantTrunc: true,
+		},
+		{
+			name:      "long multibyte not split",
+			prTitle:   strings.Repeat("é", 100),
+			wantTrunc: true,
+		},
+		{
+			// Prefix "PR #42: " is 8 runes, so a 52-rune PR title yields exactly
+			// the 60-rune limit and must pass through untouched (boundary case).
+			name:      "exactly at limit unchanged",
+			prTitle:   strings.Repeat("a", taskservice.TaskTitleMaxLength-len("PR #42: ")),
+			wantExact: "PR #42: " + strings.Repeat("a", taskservice.TaskTitleMaxLength-len("PR #42: ")),
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			evt := newReviewEvent()
+			evt.PR.Title = tt.prTitle
+			req := buildReviewTaskRequest(evt, nil, "acme/widget")
+
+			if got := utf8.RuneCountInString(req.Title); got > taskservice.TaskTitleMaxLength {
+				t.Fatalf("title = %d runes, want ≤ %d", got, taskservice.TaskTitleMaxLength)
+			}
+			if !utf8.ValidString(req.Title) {
+				t.Fatalf("title %q is not valid UTF-8; byte-based truncation split a rune", req.Title)
+			}
+			if err := taskservice.ValidateTaskTitle(req.Title); err != nil {
+				t.Fatalf("ValidateTaskTitle: %v", err)
+			}
+			if !strings.HasPrefix(req.Title, "PR #42:") {
+				t.Errorf("title %q lost the PR prefix", req.Title)
+			}
+			if tt.wantExact != "" && req.Title != tt.wantExact {
+				t.Errorf("title = %q, want %q", req.Title, tt.wantExact)
+			}
+			if tt.wantTrunc && !strings.HasSuffix(req.Title, "…") {
+				t.Errorf("truncated title %q should end with ellipsis", req.Title)
+			}
+		})
+	}
+}
+
+// TestBuildIssueTaskTitle_TruncatesTitle mirrors the review-title regression for
+// the GitHub issue watcher's "Issue #<n>: <title>" builder.
+func TestBuildIssueTaskTitle_TruncatesTitle(t *testing.T) {
+	tests := []struct {
+		name       string
+		issueTitle string
+		wantExact  string
+		wantTrunc  bool
+	}{
+		{
+			name:       "short ascii unchanged",
+			issueTitle: "Broken export",
+			wantExact:  "Issue #7: Broken export",
+		},
+		{
+			name:       "long ascii truncated",
+			issueTitle: strings.Repeat("b", 100),
+			wantTrunc:  true,
+		},
+		{
+			name:       "long multibyte not split",
+			issueTitle: strings.Repeat("ü", 100),
+			wantTrunc:  true,
+		},
+		{
+			// Prefix "Issue #7: " is 10 runes, so a 50-rune issue title yields
+			// exactly the 60-rune limit and must pass through untouched.
+			name:       "exactly at limit unchanged",
+			issueTitle: strings.Repeat("b", taskservice.TaskTitleMaxLength-len("Issue #7: ")),
+			wantExact:  "Issue #7: " + strings.Repeat("b", taskservice.TaskTitleMaxLength-len("Issue #7: ")),
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := buildIssueTaskTitle(7, tt.issueTitle)
+
+			if n := utf8.RuneCountInString(got); n > taskservice.TaskTitleMaxLength {
+				t.Fatalf("title = %d runes, want ≤ %d", n, taskservice.TaskTitleMaxLength)
+			}
+			if !utf8.ValidString(got) {
+				t.Fatalf("title %q is not valid UTF-8; byte-based truncation split a rune", got)
+			}
+			if err := taskservice.ValidateTaskTitle(got); err != nil {
+				t.Fatalf("ValidateTaskTitle: %v", err)
+			}
+			if !strings.HasPrefix(got, "Issue #7:") {
+				t.Errorf("title %q lost the Issue prefix", got)
+			}
+			if tt.wantExact != "" && got != tt.wantExact {
+				t.Errorf("title = %q, want %q", got, tt.wantExact)
+			}
+			if tt.wantTrunc && !strings.HasSuffix(got, "…") {
+				t.Errorf("truncated title %q should end with ellipsis", got)
+			}
+		})
+	}
+}
+
 // countingReviewTaskCreator records how many times CreateReviewTask was called.
 type countingReviewTaskCreator struct {
 	calls    int
diff --git a/apps/backend/internal/orchestrator/executor/executor_interaction.go b/apps/backend/internal/orchestrator/executor/executor_interaction.go
index 1cc97edc07..647e093161 100644
--- a/apps/backend/internal/orchestrator/executor/executor_interaction.go
+++ b/apps/backend/internal/orchestrator/executor/executor_interaction.go
@@ -21,6 +21,14 @@ import (
 func (e *Executor) Stop(ctx context.Context, sessionID string, reason string, force bool) error {
 	session, err := e.repo.GetTaskSession(ctx, sessionID)
 	if err != nil {
+		// A genuinely missing session row means the runtime this stop would
+		// target is gone; normalize to the public not-found sentinel so durable
+		// cleanup can treat a confirmed-dead local runtime as already stopped.
+		// An unrelated store error is NOT reclassified — it stays a plain
+		// ErrExecutionNotFound so a transient failure remains retryable.
+		if errors.Is(err, models.ErrTaskSessionNotFound) {
+			return fmt.Errorf("%w: %w: %w", ErrExecutionNotFound, runtimeapi.ErrNotFound, err)
+		}
 		return ErrExecutionNotFound
 	}
 	return e.stopWithSession(ctx, session, reason, force)
diff --git a/apps/backend/internal/orchestrator/executor/executor_interaction_test.go b/apps/backend/internal/orchestrator/executor/executor_interaction_test.go
index e574daa4d6..a234935d22 100644
--- a/apps/backend/internal/orchestrator/executor/executor_interaction_test.go
+++ b/apps/backend/internal/orchestrator/executor/executor_interaction_test.go
@@ -108,6 +108,46 @@ func TestStopSessionDetailed_ClassifiesExecutionLookup(t *testing.T) {
 	}
 }
 
+// TestStop_MissingSessionReportsRuntimeNotFound covers the boundary contract the
+// durable task cleanup depends on: when the task_session row is genuinely gone,
+// Stop must report the runtime as not-found (wrapping the public
+// runtimeapi.ErrNotFound sentinel) so cleanup can classify a confirmed-dead
+// local runtime as already-stopped. An unrelated store error must NOT be
+// collapsed into a not-found result.
+func TestStop_MissingSessionReportsRuntimeNotFound(t *testing.T) {
+	t.Run("missing session row normalizes to runtime not-found", func(t *testing.T) {
+		repo := newMockRepository()
+		repo.getTaskSessionFunc = func(context.Context, string) (*models.TaskSession, error) {
+			return nil, fmt.Errorf("agent session not found: %w", models.ErrTaskSessionNotFound)
+		}
+		exec := newTestExecutor(t, &mockAgentManager{}, repo)
+
+		err := exec.Stop(context.Background(), "sess-gone", "cleanup", true)
+		if !errors.Is(err, ErrExecutionNotFound) {
+			t.Fatalf("error = %v, want ErrExecutionNotFound", err)
+		}
+		if !errors.Is(err, runtimeapi.ErrNotFound) {
+			t.Fatalf("missing session must normalize to runtimeapi.ErrNotFound; got %v", err)
+		}
+	})
+
+	t.Run("unrelated store error is not collapsed to not-found", func(t *testing.T) {
+		repo := newMockRepository()
+		repo.getTaskSessionFunc = func(context.Context, string) (*models.TaskSession, error) {
+			return nil, errors.New("database is unavailable")
+		}
+		exec := newTestExecutor(t, &mockAgentManager{}, repo)
+
+		err := exec.Stop(context.Background(), "sess-x", "cleanup", true)
+		if !errors.Is(err, ErrExecutionNotFound) {
+			t.Fatalf("error = %v, want ErrExecutionNotFound", err)
+		}
+		if errors.Is(err, runtimeapi.ErrNotFound) {
+			t.Fatalf("an unrelated store error must not be reclassified as runtime not-found; got %v", err)
+		}
+	})
+}
+
 func TestStopSessionDetailed_RejectsInvalidSession(t *testing.T) {
 	exec := newTestExecutor(t, &mockAgentManager{}, newMockRepository())
 
diff --git a/apps/backend/internal/orchestrator/reconcile_restart_test.go b/apps/backend/internal/orchestrator/reconcile_restart_test.go
index 2bfe7911c1..cc9f9bf52f 100644
--- a/apps/backend/internal/orchestrator/reconcile_restart_test.go
+++ b/apps/backend/internal/orchestrator/reconcile_restart_test.go
@@ -2,13 +2,20 @@ package orchestrator
 
 import (
 	"context"
+	"errors"
+	"fmt"
 	"testing"
 	"time"
 
+	runtimeapi "github.com/kandev/kandev/internal/agent/runtime"
 	"github.com/kandev/kandev/internal/agentruntime"
 	"github.com/kandev/kandev/internal/task/models"
 )
 
+// errWorkTransient is a non-not-found stop error used to assert that a transient
+// stop failure never causes a confirmed-dead row to be pruned.
+var errWorkTransient = errors.New("runtime stop transient failure")
+
 // TestReconcileSessionsOnStartupMakesRowsTrue is the restart-reconciliation
 // integration test for #1597 startup reconciliation (the backlog stops
 // growing, rows are made true, resumability is never lost). After a restart,
@@ -185,6 +192,145 @@ func TestReconcileSessionsOnStartup_MissingSessionStopsAgentAndDeletesRow(t *tes
 	}
 }
 
+// TestReconcileSessionsOnStartup_MissingSessionDeadRowPrunedOnNotFound is the
+// regression test for the stale-orphan-row bug: a missing-session row whose
+// runtime handle is already gone returns a not-found error from the stop, which
+// the old code treated as "stop failed" and preserved forever. A confirmed-dead
+// LOCAL row must instead treat the not-found stop as already-stopped and prune
+// the row under the resume-safety invariant (no resume_token → delete).
+func TestReconcileSessionsOnStartup_MissingSessionDeadRowPrunedOnNotFound(t *testing.T) {
+	repo := setupTestRepo(t)
+	ctx := context.Background()
+	now := time.Now().UTC()
+
+	if err := repo.UpsertExecutorRunning(ctx, &models.ExecutorRunning{
+		ID: "sDead", SessionID: "sDead", TaskID: "taskDead", Runtime: agentruntime.RuntimeStandalone,
+		Status: models.ExecutorRunningStatusRunning, AgentExecutionID: "execDead", LocalPID: 4242,
+		CreatedAt: now, UpdatedAt: now,
+	}); err != nil {
+		t.Fatalf("upsert sDead: %v", err)
+	}
+
+	agentMgr := &mockAgentManager{
+		// The runtime seam (lifecycleAdapter) normalizes the lifecycle not-found
+		// sentinel to runtimeapi.ErrNotFound before it reaches the orchestrator.
+		stopAgentWithReasonErr: fmt.Errorf("stop agent: %w", runtimeapi.ErrNotFound),
+		rowLivenessFn: func(*models.ExecutorRunning) models.ProcessLiveness {
+			return models.ProcessLivenessDead
+		},
+	}
+	svc := createTestServiceWithAgent(repo, newMockStepGetter(), newMockTaskRepo(), agentMgr)
+	svc.reconcileSessionsOnStartup(ctx)
+
+	if _, err := repo.GetExecutorRunningBySessionID(ctx, "sDead"); err == nil {
+		t.Error("confirmed-dead local orphan row with a not-found stop must be pruned, not preserved")
+	}
+}
+
+// TestReconcileSessionsOnStartup_MissingSessionDeadRowWithTokenRepaired covers
+// the resume-safety half of the confirmed-dead not-found path: a dead local row
+// that still carries a resume_token is repaired in place (never deleted).
+func TestReconcileSessionsOnStartup_MissingSessionDeadRowWithTokenRepaired(t *testing.T) {
+	repo := setupTestRepo(t)
+	ctx := context.Background()
+	now := time.Now().UTC()
+
+	if err := repo.UpsertExecutorRunning(ctx, &models.ExecutorRunning{
+		ID: "sTok", SessionID: "sTok", TaskID: "taskTok", Runtime: agentruntime.RuntimeStandalone,
+		Status: models.ExecutorRunningStatusRunning, AgentExecutionID: "execTok",
+		ResumeToken: "tokTok", Resumable: true, LocalPID: 5252,
+		CreatedAt: now, UpdatedAt: now,
+	}); err != nil {
+		t.Fatalf("upsert sTok: %v", err)
+	}
+
+	agentMgr := &mockAgentManager{
+		stopAgentWithReasonErr: fmt.Errorf("stop agent: %w", runtimeapi.ErrNotFound),
+		rowLivenessFn: func(*models.ExecutorRunning) models.ProcessLiveness {
+			return models.ProcessLivenessDead
+		},
+	}
+	svc := createTestServiceWithAgent(repo, newMockStepGetter(), newMockTaskRepo(), agentMgr)
+	svc.reconcileSessionsOnStartup(ctx)
+
+	row, err := repo.GetExecutorRunningBySessionID(ctx, "sTok")
+	if err != nil {
+		t.Fatalf("confirmed-dead row holding a resume_token must be preserved: %v", err)
+	}
+	if row.ResumeToken != "tokTok" {
+		t.Errorf("resume_token must survive repair; got %q", row.ResumeToken)
+	}
+	if row.Status != models.ExecutorRunningStatusStopped || row.LocalPID != 0 {
+		t.Errorf("dead row must be repaired to stopped with cleared local_pid; got status=%q local_pid=%d", row.Status, row.LocalPID)
+	}
+}
+
+// TestReconcileSessionsOnStartup_MissingSessionUnknownRowPreservedOnNotFound
+// guards the anti-blanket-ignore rule: a not-found stop for a row whose local
+// liveness is Unknown (remote/containerized/no local handle) must NOT prune the
+// row — only a confirmed-dead LOCAL row is reclassified.
+func TestReconcileSessionsOnStartup_MissingSessionUnknownRowPreservedOnNotFound(t *testing.T) {
+	repo := setupTestRepo(t)
+	ctx := context.Background()
+	now := time.Now().UTC()
+
+	if err := repo.UpsertExecutorRunning(ctx, &models.ExecutorRunning{
+		ID: "sRemote", SessionID: "sRemote", TaskID: "taskRemote", Runtime: agentruntime.RuntimeSSH,
+		Status: models.ExecutorRunningStatusRunning, AgentExecutionID: "execRemote",
+		ResumeToken: "tokRemote", PID: 4444, CreatedAt: now, UpdatedAt: now,
+	}); err != nil {
+		t.Fatalf("upsert sRemote: %v", err)
+	}
+
+	agentMgr := &mockAgentManager{
+		stopAgentWithReasonErr: fmt.Errorf("stop agent: %w", runtimeapi.ErrNotFound),
+		rowLivenessFn: func(*models.ExecutorRunning) models.ProcessLiveness {
+			return models.ProcessLivenessUnknown
+		},
+	}
+	svc := createTestServiceWithAgent(repo, newMockStepGetter(), newMockTaskRepo(), agentMgr)
+	svc.reconcileSessionsOnStartup(ctx)
+
+	row, err := repo.GetExecutorRunningBySessionID(ctx, "sRemote")
+	if err != nil {
+		t.Fatalf("unknown/remote row must be preserved on a host-local not-found: %v", err)
+	}
+	if row.ResumeToken != "tokRemote" || row.PID != 4444 {
+		t.Errorf("unknown/remote row must be left intact; got token=%q pid=%d", row.ResumeToken, row.PID)
+	}
+}
+
+// TestReconcileSessionsOnStartup_MissingSessionNonNotFoundPreserved guards the
+// retryable-failure rule: a stop that fails with a non-not-found error must
+// preserve the row even when the row is confirmed dead — a transient stop
+// failure is never mistaken for an absent runtime.
+func TestReconcileSessionsOnStartup_MissingSessionNonNotFoundPreserved(t *testing.T) {
+	repo := setupTestRepo(t)
+	ctx := context.Background()
+	now := time.Now().UTC()
+
+	if err := repo.UpsertExecutorRunning(ctx, &models.ExecutorRunning{
+		ID: "sErr", SessionID: "sErr", TaskID: "taskErr", Runtime: agentruntime.RuntimeStandalone,
+		Status: models.ExecutorRunningStatusRunning, AgentExecutionID: "execErr", LocalPID: 6262,
+		CreatedAt: now, UpdatedAt: now,
+	}); err != nil {
+		t.Fatalf("upsert sErr: %v", err)
+	}
+
+	agentMgr := &mockAgentManager{
+		stopAgentWithReasonErr: errWorkTransient, // not a not-found sentinel
+		rowLivenessFn: func(*models.ExecutorRunning) models.ProcessLiveness {
+			return models.ProcessLivenessDead
+		},
+	}
+	svc := createTestServiceWithAgent(repo, newMockStepGetter(), newMockTaskRepo(), agentMgr)
+	svc.reconcileSessionsOnStartup(ctx)
+
+	if _, err := repo.GetExecutorRunningBySessionID(ctx, "sErr"); err != nil {
+		t.Errorf("a non-not-found stop failure must preserve the row for retry: %v", err)
+	}
+}
+
 // TestReconcileSessionsOnStartup_CreatedSessionRowPrunedUnlessResumable covers
 // the never-started-session cleanup site, which routes through the resume-safety
 // invariant rather than deleting unconditionally: a Created session's row with
@@ -227,3 +373,179 @@ func TestReconcileSessionsOnStartup_CreatedSessionRowPrunedUnlessResumable(t *te
 		t.Errorf("sF should be repaired to stopped with cleared local_pid; got status=%q local_pid=%d", f.Status, f.LocalPID)
 	}
 }
+
+// TestReconcileSessionsOnStartup_TerminalDeadRowPrunedOnNotFound is the
+// regression test for the "failed to stop terminal session runtime; preserving
+// executor record" warning: a COMPLETED/CANCELLED session whose confirmed-dead
+// LOCAL runtime returns a not-found stop must be treated as already-stopped and
+// its tokenless row pruned — not preserved forever. Mirrors the missing-session
+// classification so terminal reconciliation stops leaking stale rows.
+func TestReconcileSessionsOnStartup_TerminalDeadRowPrunedOnNotFound(t *testing.T) {
+	for _, state := range []models.TaskSessionState{
+		models.TaskSessionStateCompleted,
+		models.TaskSessionStateCancelled,
+	} {
+		t.Run(string(state), func(t *testing.T) {
+			repo := setupTestRepo(t)
+			ctx := context.Background()
+			now := time.Now().UTC()
+
+			seedTaskAndSession(t, repo, "taskT", "sT", state)
+			if err := repo.UpsertExecutorRunning(ctx, &models.ExecutorRunning{
+				ID: "sT", SessionID: "sT", TaskID: "taskT", Runtime: agentruntime.RuntimeStandalone,
+				Status: models.ExecutorRunningStatusRunning, AgentExecutionID: "execT", LocalPID: 7272,
+				CreatedAt: now, UpdatedAt: now,
+			}); err != nil {
+				t.Fatalf("upsert sT: %v", err)
+			}
+
+			agentMgr := &mockAgentManager{
+				stopAgentWithReasonErr: fmt.Errorf("stop agent: %w", runtimeapi.ErrNotFound),
+				rowLivenessFn: func(*models.ExecutorRunning) models.ProcessLiveness {
+					return models.ProcessLivenessDead
+				},
+			}
+			svc := createTestServiceWithAgent(repo, newMockStepGetter(), newMockTaskRepo(), agentMgr)
+			svc.reconcileSessionsOnStartup(ctx)
+
+			if _, err := repo.GetExecutorRunningBySessionID(ctx, "sT"); err == nil {
+				t.Error("confirmed-dead terminal row with a not-found stop must be pruned, not preserved")
+			}
+		})
+	}
+}
+
+// TestReconcileSessionsOnStartup_TerminalDeadRowWithTokenRepaired covers the
+// resume-safety half of the terminal not-found path: a terminal row still
+// carrying a resume_token is repaired in place, never deleted.
+func TestReconcileSessionsOnStartup_TerminalDeadRowWithTokenRepaired(t *testing.T) {
+	repo := setupTestRepo(t)
+	ctx := context.Background()
+	now := time.Now().UTC()
+
+	seedTaskAndSession(t, repo, "taskTT", "sTT", models.TaskSessionStateCompleted)
+	if err := repo.UpsertExecutorRunning(ctx, &models.ExecutorRunning{
+		ID: "sTT", SessionID: "sTT", TaskID: "taskTT", Runtime: agentruntime.RuntimeStandalone,
+		Status: models.ExecutorRunningStatusRunning, AgentExecutionID: "execTT",
+		ResumeToken: "tokTT", Resumable: true, LocalPID: 8282,
+		CreatedAt: now, UpdatedAt: now,
+	}); err != nil {
+		t.Fatalf("upsert sTT: %v", err)
+	}
+
+	agentMgr := &mockAgentManager{
+		stopAgentWithReasonErr: fmt.Errorf("stop agent: %w", runtimeapi.ErrNotFound),
+		rowLivenessFn: func(*models.ExecutorRunning) models.ProcessLiveness {
+			return models.ProcessLivenessDead
+		},
+	}
+	svc := createTestServiceWithAgent(repo, newMockStepGetter(), newMockTaskRepo(), agentMgr)
+	svc.reconcileSessionsOnStartup(ctx)
+
+	row, err := repo.GetExecutorRunningBySessionID(ctx, "sTT")
+	if err != nil {
+		t.Fatalf("terminal row holding a resume_token must be preserved: %v", err)
+	}
+	if row.ResumeToken != "tokTT" {
+		t.Errorf("resume_token must survive repair; got %q", row.ResumeToken)
+	}
+	if row.Status != models.ExecutorRunningStatusStopped || row.LocalPID != 0 {
+		t.Errorf("dead terminal row must be repaired to stopped with cleared local_pid; got status=%q local_pid=%d", row.Status, row.LocalPID)
+	}
+}
+
+// TestReconcileSessionsOnStartup_TerminalUnknownRowPreservedOnNotFound guards the
+// anti-blanket-ignore rule for the terminal path: a not-found stop for a row
+// whose local liveness is Unknown (remote/no local handle) must NOT prune the
+// row — only a confirmed-dead LOCAL row is reclassified.
+func TestReconcileSessionsOnStartup_TerminalUnknownRowPreservedOnNotFound(t *testing.T) {
+	repo := setupTestRepo(t)
+	ctx := context.Background()
+	now := time.Now().UTC()
+
+	seedTaskAndSession(t, repo, "taskTU", "sTU", models.TaskSessionStateCancelled)
+	if err := repo.UpsertExecutorRunning(ctx, &models.ExecutorRunning{
+		ID: "sTU", SessionID: "sTU", TaskID: "taskTU", Runtime: agentruntime.RuntimeSSH,
+		Status: models.ExecutorRunningStatusRunning, AgentExecutionID: "execTU",
+		PID: 9191, CreatedAt: now, UpdatedAt: now,
+	}); err != nil {
+		t.Fatalf("upsert sTU: %v", err)
+	}
+
+	agentMgr := &mockAgentManager{
+		stopAgentWithReasonErr: fmt.Errorf("stop agent: %w", runtimeapi.ErrNotFound),
+		rowLivenessFn: func(*models.ExecutorRunning) models.ProcessLiveness {
+			return models.ProcessLivenessUnknown
+		},
+	}
+	svc := createTestServiceWithAgent(repo, newMockStepGetter(), newMockTaskRepo(), agentMgr)
+	svc.reconcileSessionsOnStartup(ctx)
+
+	if _, err := repo.GetExecutorRunningBySessionID(ctx, "sTU"); err != nil {
+		t.Fatalf("unknown/remote terminal row must be preserved on a host-local not-found: %v", err)
+	}
+}
+
+// TestReconcileSessionsOnStartup_FailedNonResumableDeadRowPrunedOnNotFound
+// extends the classification to the non-resumable FAILED startup path: a failed
+// session with no resume handle whose dead-local runtime returns not-found must
+// have its row pruned rather than preserved with the "failed to stop failed
+// session runtime; preserving executor record" warning.
+func TestReconcileSessionsOnStartup_FailedNonResumableDeadRowPrunedOnNotFound(t *testing.T) {
+	repo := setupTestRepo(t)
+	ctx := context.Background()
+	now := time.Now().UTC()
+
+	seedTaskAndSession(t, repo, "taskFail", "sFail", models.TaskSessionStateFailed)
+	if err := repo.UpsertExecutorRunning(ctx, &models.ExecutorRunning{
+		ID: "sFail", SessionID: "sFail", TaskID: "taskFail", Runtime: agentruntime.RuntimeStandalone,
+		Status: models.ExecutorRunningStatusRunning, AgentExecutionID: "execFail", LocalPID: 3131,
+		CreatedAt: now, UpdatedAt: now,
+	}); err != nil {
+		t.Fatalf("upsert sFail: %v", err)
+	}
+
+	agentMgr := &mockAgentManager{
+		stopAgentWithReasonErr: fmt.Errorf("stop agent: %w", runtimeapi.ErrNotFound),
+		rowLivenessFn: func(*models.ExecutorRunning) models.ProcessLiveness {
+			return models.ProcessLivenessDead
+		},
+	}
+	svc := createTestServiceWithAgent(repo, newMockStepGetter(), newMockTaskRepo(), agentMgr)
+	svc.reconcileSessionsOnStartup(ctx)
+
+	if _, err := repo.GetExecutorRunningBySessionID(ctx, "sFail"); err == nil {
+		t.Error("confirmed-dead non-resumable failed row with a not-found stop must be pruned, not preserved")
+	}
+}
+
+// TestReconcileSessionsOnStartup_TerminalNonNotFoundPreserved guards the
+// retryable-failure rule for the terminal path: a stop that fails with a
+// non-not-found error must preserve the row even when the row is confirmed dead.
+func TestReconcileSessionsOnStartup_TerminalNonNotFoundPreserved(t *testing.T) {
+	repo := setupTestRepo(t)
+	ctx := context.Background()
+	now := time.Now().UTC()
+
+	seedTaskAndSession(t, repo, "taskTE", "sTE", models.TaskSessionStateCompleted)
+	if err := repo.UpsertExecutorRunning(ctx, &models.ExecutorRunning{
+		ID: "sTE", SessionID: "sTE", TaskID: "taskTE", Runtime: agentruntime.RuntimeStandalone,
+		Status: models.ExecutorRunningStatusRunning, AgentExecutionID: "execTE", LocalPID: 4141,
+		CreatedAt: now, UpdatedAt: now,
+	}); err != nil {
+		t.Fatalf("upsert sTE: %v", err)
+	}
+
+	agentMgr := &mockAgentManager{
+		stopAgentWithReasonErr: errWorkTransient, // not a not-found sentinel
+		rowLivenessFn: func(*models.ExecutorRunning) models.ProcessLiveness {
+			return models.ProcessLivenessDead
+		},
+	}
+	svc := createTestServiceWithAgent(repo, newMockStepGetter(), newMockTaskRepo(), agentMgr)
+	svc.reconcileSessionsOnStartup(ctx)
+
+	if _, err := repo.GetExecutorRunningBySessionID(ctx, "sTE"); err != nil {
+		t.Errorf("a non-not-found stop failure must preserve the terminal row for retry: %v", err)
+	}
+}
diff --git a/apps/backend/internal/orchestrator/service.go b/apps/backend/internal/orchestrator/service.go
index e3dd1e4c27..36a18627c7 100644
--- a/apps/backend/internal/orchestrator/service.go
+++ b/apps/backend/internal/orchestrator/service.go
@@ -22,6 +22,7 @@ import (
 
 	"go.uber.org/zap"
 
+	runtimeapi "github.com/kandev/kandev/internal/agent/runtime"
 	"github.com/kandev/kandev/internal/agent/runtime/routingerr"
 	"github.com/kandev/kandev/internal/agentctl/types/streams"
 	"github.com/kandev/kandev/internal/common/logger"
@@ -1740,11 +1741,25 @@ func (s *Service) handleMissingSessionOnStartup(ctx context.Context, running *mo
 		return
 	}
 	if err := s.agentManager.StopAgentWithReason(ctx, executionID, "startup missing session cleanup", true); err != nil {
-		s.logger.Warn("failed to stop missing-session runtime; preserving executor record",
+		// A not-found stop for a runtime whose row is a confirmed-dead LOCAL
+		// process means the runtime is already gone — treat it as an idempotent
+		// successful stop and prune/repair the row under the resume-safety
+		// invariant, so the orphan row does not survive restarts forever. Any
+		// other error (alive/unknown/remote row, or a non-not-found failure) is
+		// preserved and left for a later attempt.
+		if !stopReportsRuntimeAbsent(err) || s.rowLiveness(running) != models.ProcessLivenessDead {
+			s.logger.Warn("failed to stop missing-session runtime; preserving executor record",
+				zap.String("session_id", sessionID),
+				zap.String("task_id", running.TaskID),
+				zap.String("execution_id", executionID),
+				zap.Error(err))
+			return
+		}
+		s.logger.Info("missing-session runtime already gone (confirmed dead); pruning executor record",
 			zap.String("session_id", sessionID),
 			zap.String("task_id", running.TaskID),
-			zap.String("execution_id", executionID),
-			zap.Error(err))
+			zap.String("execution_id", executionID))
+		s.pruneOrRepairExecutorRow(ctx, running, models.TaskSessionStateCancelled)
 		return
 	}
 	if err := s.repo.DeleteExecutorRunningBySessionID(ctx, sessionID); err != nil {
@@ -1755,6 +1770,17 @@ func (s *Service) handleMissingSessionOnStartup(ctx context.Context, running *mo
 	}
 }
 
+// stopReportsRuntimeAbsent reports whether a stop error means the runtime is
+// already gone (a typed not-found sentinel), as opposed to a transient failure.
+// Only a typed sentinel counts — a generic store/lookup error must never be
+// reinterpreted as an absent runtime. The runtime seam (lifecycleAdapter)
+// normalizes the backend lifecycle not-found sentinel to runtimeapi.ErrNotFound,
+// so reconciliation depends only on the public runtime and executor sentinels.
+func stopReportsRuntimeAbsent(err error) bool {
+	return errors.Is(err, runtimeapi.ErrNotFound) ||
+		errors.Is(err, executor.ErrExecutionNotFound)
+}
+
 func (s *Service) abandonOpenTurnsOnStartup(ctx context.Context, sessionID, reason string) {
 	if s.turnService == nil {
 		return
@@ -1783,15 +1809,8 @@ func (s *Service) handleTerminalSessionOnStartup(ctx context.Context, session *m
 			zap.String("task_id", session.TaskID),
 			zap.String("state", string(previousState)))
 		s.abandonOpenTurnsOnStartup(ctx, sessionID, "terminal session cleanup")
-		executionID := strings.TrimSpace(running.AgentExecutionID)
-		if executionID != "" && s.agentManager != nil {
-			if err := s.agentManager.StopAgentWithReason(ctx, executionID, "startup terminal session cleanup", true); err != nil {
-				s.logger.Warn("failed to stop terminal session runtime; preserving executor record",
-					zap.String("session_id", sessionID),
-					zap.String("execution_id", executionID),
-					zap.Error(err))
-				return true
-			}
+		if !s.stopRuntimeForStartupCleanup(ctx, running, "startup terminal session cleanup") {
+			return true
 		}
 		// Resume-safety invariant: prune the row only if it is not still resumable
 		// (no resume_token). A terminal session that kept a resume_token — e.g. an
@@ -1835,15 +1854,8 @@ func (s *Service) handleFailedSessionOnStartup(ctx context.Context, session *mod
 		s.logger.Info("stopping failed session runtime before cleaning up executor record",
 			zap.String("session_id", sessionID),
 			zap.String("task_id", session.TaskID))
-		executionID := strings.TrimSpace(running.AgentExecutionID)
-		if executionID != "" && s.agentManager != nil {
-			if err := s.agentManager.StopAgentWithReason(ctx, executionID, "startup failed session cleanup", true); err != nil {
-				s.logger.Warn("failed to stop failed session runtime; preserving executor record",
-					zap.String("session_id", sessionID),
-					zap.String("execution_id", executionID),
-					zap.Error(err))
-				return
-			}
+		if !s.stopRuntimeForStartupCleanup(ctx, running, "startup failed session cleanup") {
+			return
 		}
 		// Prune only subject to the resume-safety invariant (a lingering
 		// resume_token is repaired in place rather than deleted).
@@ -1851,6 +1863,40 @@ func (s *Service) handleFailedSessionOnStartup(ctx context.Context, session *mod
 	}
 }
 
+// stopRuntimeForStartupCleanup stops a session's still-registered runtime handle
+// during startup reconciliation and reports whether the caller may proceed to
+// prune/repair the executor row. It mirrors handleMissingSessionOnStartup's
+// classification so terminal and non-resumable-failed reconciliation stop
+// leaking stale rows: a not-found stop for a confirmed-dead LOCAL runtime means
+// the runtime is already gone and cleanup proceeds; any other error
+// (alive/unknown/remote row, or a non-not-found failure) preserves the row for a
+// later attempt. A row with no stoppable handle is already stoppable-complete.
+func (s *Service) stopRuntimeForStartupCleanup(ctx context.Context, running *models.ExecutorRunning, reason string) bool {
+	executionID := strings.TrimSpace(running.AgentExecutionID)
+	if executionID == "" || s.agentManager == nil {
+		return true
+	}
+	err := s.agentManager.StopAgentWithReason(ctx, executionID, reason, true)
+	if err == nil {
+		return true
+	}
+	if !stopReportsRuntimeAbsent(err) || s.rowLiveness(running) != models.ProcessLivenessDead {
+		s.logger.Warn("failed to stop session runtime during startup cleanup; preserving executor record",
+			zap.String("session_id", running.SessionID),
+			zap.String("task_id", running.TaskID),
+			zap.String("execution_id", executionID),
+			zap.String("reason", reason),
+			zap.Error(err))
+		return false
+	}
+	s.logger.Info("session runtime already gone (confirmed dead) during startup cleanup; proceeding to prune/repair",
+		zap.String("session_id", running.SessionID),
+		zap.String("task_id", running.TaskID),
+		zap.String("execution_id", executionID),
+		zap.String("reason", reason))
+	return true
+}
+
 func canResumeRunning(running *models.ExecutorRunning) bool {
 	if running == nil || running.ResumeToken == "" {
 		return false
diff --git a/apps/backend/internal/orchestrator/watcher_dispatch.go b/apps/backend/internal/orchestrator/watcher_dispatch.go
index 0c753e9aef..4b9c0373ca 100644
--- a/apps/backend/internal/orchestrator/watcher_dispatch.go
+++ b/apps/backend/internal/orchestrator/watcher_dispatch.go
@@ -8,6 +8,7 @@ import (
 	"go.uber.org/zap"
 
 	"github.com/kandev/kandev/internal/common/logger"
+	"github.com/kandev/kandev/internal/task/service"
 	workflowmodels "github.com/kandev/kandev/internal/workflow/models"
 )
 
@@ -349,6 +350,16 @@ func (c *WatcherDispatchCoordinator) Dispatch(ctx context.Context, src WatcherSo
 		return
 	}
 
+	// Bound the generated title once, here, so every watcher source (Linear,
+	// Jira, GitLab, future) inherits the task-title limit without each
+	// BuildTaskRequest re-implementing truncation. A remote issue title that
+	// would otherwise exceed the limit is shortened rather than rejected by
+	// backend title validation. GitHub's review/issue path builds its tasks
+	// through a separate creator and truncates at its own builders.
+	if req != nil {
+		req.Title = service.TruncateTaskTitle(req.Title)
+	}
+
 	// A bound repository deleted after the watch was configured would let
 	// CreateTask insert a task row before repository association fails. Self-heal
 	// and release the reservation instead of creating an orphan task.
diff --git a/apps/backend/internal/orchestrator/watcher_dispatch_test.go b/apps/backend/internal/orchestrator/watcher_dispatch_test.go
index 6375127f65..08fa463cb8 100644
--- a/apps/backend/internal/orchestrator/watcher_dispatch_test.go
+++ b/apps/backend/internal/orchestrator/watcher_dispatch_test.go
@@ -3,12 +3,15 @@ package orchestrator
 import (
 	"context"
 	"errors"
+	"strings"
 	"testing"
+	"unicode/utf8"
 
 	"go.uber.org/zap"
 
 	"github.com/kandev/kandev/internal/common/logger"
 	"github.com/kandev/kandev/internal/task/models"
+	"github.com/kandev/kandev/internal/task/service"
 	workflowmodels "github.com/kandev/kandev/internal/workflow/models"
 )
 
@@ -182,6 +185,68 @@ func TestCoordinator_Dispatch_HappyPath(t *testing.T) {
 	}
 }
 
+// TestCoordinator_Dispatch_TruncatesOverlongTitle pins the watcher-wide title
+// guarantee: any WatcherSource (Linear, Jira, GitLab, future) whose
+// BuildTaskRequest returns an overlong Title has that title bounded to the task
+// title limit by the coordinator before CreateIssueTask, so a long remote issue
+// title is never rejected by backend title validation.
+func TestCoordinator_Dispatch_TruncatesOverlongTitle(t *testing.T) {
+	longTitle := "[ENG-1] " + strings.Repeat("x", 200)
+	src := &fakeWatcherSource{
+		name:      "linear",
+		reserveOK: true,
+		buildReq: &IssueTaskRequest{
+			WorkspaceID:    "ws-1",
+			WorkflowStepID: "step-1",
+			Title:          longTitle,
+			Description:    "body",
+		},
+	}
+	tc := &fakeTaskCreator{}
+	starter := &fakeTaskStarter{}
+	c := newTestCoordinator(t, tc, false, starter)
+
+	c.Dispatch(context.Background(), src, "evt")
+
+	if tc.gotReq == nil {
+		t.Fatal("expected task creator to receive the built request")
+	}
+	got := tc.gotReq.Title
+	if runes := utf8.RuneCountInString(got); runes > service.TaskTitleMaxLength {
+		t.Fatalf("title not truncated: %d runes (limit %d): %q", runes, service.TaskTitleMaxLength, got)
+	}
+	if !utf8.ValidString(got) {
+		t.Fatalf("truncated title is not valid UTF-8: %q", got)
+	}
+	if !strings.HasPrefix(got, "[ENG-1] ") {
+		t.Fatalf("truncation dropped the source prefix: %q", got)
+	}
+}
+
+// TestCoordinator_Dispatch_KeepsShortTitleUnchanged confirms the truncation is a
+// no-op for a title already within the limit — the coordinator does not append an
+// ellipsis or otherwise rewrite a compliant title.
+func TestCoordinator_Dispatch_KeepsShortTitleUnchanged(t *testing.T) {
+	src := &fakeWatcherSource{
+		name:      "jira",
+		reserveOK: true,
+		buildReq: &IssueTaskRequest{
+			WorkspaceID:    "ws-1",
+			WorkflowStepID: "step-1",
+			Title:          "[PROJ-7] short enough",
+			Description:    "body",
+		},
+	}
+	tc := &fakeTaskCreator{}
+	c := newTestCoordinator(t, tc, false, &fakeTaskStarter{})
+
+	c.Dispatch(context.Background(), src, "evt")
+
+	if tc.gotReq == nil || tc.gotReq.Title != "[PROJ-7] short enough" {
+		t.Fatalf("expected short title unchanged, got %+v", tc.gotReq)
+	}
+}
+
 func TestCoordinator_Dispatch_ReserveLost(t *testing.T) {
 	src := &fakeWatcherSource{name: "linear", reserveOK: false}
 	tc := &fakeTaskCreator{}
diff --git a/apps/backend/internal/repoclone/clone_auth_test.go b/apps/backend/internal/repoclone/clone_auth_test.go
index 3d7b00b0f9..84f70f53aa 100644
--- a/apps/backend/internal/repoclone/clone_auth_test.go
+++ b/apps/backend/internal/repoclone/clone_auth_test.go
@@ -50,8 +50,8 @@ func TestEnsureWorkspaceClonedWithBasicAuthKeepsCredentialScopedToGitChild(t *te
 	}
 	for _, tc := range tests {
 		t.Run(tc.name, func(t *testing.T) {
-			binDir := t.TempDir()
-			capturePath := filepath.Join(t.TempDir(), "git-env")
+			binDir := canonicalTempDir(t)
+			capturePath := filepath.Join(canonicalTempDir(t), "git-env")
 			fakeGit := "#!/bin/sh\nprintf '%s\\n%s' \"$GIT_CONFIG_KEY_1\" \"$GIT_CONFIG_VALUE_1\" > \"$CAPTURE_PATH\"\n" +
 				"if [ \"$BLOCK_GIT\" = 1 ]; then exec sleep 10; fi\nexit 1\n"
 			if err := os.WriteFile(filepath.Join(binDir, "git"), []byte(fakeGit), 0o755); err != nil {
@@ -63,11 +63,14 @@ func TestEnsureWorkspaceClonedWithBasicAuthKeepsCredentialScopedToGitChild(t *te
 			if tc.cancel {
 				t.Setenv("BLOCK_GIT", "1")
 			}
-			cloner := NewCloner(Config{BasePath: t.TempDir()}, ProtocolHTTPS, "", logger.Default())
+			cloner := NewCloner(Config{BasePath: canonicalTempDir(t)}, ProtocolHTTPS, "", logger.Default())
 			ctx := context.Background()
 			var cancel context.CancelFunc
 			if tc.cancel {
-				ctx, cancel = context.WithTimeout(ctx, 20*time.Millisecond)
+				// Generous enough for a cold shell start (macOS is slow) so the
+				// fake git reliably writes CAPTURE_PATH before entering its long
+				// sleep; the deadline then cancels the blocked clone mid-run.
+				ctx, cancel = context.WithTimeout(ctx, 750*time.Millisecond)
 				defer cancel()
 			}
 			targetPath, err := cloner.EnsureWorkspaceClonedWithBasicAuth(
@@ -102,3 +105,14 @@ func TestEnsureWorkspaceClonedWithBasicAuthKeepsCredentialScopedToGitChild(t *te
 		})
 	}
 }
+
+// canonicalTempDir returns t.TempDir() with symlinks resolved so the Git child
+// and the assertions agree on paths (macOS /var -> /private/var).
+func canonicalTempDir(t *testing.T) string {
+	t.Helper()
+	resolved, err := filepath.EvalSymlinks(t.TempDir())
+	if err != nil {
+		t.Fatal(err)
+	}
+	return resolved
+}
diff --git a/apps/backend/internal/scheduler/cron/routines.go b/apps/backend/internal/scheduler/cron/routines.go
index c8feeb8c8e..e194cf8fb0 100644
--- a/apps/backend/internal/scheduler/cron/routines.go
+++ b/apps/backend/internal/scheduler/cron/routines.go
@@ -2,6 +2,7 @@ package cron
 
 import (
 	"context"
+	"reflect"
 	"time"
 
 	"go.uber.org/zap"
@@ -36,10 +37,18 @@ type RoutinesHandler struct {
 
 // NewRoutinesHandler builds a RoutinesHandler. now defaults to
 // time.Now().UTC() when nil — tests pass a controlled clock.
+//
+// A typed-nil collaborator (a concrete nil pointer assigned into the
+// RoutineTicker interface, as happens when Office is disabled) is
+// normalised to a genuinely nil interface so Tick takes the no-op branch
+// instead of dereferencing a nil receiver.
 func NewRoutinesHandler(ticker RoutineTicker, now func() time.Time, log *logger.Logger) *RoutinesHandler {
 	if now == nil {
 		now = func() time.Time { return time.Now().UTC() }
 	}
+	if isNilTicker(ticker) {
+		ticker = nil
+	}
 	return &RoutinesHandler{
 		ticker: ticker,
 		now:    now,
@@ -47,6 +56,25 @@ func NewRoutinesHandler(ticker RoutineTicker, now func() time.Time, log *logger.
 	}
 }
 
+// isNilTicker reports whether ticker is absent, treating a typed-nil
+// pointer wrapped in the interface the same as a genuinely nil interface.
+func isNilTicker(ticker RoutineTicker) bool {
+	if ticker == nil {
+		return true
+	}
+	// Every RoutineTicker implementation today is a pointer receiver, so Ptr is
+	// the only kind reached in practice; the remaining nil-able kinds are listed
+	// defensively so a future value/func/channel implementer can never smuggle a
+	// typed-nil past this guard and re-open the Office-disabled tick panic.
+	v := reflect.ValueOf(ticker)
+	switch v.Kind() {
+	case reflect.Ptr, reflect.Map, reflect.Chan, reflect.Func, reflect.Slice, reflect.Interface:
+		return v.IsNil()
+	default:
+		return false
+	}
+}
+
 // Name implements Handler.
 func (h *RoutinesHandler) Name() string { return "routines" }
 
diff --git a/apps/backend/internal/scheduler/cron/routines_test.go b/apps/backend/internal/scheduler/cron/routines_test.go
index 9a251cea26..15b1c9a2f7 100644
--- a/apps/backend/internal/scheduler/cron/routines_test.go
+++ b/apps/backend/internal/scheduler/cron/routines_test.go
@@ -54,3 +54,18 @@ func TestRoutinesHandler_NilTickerIsNoOp(t *testing.T) {
 		t.Fatalf("Tick: %v", err)
 	}
 }
+
+// TestRoutinesHandler_TypedNilTickerIsNoOp reproduces the Office-disabled
+// regression: a concrete nil pointer assigned into the RoutineTicker
+// interface is a non-nil interface value, so a naive h.ticker == nil guard
+// is bypassed and Tick dereferences the nil receiver. A handler built from a
+// typed-nil collaborator by any wiring path must no-op instead of panicking.
+func TestRoutinesHandler_TypedNilTickerIsNoOp(t *testing.T) {
+	var typedNil *fakeRoutineTicker
+	var ticker RoutineTicker = typedNil // non-nil interface wrapping a nil pointer
+
+	h := NewRoutinesHandler(ticker, nil, logger.Default())
+	if err := h.Tick(context.Background()); err != nil {
+		t.Fatalf("Tick: %v", err)
+	}
+}
diff --git a/apps/backend/internal/task/handlers/repository_handlers_test.go b/apps/backend/internal/task/handlers/repository_handlers_test.go
index 73cbb9851e..658f042b2f 100644
--- a/apps/backend/internal/task/handlers/repository_handlers_test.go
+++ b/apps/backend/internal/task/handlers/repository_handlers_test.go
@@ -55,7 +55,7 @@ func TestHTTPCreateRepositoryRejectsInvalidLocalPathWithoutPersistence(t *testin
 
 func TestHTTPInitializeLocalRepositoryCreatesRepository(t *testing.T) {
 	router, repo := newRepositoryHTTPTestRouter(t)
-	parentPath := t.TempDir()
+	parentPath := canonicalTempDir(t)
 	body := []byte(`{"name":"new-project","parent_path":` + strconv.Quote(parentPath) + `}`)
 	request := httptest.NewRequest(
 		http.MethodPost,
@@ -316,7 +316,7 @@ func TestHTTPListDirectoryIncludesChoosableContract(t *testing.T) {
 
 func TestHTTPCreateDirectoryCreatesFolder(t *testing.T) {
 	router, _ := newRepositoryHTTPTestRouter(t)
-	parent := t.TempDir()
+	parent := canonicalTempDir(t)
 	request := httptest.NewRequest(
 		http.MethodPost,
 		"/api/v1/fs/create-dir",
diff --git a/apps/backend/internal/task/handlers/task_http_handlers_test.go b/apps/backend/internal/task/handlers/task_http_handlers_test.go
index 01bf6ab8e1..8c8c5f8135 100644
--- a/apps/backend/internal/task/handlers/task_http_handlers_test.go
+++ b/apps/backend/internal/task/handlers/task_http_handlers_test.go
@@ -1597,8 +1597,8 @@ func (r *freshBranchIdentityRepository) CreateTaskRepository(_ context.Context,
 
 func TestCommitFreshBranchUsesPersistedTaskRepositoryIdentity(t *testing.T) {
 	gin.SetMode(gin.TestMode)
-	realRepoPath := initHandlerGitRepository(t, filepath.Join(t.TempDir(), "real"))
-	decoyRepoPath := initHandlerGitRepository(t, filepath.Join(t.TempDir(), "decoy"))
+	realRepoPath := initHandlerGitRepository(t, filepath.Join(canonicalTempDir(t), "real"))
+	decoyRepoPath := initHandlerGitRepository(t, filepath.Join(canonicalTempDir(t), "decoy"))
 	repo := &freshBranchIdentityRepository{
 		task: &models.Task{ID: "task-1", WorkspaceID: "ws-1"},
 		taskRepos: []*models.TaskRepository{{
@@ -1667,6 +1667,16 @@ func TestCommitFreshBranchRollsBackTaskWhenPersistedRepositoriesCannotBeLoaded(t
 	}
 }
 
+// canonicalTempDir returns t.TempDir() with symlinks resolved, matching how production canonicalizes local paths.
+func canonicalTempDir(t *testing.T) string {
+	t.Helper()
+	resolved, err := filepath.EvalSymlinks(t.TempDir())
+	if err != nil {
+		t.Fatalf("EvalSymlinks: %v", err)
+	}
+	return resolved
+}
+
 func initHandlerGitRepository(t *testing.T, path string) string {
 	t.Helper()
 	if err := os.MkdirAll(path, 0o755); err != nil {
diff --git a/apps/backend/internal/task/service/fresh_branch_test.go b/apps/backend/internal/task/service/fresh_branch_test.go
index 39d1f68d33..911bb8e3b7 100644
--- a/apps/backend/internal/task/service/fresh_branch_test.go
+++ b/apps/backend/internal/task/service/fresh_branch_test.go
@@ -310,6 +310,22 @@ func TestLocalRepositoryStatus_ListsDirtyFiles(t *testing.T) {
 }
 
 // initRealGitRepo creates a git repo with a single commit on `main`.
+// canonicalRepoTestPath resolves dir the same way the production
+// CreateRepository path does (filepath.EvalSymlinks), so a stored LocalPath
+// matches what resolveRepositoryLocalPath re-resolves it to. Tests that write
+// LocalPath through the repository-entity layer directly (bypassing the
+// canonicalizing service.CreateRepository) must use this, or the saved raw
+// t.TempDir() path fails the sameCanonicalPath guard on platforms whose temp
+// dir has a symlinked ancestor (e.g. macOS /var -> /private/var).
+func canonicalRepoTestPath(t *testing.T, dir string) string {
+	t.Helper()
+	resolved, err := filepath.EvalSymlinks(dir)
+	if err != nil {
+		t.Fatalf("EvalSymlinks(%q): %v", dir, err)
+	}
+	return resolved
+}
+
 func initRealGitRepo(t *testing.T, dir string) {
 	t.Helper()
 	if err := os.MkdirAll(dir, 0o755); err != nil {
@@ -388,7 +404,7 @@ func persistFreshBranchRepository(t *testing.T, svc *Service, repoPath string) s
 		t.Fatalf("CreateWorkspace: %v", err)
 	}
 	if err := svc.repoEntities.CreateRepository(ctx, &models.Repository{
-		ID: repositoryID, WorkspaceID: workspaceID, Name: "Repository", SourceType: sourceTypeLocal, LocalPath: repoPath,
+		ID: repositoryID, WorkspaceID: workspaceID, Name: "Repository", SourceType: sourceTypeLocal, LocalPath: canonicalRepoTestPath(t, repoPath),
 	}); err != nil {
 		t.Fatalf("CreateRepository: %v", err)
 	}
diff --git a/apps/backend/internal/task/service/repository_discovery_test.go b/apps/backend/internal/task/service/repository_discovery_test.go
index 2c12a2421e..b890ff05e8 100644
--- a/apps/backend/internal/task/service/repository_discovery_test.go
+++ b/apps/backend/internal/task/service/repository_discovery_test.go
@@ -747,7 +747,7 @@ func TestListBranches_SavedRepositoryOutsideDiscoveryRoots(t *testing.T) {
 		t.Fatalf("CreateWorkspace: %v", err)
 	}
 	if err := svc.repoEntities.CreateRepository(ctx, &models.Repository{
-		ID: "outside-repo", WorkspaceID: "ws-1", Name: "outside", SourceType: sourceTypeLocal, LocalPath: repoPath,
+		ID: "outside-repo", WorkspaceID: "ws-1", Name: "outside", SourceType: sourceTypeLocal, LocalPath: canonicalRepoTestPath(t, repoPath),
 	}); err != nil {
 		t.Fatalf("CreateRepository: %v", err)
 	}
@@ -848,7 +848,7 @@ func TestListBranches_SavedLinkedWorktreeOutsideDiscoveryRoots(t *testing.T) {
 		t.Fatalf("CreateWorkspace: %v", err)
 	}
 	if err := svc.repoEntities.CreateRepository(ctx, &models.Repository{
-		ID: "linked-repo", WorkspaceID: "ws-1", Name: "linked", SourceType: sourceTypeLocal, LocalPath: linkedPath,
+		ID: "linked-repo", WorkspaceID: "ws-1", Name: "linked", SourceType: sourceTypeLocal, LocalPath: canonicalRepoTestPath(t, linkedPath),
 	}); err != nil {
 		t.Fatalf("CreateRepository: %v", err)
 	}
diff --git a/apps/backend/internal/task/service/repository_fetch_test.go b/apps/backend/internal/task/service/repository_fetch_test.go
index 134e1534dc..9b2e1fdb9b 100644
--- a/apps/backend/internal/task/service/repository_fetch_test.go
+++ b/apps/backend/internal/task/service/repository_fetch_test.go
@@ -153,7 +153,7 @@ func TestRefreshRepositoryBranches_SavedRepositoryOutsideDiscoveryRoots(t *testi
 		t.Fatalf("CreateWorkspace: %v", err)
 	}
 	if err := svc.repoEntities.CreateRepository(ctx, &models.Repository{
-		ID: "outside-repo", WorkspaceID: "ws-1", Name: "outside", SourceType: sourceTypeLocal, LocalPath: repoPath,
+		ID: "outside-repo", WorkspaceID: "ws-1", Name: "outside", SourceType: sourceTypeLocal, LocalPath: canonicalRepoTestPath(t, repoPath),
 	}); err != nil {
 		t.Fatalf("CreateRepository: %v", err)
 	}
diff --git a/apps/backend/internal/task/service/resource_cleanup_jobs.go b/apps/backend/internal/task/service/resource_cleanup_jobs.go
index 2211201cee..15fbad51da 100644
--- a/apps/backend/internal/task/service/resource_cleanup_jobs.go
+++ b/apps/backend/internal/task/service/resource_cleanup_jobs.go
@@ -393,12 +393,14 @@ func (s *Service) executeTaskResourceCleanupJob(
 		return fmt.Errorf("refresh task cleanup runtime inventory: %w", err)
 	}
 	s.registerTaskRuntimeStopOwners(targets, true)
-	failedStops := s.stopTaskRuntimeTargets(ctx, job.TaskID, targets, taskResourceCleanupStopReason(job.Trigger), "task cleanup runtime stop failed")
+	stopOutcome := s.stopTaskRuntimeTargets(ctx, job.TaskID, targets, taskResourceCleanupStopReason(job.Trigger), "task cleanup runtime stop failed")
+	failedStops := stopOutcome.failed
 	if cancelled, err := s.cancelIfTaskUnarchived(ctx, job); err != nil || cancelled {
 		return err
 	}
 	errs := s.performTaskCleanup(ctx, job.TaskID, snapshot.Sessions, snapshot.Worktrees, targets,
-		taskEnvironmentCleanup{env: snapshot.TaskEnvironment, deleteRow: snapshot.DeleteEnvironmentRow}, failedStops)
+		taskEnvironmentCleanup{env: snapshot.TaskEnvironment, deleteRow: snapshot.DeleteEnvironmentRow},
+		taskCleanupPreserveRows(stopOutcome))
 	if cause := context.Cause(ctx); cause != nil {
 		return errors.Join(append(errs, cause)...)
 	}
diff --git a/apps/backend/internal/task/service/service.go b/apps/backend/internal/task/service/service.go
index 5fd9bb715b..2e8bc0a984 100644
--- a/apps/backend/internal/task/service/service.go
+++ b/apps/backend/internal/task/service/service.go
@@ -53,6 +53,15 @@ type TaskExecutionStopper interface {
 	RegisterExecutionStopOwner(sessionID, executionID string, force bool)
 }
 
+// TaskRowLivenessProber classifies an executors_running row's backing-process
+// liveness in a runtime-aware way (a local process check is never applied to a
+// remote/SSH row). It is optional and satisfied by the lifecycle adapter. When
+// unwired, cleanup treats every row as Unknown so a not-found stop is never
+// mistaken for an absent runtime.
+type TaskRowLivenessProber interface {
+	RowLiveness(row *models.ExecutorRunning) models.ProcessLiveness
+}
+
 // TaskResourceCleanupActivityGate serializes durable cleanup with install-wide maintenance.
 type TaskResourceCleanupActivityGate interface {
 	AcquireTaskResourceCleanup(context.Context) (TaskResourceCleanupActivityLease, error)
@@ -243,6 +252,7 @@ type Service struct {
 	discoveryConfig             RepositoryDiscoveryConfig
 	worktreeCleanup             WorktreeCleanup
 	executionStopper            TaskExecutionStopper
+	rowLivenessProber           TaskRowLivenessProber
 	contextWindowResetter       func(context.Context, string) error
 	cleanupActivity             TaskResourceCleanupActivityGate
 	branchMaterializer          BranchMaterializer
@@ -371,6 +381,13 @@ func (s *Service) SetExecutionStopper(stopper TaskExecutionStopper) {
 	s.executionStopper = stopper
 }
 
+// SetRowLivenessProber wires the runtime-aware executors_running liveness probe
+// (satisfied by the lifecycle adapter). It is optional; when unwired, cleanup
+// treats every row as Unknown.
+func (s *Service) SetRowLivenessProber(prober TaskRowLivenessProber) {
+	s.rowLivenessProber = prober
+}
+
 // SetContextWindowResetter wires the guarded context-window reset callback
 // owned by the orchestrator. It is optional for isolated task-service users;
 // those callers fall back to clearing the session metadata directly.
diff --git a/apps/backend/internal/task/service/service_tasks.go b/apps/backend/internal/task/service/service_tasks.go
index 1c705e8c37..8a5df8004e 100644
--- a/apps/backend/internal/task/service/service_tasks.go
+++ b/apps/backend/internal/task/service/service_tasks.go
@@ -1980,9 +1980,10 @@ func (s *Service) runTaskCleanup(
 	stopTargets = refreshedTargets
 	s.registerTaskRuntimeStopOwners(stopTargets, true)
 
-	failedStops := s.stopTaskRuntimeTargets(cleanupCtx, id, stopTargets, stopReason, stopFailMsg)
+	stopOutcome := s.stopTaskRuntimeTargets(cleanupCtx, id, stopTargets, stopReason, stopFailMsg)
 
-	cleanupErrors := s.performTaskCleanup(cleanupCtx, id, sessions, worktrees, stopTargets, envCleanup, failedStops)
+	cleanupErrors := s.performTaskCleanup(cleanupCtx, id, sessions, worktrees, stopTargets, envCleanup,
+		taskCleanupPreserveRows(stopOutcome))
 
 	if len(cleanupErrors) > 0 {
 		s.logger.Warn(cleanupMsg+" with errors",
@@ -2153,14 +2154,46 @@ func exactTaskStopTargetSessions(targetSets ...[]taskStopTarget) map[string]stru
 	return exact
 }
 
-func (s *Service) stopTaskRuntimeTargets(ctx context.Context, taskID string, stopTargets []taskStopTarget, stopReason, stopFailMsg string) map[string]struct{} {
-	failedStops := make(map[string]struct{})
+// taskRuntimeStopOutcome separates the two independent effects a stop pass has on
+// downstream cleanup. failed drives durable-job retry accounting AND row
+// preservation (a still-uncertain stop must be retried and its row kept).
+// preserve keeps a row (and its worktree) from being torn down WITHOUT counting
+// as a retryable failure — used for a confirmed-dead but resume-safe row that was
+// repaired in place under the resume-safety invariant.
+type taskRuntimeStopOutcome struct {
+	failed   map[string]struct{}
+	preserve map[string]struct{}
+}
+
+// taskCleanupPreserveRows is the set of sessions whose executor row and worktree
+// must survive this cleanup pass: every failed (retryable) stop plus every
+// resume-safe row repaired in place. performTaskCleanup treats membership as
+// "do not delete this row/worktree".
+func taskCleanupPreserveRows(outcome taskRuntimeStopOutcome) map[string]struct{} {
+	if len(outcome.preserve) == 0 {
+		return outcome.failed
+	}
+	preserve := make(map[string]struct{}, len(outcome.failed)+len(outcome.preserve))
+	for id := range outcome.failed {
+		preserve[id] = struct{}{}
+	}
+	for id := range outcome.preserve {
+		preserve[id] = struct{}{}
+	}
+	return preserve
+}
+
+func (s *Service) stopTaskRuntimeTargets(ctx context.Context, taskID string, stopTargets []taskStopTarget, stopReason, stopFailMsg string) taskRuntimeStopOutcome {
+	outcome := taskRuntimeStopOutcome{
+		failed:   make(map[string]struct{}),
+		preserve: make(map[string]struct{}),
+	}
 	if s.executionStopper == nil || len(stopTargets) == 0 {
-		return failedStops
+		return outcome
 	}
 	for _, target := range stopTargets {
 		if context.Cause(ctx) != nil {
-			return failedStops
+			return outcome
 		}
 		if target.executionID != "" {
 			if err := s.executionStopper.StopExecution(ctx, target.executionID, stopReason, true); err != nil {
@@ -2174,7 +2207,7 @@ func (s *Service) stopTaskRuntimeTargets(ctx context.Context, taskID string, sto
 						zap.Error(err))
 					continue
 				}
-				failedStops[target.sessionID] = struct{}{}
+				outcome.failed[target.sessionID] = struct{}{}
 				s.logger.Warn(stopFailMsg,
 					zap.String("task_id", taskID),
 					zap.String("session_id", target.sessionID),
@@ -2191,20 +2224,95 @@ func (s *Service) stopTaskRuntimeTargets(ctx context.Context, taskID string, sto
 					zap.Error(err))
 				continue
 			}
-			failedStops[target.sessionID] = struct{}{}
+			// A session-level not-found is retryable by default (the execution may
+			// simply not be registered yet). But when the owned row is a
+			// confirmed-dead LOCAL runtime, the runtime really is gone — treat the
+			// stop as already complete so the durable cleanup job stops retrying a
+			// runtime that will never come back.
+			if runtimeStopAlreadyComplete(err) {
+				if running := s.confirmedDeadLocalRow(ctx, target.sessionID); running != nil {
+					s.reconcileConfirmedDeadRow(ctx, taskID, target.sessionID, running, &outcome)
+					continue
+				}
+			}
+			outcome.failed[target.sessionID] = struct{}{}
 			s.logger.Warn(stopFailMsg,
 				zap.String("task_id", taskID),
 				zap.String("session_id", target.sessionID),
 				zap.Error(err))
 		}
 	}
-	return failedStops
+	return outcome
+}
+
+// reconcileConfirmedDeadRow applies the resume-safety deletion invariant to a
+// confirmed-dead local row whose stop reported not-found. A row holding a
+// resume_token or backing a resumable session is repaired in place (never
+// deleted) and marked preserve-without-retry; a row that is neither is left for
+// the normal cleanup path to prune. Neither outcome is a failed stop, so the
+// durable cleanup job does not retry solely because the runtime was absent.
+func (s *Service) reconcileConfirmedDeadRow(
+	ctx context.Context,
+	taskID, sessionID string,
+	running *models.ExecutorRunning,
+	outcome *taskRuntimeStopOutcome,
+) {
+	if models.RowMustBePreserved(running, s.sessionStateForCleanup(ctx, sessionID)) {
+		outcome.preserve[sessionID] = struct{}{}
+		if err := s.executors.RepairExecutorRunningDead(ctx, sessionID); err != nil {
+			s.logger.Warn("failed to repair confirmed-dead resume-safe runtime row",
+				zap.String("task_id", taskID),
+				zap.String("session_id", sessionID),
+				zap.Error(err))
+		}
+		s.logger.Info("session runtime confirmed dead and resume-safe; repairing row in place",
+			zap.String("task_id", taskID),
+			zap.String("session_id", sessionID))
+		return
+	}
+	s.logger.Info("session runtime confirmed dead and already gone; treating stop as complete",
+		zap.String("task_id", taskID),
+		zap.String("session_id", sessionID))
+}
+
+// sessionStateForCleanup best-effort reads a session's state for the
+// resume-safety check. A missing session is treated as an empty (non-resumable)
+// state so a row's preservation then hinges on its resume_token alone.
+func (s *Service) sessionStateForCleanup(ctx context.Context, sessionID string) models.TaskSessionState {
+	if s.sessions == nil {
+		return ""
+	}
+	session, err := s.sessions.GetTaskSession(ctx, sessionID)
+	if err != nil || session == nil {
+		return ""
+	}
+	return session.State
 }
 
 func runtimeStopAlreadyComplete(err error) bool {
 	return errors.Is(err, runtimeapi.ErrNotFound)
 }
 
+// confirmedDeadLocalRow returns the executors_running row backing sessionID when
+// it is a confirmed-dead LOCAL runtime — a local process handle that no longer
+// exists on this host — and nil otherwise. It returns nil when no prober is
+// wired, the row is missing/unreadable, or the runtime-aware liveness is
+// anything other than Dead, so an alive, unknown, or remote row is never treated
+// as absent.
+func (s *Service) confirmedDeadLocalRow(ctx context.Context, sessionID string) *models.ExecutorRunning {
+	if s.rowLivenessProber == nil || s.executors == nil {
+		return nil
+	}
+	running, err := s.executors.GetExecutorRunningBySessionID(ctx, sessionID)
+	if err != nil || running == nil {
+		return nil
+	}
+	if s.rowLivenessProber.RowLiveness(running) != models.ProcessLivenessDead {
+		return nil
+	}
+	return running
+}
+
 // performTaskCleanup handles post-deletion cleanup operations.
 // Handles worktree cleanup, executor_running records, and quick-chat workspace directories.
 // Agent stopping is handled separately in the DeleteTask background goroutine.
diff --git a/apps/backend/internal/task/service/service_tasks_stop_test.go b/apps/backend/internal/task/service/service_tasks_stop_test.go
index de12e4338c..e08d5aa3ad 100644
--- a/apps/backend/internal/task/service/service_tasks_stop_test.go
+++ b/apps/backend/internal/task/service/service_tasks_stop_test.go
@@ -58,6 +58,8 @@ type stubExecutors struct {
 	runningByTaskErr error
 	runningBySession *models.ExecutorRunning
 	runningBySessErr error
+	deletedSessions  []string
+	repairedSessions []string
 }
 
 func (s *stubExecutors) ListExecutorsRunningByTaskID(_ context.Context, _ string) ([]*models.ExecutorRunning, error) {
@@ -68,7 +70,13 @@ func (s *stubExecutors) GetExecutorRunningBySessionID(_ context.Context, _ strin
 	return s.runningBySession, s.runningBySessErr
 }
 
-func (s *stubExecutors) DeleteExecutorRunningBySessionID(_ context.Context, _ string) error {
+func (s *stubExecutors) DeleteExecutorRunningBySessionID(_ context.Context, sessionID string) error {
+	s.deletedSessions = append(s.deletedSessions, sessionID)
+	return nil
+}
+
+func (s *stubExecutors) RepairExecutorRunningDead(_ context.Context, sessionID string) error {
+	s.repairedSessions = append(s.repairedSessions, sessionID)
 	return nil
 }
 
@@ -200,7 +208,7 @@ func TestRefreshTaskRuntimeStopTargets_ExactRuntimeSupersedesEmptySessionFallbac
 		targets,
 		"archive",
 		"stop failed",
-	)
+	).failed
 	if len(failed) != 0 {
 		t.Fatalf("late exact execution left retryable fallback failure: %v", failed)
 	}
@@ -270,7 +278,7 @@ func TestStopTaskRuntimeTargets_TerminalStopFailureDoesNotBlockCleanup(t *testin
 		{sessionID: "sess-cancelled", terminal: true},
 	}
 
-	failed := svc.stopTaskRuntimeTargets(context.Background(), "task-a", targets, "archive", "stop failed")
+	failed := svc.stopTaskRuntimeTargets(context.Background(), "task-a", targets, "archive", "stop failed").failed
 	if len(failed) != 0 {
 		t.Errorf("terminal stop failure must not add to failedStops; got %v", failed)
 	}
@@ -288,7 +296,7 @@ func TestStopTaskRuntimeTargets_ExactRuntimeAbsenceIsIdempotent(t *testing.T) {
 		[]taskStopTarget{{sessionID: "sess-running", executionID: "exec-running"}},
 		"archive",
 		"stop failed",
-	)
+	).failed
 	if len(failed) != 0 {
 		t.Errorf("exact runtime absence must be idempotent; got %v", failed)
 	}
@@ -306,12 +314,128 @@ func TestStopTaskRuntimeTargets_SessionRuntimeAbsenceRemainsRetryable(t *testing
 		[]taskStopTarget{{sessionID: "sess-running"}},
 		"archive",
 		"stop failed",
-	)
+	).failed
 	if _, ok := failed["sess-running"]; !ok {
 		t.Errorf("session-level absence must remain retryable; got %v", failed)
 	}
 }
 
+// stubRowLivenessProber is a minimal TaskRowLivenessProber for tests.
+type stubRowLivenessProber struct {
+	liveness models.ProcessLiveness
+}
+
+func (s stubRowLivenessProber) RowLiveness(*models.ExecutorRunning) models.ProcessLiveness {
+	return s.liveness
+}
+
+// TestStopTaskRuntimeTargets_SessionAbsenceDeadLocalIsIdempotent is the
+// regression test for the infinite cleanup-retry bug: a session-only stop that
+// returns not-found for a CONFIRMED-DEAD LOCAL row must be treated as an
+// already-stopped runtime (not a failed stop) so the durable cleanup job stops
+// retrying forever.
+func TestStopTaskRuntimeTargets_SessionAbsenceDeadLocalIsIdempotent(t *testing.T) {
+	svc, _, _ := createTestService(t)
+	execs := &stubExecutors{
+		runningBySession: &models.ExecutorRunning{
+			SessionID: "sess-dead", Runtime: agentruntime.RuntimeStandalone, LocalPID: 4242,
+		},
+	}
+	svc.executors = execs
+	svc.executionStopper = &stubStopper{
+		stopSessionErr: fmt.Errorf("gone: %w", runtimeapi.ErrNotFound),
+	}
+	svc.rowLivenessProber = stubRowLivenessProber{liveness: models.ProcessLivenessDead}
+
+	outcome := svc.stopTaskRuntimeTargets(
+		context.Background(),
+		"task-dead",
+		[]taskStopTarget{{sessionID: "sess-dead"}},
+		"archive",
+		"stop failed",
+	)
+	if len(outcome.failed) != 0 {
+		t.Errorf("session absence for a confirmed-dead local row must be idempotent; got %v", outcome.failed)
+	}
+	// A tokenless, non-resumable dead-local row is prunable: it must NOT be
+	// preserved and must NOT be repaired in place — the normal cleanup path
+	// deletes it.
+	if len(outcome.preserve) != 0 {
+		t.Errorf("tokenless dead-local row must be prunable, not preserved; got %v", outcome.preserve)
+	}
+	if len(execs.repairedSessions) != 0 {
+		t.Errorf("tokenless dead-local row must not be repaired in place; got %v", execs.repairedSessions)
+	}
+}
+
+// TestStopTaskRuntimeTargets_DeadLocalResumeSafeRowPreservedNotRetried is the
+// resume-safety regression: a confirmed-dead local row that still carries a
+// resume_token must be repaired in place (never torn down) AND excluded from the
+// retryable failedStops set, so the durable cleanup job neither retries forever
+// nor loses the only resume handle.
+func TestStopTaskRuntimeTargets_DeadLocalResumeSafeRowPreservedNotRetried(t *testing.T) {
+	svc, _, _ := createTestService(t)
+	execs := &stubExecutors{
+		runningBySession: &models.ExecutorRunning{
+			SessionID: "sess-tok", Runtime: agentruntime.RuntimeStandalone,
+			LocalPID: 4242, ResumeToken: "tok-tok",
+		},
+	}
+	svc.executors = execs
+	svc.executionStopper = &stubStopper{
+		stopSessionErr: fmt.Errorf("gone: %w", runtimeapi.ErrNotFound),
+	}
+	svc.rowLivenessProber = stubRowLivenessProber{liveness: models.ProcessLivenessDead}
+
+	outcome := svc.stopTaskRuntimeTargets(
+		context.Background(),
+		"task-tok",
+		[]taskStopTarget{{sessionID: "sess-tok"}},
+		"archive",
+		"stop failed",
+	)
+	if _, retried := outcome.failed["sess-tok"]; retried {
+		t.Errorf("resume-safe dead-local row must not be a retryable failed stop; got %v", outcome.failed)
+	}
+	if _, preserved := outcome.preserve["sess-tok"]; !preserved {
+		t.Errorf("resume-safe dead-local row must be preserved from teardown; got %v", outcome.preserve)
+	}
+	if len(execs.repairedSessions) != 1 || execs.repairedSessions[0] != "sess-tok" {
+		t.Errorf("resume-safe dead-local row must be repaired in place; got %v", execs.repairedSessions)
+	}
+	if len(execs.deletedSessions) != 0 {
+		t.Errorf("resume-safe dead-local row must never be deleted; got %v", execs.deletedSessions)
+	}
+}
+
+// TestStopTaskRuntimeTargets_SessionAbsenceUnknownRemainsRetryable guards the
+// anti-blanket-ignore rule for the cleanup worker: a session-only not-found stop
+// for a row whose liveness is Unknown (remote/no local handle) stays a failed,
+// retryable stop.
+func TestStopTaskRuntimeTargets_SessionAbsenceUnknownRemainsRetryable(t *testing.T) {
+	svc, _, _ := createTestService(t)
+	svc.executors = &stubExecutors{
+		runningBySession: &models.ExecutorRunning{
+			SessionID: "sess-remote", Runtime: agentruntime.RuntimeSSH,
+		},
+	}
+	svc.executionStopper = &stubStopper{
+		stopSessionErr: fmt.Errorf("not registered yet: %w", runtimeapi.ErrNotFound),
+	}
+	svc.rowLivenessProber = stubRowLivenessProber{liveness: models.ProcessLivenessUnknown}
+
+	failed := svc.stopTaskRuntimeTargets(
+		context.Background(),
+		"task-remote",
+		[]taskStopTarget{{sessionID: "sess-remote"}},
+		"archive",
+		"stop failed",
+	).failed
+	if _, ok := failed["sess-remote"]; !ok {
+		t.Errorf("session absence for an unknown/remote row must remain retryable; got %v", failed)
+	}
+}
+
 func TestStopTaskRuntimeTargets_NonTerminalStopFailureBlocksCleanup(t *testing.T) {
 	svc, _, _ := createTestService(t)
 	svc.executors = &stubExecutors{}
@@ -321,7 +445,7 @@ func TestStopTaskRuntimeTargets_NonTerminalStopFailureBlocksCleanup(t *testing.T
 		{sessionID: "sess-running", terminal: false},
 	}
 
-	failed := svc.stopTaskRuntimeTargets(context.Background(), "task-b", targets, "archive", "stop failed")
+	failed := svc.stopTaskRuntimeTargets(context.Background(), "task-b", targets, "archive", "stop failed").failed
 	if _, ok := failed["sess-running"]; !ok {
 		t.Error("non-terminal stop failure must add session to failedStops")
 	}
@@ -424,6 +548,90 @@ func TestCleanupTaskResources_NonTerminalSessionStopFailureBlocksCleanup(t *test
 	}
 }
 
+// seedDeadLocalSessionOnly seeds a session and a session-only executor_running
+// row (empty agent_execution_id) so cleanup takes the StopSession path rather
+// than StopExecution. resumeToken, when set, makes the row resume-safe.
+func seedDeadLocalSessionOnly(t *testing.T, repo interface {
+	CreateWorkspace(context.Context, *models.Workspace) error
+	CreateWorkflow(context.Context, *models.Workflow) error
+	CreateTask(context.Context, *models.Task) error
+	CreateTaskSession(context.Context, *models.TaskSession) error
+	UpsertExecutorRunning(context.Context, *models.ExecutorRunning) error
+}, wsID, wfID, taskID, sessID, resumeToken string, state models.TaskSessionState) {
+	t.Helper()
+	ctx := context.Background()
+	_ = repo.CreateWorkspace(ctx, &models.Workspace{ID: wsID, Name: "WS"})
+	_ = repo.CreateWorkflow(ctx, &models.Workflow{ID: wfID, WorkspaceID: wsID, Name: "WF"})
+	_ = repo.CreateTask(ctx, &models.Task{ID: taskID, WorkspaceID: wsID, WorkflowID: wfID, WorkflowStepID: "step-1", Title: "T", Priority: "medium"})
+	_ = repo.CreateTaskSession(ctx, &models.TaskSession{ID: sessID, TaskID: taskID, State: state})
+	if err := repo.UpsertExecutorRunning(ctx, &models.ExecutorRunning{
+		ID: sessID, SessionID: sessID, TaskID: taskID, ExecutorID: "executor-1",
+		Runtime: agentruntime.RuntimeStandalone, Status: models.ExecutorRunningStatusRunning,
+		LocalPID: 4242, ResumeToken: resumeToken,
+	}); err != nil {
+		t.Fatalf("seed executor_running: %v", err)
+	}
+}
+
+// TestCleanupTaskResources_NonTerminalDeadLocalSessionGetsCleanedUp is the
+// end-to-end companion for the confirmed-dead prune path: a non-terminal but
+// non-resumable (CREATED, no resume token) session with a session-only
+// executor_running row whose StopSession reports the runtime not-found and whose
+// local liveness is Dead must have its executor_running row removed after
+// cleanup — the durable job does not retry solely because the runtime was gone.
+func TestCleanupTaskResources_NonTerminalDeadLocalSessionGetsCleanedUp(t *testing.T) {
+	svc, _, repo := createTestService(t)
+
+	stopper := newRecordingTaskExecutionStopper()
+	// Mirror the not-found result executor.Stop now surfaces for a genuinely
+	// missing session (the runtime seam normalizes to runtimeapi.ErrNotFound).
+	stopper.stopSessionErr = fmt.Errorf("execution not found: %w: gone", runtimeapi.ErrNotFound)
+	svc.SetExecutionStopper(stopper)
+	svc.SetRowLivenessProber(stubRowLivenessProber{liveness: models.ProcessLivenessDead})
+	svc.setCleanupDoneForTestHook(make(chan struct{}, 1))
+
+	seedDeadLocalSessionOnly(t, repo, "ws-dl", "wf-dl", "task-dl", "sess-dead-local", "", models.TaskSessionStateCreated)
+
+	svc.CleanupTaskResources(context.Background(), "task-dl", false)
+	waitForCleanupDone(t, svc)
+
+	if _, err := repo.GetExecutorRunningBySessionID(context.Background(), "sess-dead-local"); err == nil {
+		t.Error("executor_running row must be removed for a confirmed-dead local non-resumable session")
+	}
+}
+
+// TestCleanupTaskResources_DeadLocalResumeSafeSessionRepairedNotDeleted is the
+// resume-safety end-to-end case: a confirmed-dead local row that still carries a
+// resume_token must be repaired in place (row preserved, token intact,
+// local_pid cleared) rather than deleted.
+func TestCleanupTaskResources_DeadLocalResumeSafeSessionRepairedNotDeleted(t *testing.T) {
+	svc, _, repo := createTestService(t)
+
+	stopper := newRecordingTaskExecutionStopper()
+	stopper.stopSessionErr = fmt.Errorf("execution not found: %w: gone", runtimeapi.ErrNotFound)
+	svc.SetExecutionStopper(stopper)
+	svc.SetRowLivenessProber(stubRowLivenessProber{liveness: models.ProcessLivenessDead})
+	svc.setCleanupDoneForTestHook(make(chan struct{}, 1))
+
+	// CREATED (non-resumable) state isolates the resume_token as the sole
+	// preservation driver.
+	seedDeadLocalSessionOnly(t, repo, "ws-rs", "wf-rs", "task-rs", "sess-resume-safe", "tok-keep", models.TaskSessionStateCreated)
+
+	svc.CleanupTaskResources(context.Background(), "task-rs", false)
+	waitForCleanupDone(t, svc)
+
+	row, err := repo.GetExecutorRunningBySessionID(context.Background(), "sess-resume-safe")
+	if err != nil {
+		t.Fatalf("resume-safe dead-local row must be preserved, not deleted: %v", err)
+	}
+	if row.ResumeToken != "tok-keep" {
+		t.Errorf("resume_token must survive repair; got %q", row.ResumeToken)
+	}
+	if row.Status != models.ExecutorRunningStatusStopped || row.LocalPID != 0 {
+		t.Errorf("dead row must be repaired to stopped with cleared local_pid; got status=%q local_pid=%d", row.Status, row.LocalPID)
+	}
+}
+
 func TestCleanupTaskResources_SkipsBorrowedInheritedWorktree(t *testing.T) {
 	svc, _, repo := createTestService(t)
 	ctx := context.Background()
diff --git a/apps/backend/internal/task/service/service_test.go b/apps/backend/internal/task/service/service_test.go
index 3a7b949ab2..3531166c7c 100644
--- a/apps/backend/internal/task/service/service_test.go
+++ b/apps/backend/internal/task/service/service_test.go
@@ -2555,6 +2555,7 @@ type recordingTaskExecutionStopper struct {
 	stopExecutionCh      chan stopExecutionCall
 	stopExecutionErr     error
 	stopExecutionErrByID map[string]error
+	stopSessionErr       error
 	claimExecutionFunc   func(sessionID, executionID string, force bool) bool
 }
 
@@ -2567,7 +2568,7 @@ func (s *recordingTaskExecutionStopper) StopTask(context.Context, string, string
 }
 
 func (s *recordingTaskExecutionStopper) StopSession(context.Context, string, string, bool) error {
-	return nil
+	return s.stopSessionErr
 }
 
 func (s *recordingTaskExecutionStopper) StopExecution(_ context.Context, executionID, reason string, force bool) error {
diff --git a/apps/backend/internal/task/service/service_workspace_sources_test.go b/apps/backend/internal/task/service/service_workspace_sources_test.go
index fa6af600cf..b91cbe2d98 100644
--- a/apps/backend/internal/task/service/service_workspace_sources_test.go
+++ b/apps/backend/internal/task/service/service_workspace_sources_test.go
@@ -24,7 +24,7 @@ func TestAttachWorkspaceSourcesDerivesLegacyPrimaryBranchForWorktreeProjection(t
 	}
 	primaryPath := t.TempDir()
 	seedBareGitDir(t, primaryPath, "ref: refs/heads/main\n")
-	if err := repo.CreateRepository(ctx, &models.Repository{ID: "repo-legacy-primary", WorkspaceID: "ws-legacy-primary", Name: "primary", LocalPath: primaryPath}); err != nil {
+	if err := repo.CreateRepository(ctx, &models.Repository{ID: "repo-legacy-primary", WorkspaceID: "ws-legacy-primary", Name: "primary", LocalPath: canonicalRepoTestPath(t, primaryPath)}); err != nil {
 		t.Fatal(err)
 	}
 	task, err := svc.CreateTask(ctx, &CreateTaskRequest{WorkspaceID: "ws-legacy-primary", WorkflowID: "wf-legacy-primary", WorkflowStepID: "step", Title: "Task", Repositories: []TaskRepositoryInput{{RepositoryID: "repo-legacy-primary"}}})
diff --git a/apps/backend/internal/worktree/directory_link_test.go b/apps/backend/internal/worktree/directory_link_test.go
index 47e3c7d1cd..136c3c64cd 100644
--- a/apps/backend/internal/worktree/directory_link_test.go
+++ b/apps/backend/internal/worktree/directory_link_test.go
@@ -6,8 +6,19 @@ import (
 	"testing"
 )
 
+// canonicalTempDir resolves symlinks in t.TempDir() so tests hand production
+// code a canonical owned control root (macOS /var -> /private/var).
+func canonicalTempDir(t *testing.T) string {
+	t.Helper()
+	d, err := filepath.EvalSymlinks(t.TempDir())
+	if err != nil {
+		t.Fatalf("EvalSymlinks(TempDir): %v", err)
+	}
+	return d
+}
+
 func TestCreateOwnedDirectoryLinkCreatesLiveLinkInsideOwnedRoot(t *testing.T) {
-	root := filepath.Join(t.TempDir(), "tasks", "task-1")
+	root := filepath.Join(canonicalTempDir(t), "tasks", "task-1")
 	target := filepath.Join(t.TempDir(), "source")
 	if err := os.MkdirAll(target, 0o755); err != nil {
 		t.Fatal(err)
@@ -72,7 +83,7 @@ func seedOwnedDirectoryLink(t *testing.T, root, name, target string) {
 // inspected entry is still on disk afterwards, since it may be a link the user
 // or the repository keeps on purpose.
 func TestIsSelfReferentialDirectoryLinkDetectsSelfLink(t *testing.T) {
-	root := t.TempDir()
+	root := canonicalTempDir(t)
 	seedOwnedDirectoryLink(t, root, "self", root)
 
 	selfLink, err := IsSelfReferentialDirectoryLink(root, "self")
@@ -85,7 +96,7 @@ func TestIsSelfReferentialDirectoryLinkDetectsSelfLink(t *testing.T) {
 }
 
 func TestIsSelfReferentialDirectoryLinkIgnoresForeignLink(t *testing.T) {
-	root, target := t.TempDir(), t.TempDir()
+	root, target := canonicalTempDir(t), t.TempDir()
 	if err := os.WriteFile(filepath.Join(target, "live.txt"), []byte("one"), 0o644); err != nil {
 		t.Fatal(err)
 	}
@@ -130,7 +141,7 @@ func TestIsSelfReferentialDirectoryLinkIgnoresMissingEntry(t *testing.T) {
 // call must be a no-op. A path-text comparison rejected Windows junctions here
 // because filepath.EvalSymlinks does not traverse them.
 func TestEnsureOwnedDirectoryLinkIsIdempotent(t *testing.T) {
-	root := filepath.Join(t.TempDir(), "tasks", "task-1")
+	root := filepath.Join(canonicalTempDir(t), "tasks", "task-1")
 	target := t.TempDir()
 	if err := os.WriteFile(filepath.Join(target, "live.txt"), []byte("one"), 0o644); err != nil {
 		t.Fatal(err)
@@ -156,7 +167,7 @@ func TestEnsureOwnedDirectoryLinkIsIdempotent(t *testing.T) {
 }
 
 func TestEnsureOwnedDirectoryLinkRejectsDifferentTarget(t *testing.T) {
-	root := filepath.Join(t.TempDir(), "tasks", "task-1")
+	root := filepath.Join(canonicalTempDir(t), "tasks", "task-1")
 	target, other := t.TempDir(), t.TempDir()
 	if _, _, err := EnsureOwnedDirectoryLink(root, "api", target); err != nil {
 		t.Fatalf("EnsureOwnedDirectoryLink: %v", err)
diff --git a/apps/backend/internal/worktree/manager_quarantine_cleanup_test.go b/apps/backend/internal/worktree/manager_quarantine_cleanup_test.go
index c30dd95351..89c91c933c 100644
--- a/apps/backend/internal/worktree/manager_quarantine_cleanup_test.go
+++ b/apps/backend/internal/worktree/manager_quarantine_cleanup_test.go
@@ -21,7 +21,7 @@ func TestPruneQuarantinedWorkspacePreservesOtherRecoverableRegistration(t *testi
 		t.Fatalf("NewManager: %v", err)
 	}
 
-	originalRoot := t.TempDir()
+	originalRoot := canonicalTempDir(t)
 	quarantineRoot := t.TempDir()
 	firstPath := filepath.Join(originalRoot, "task-1", "repo")
 	secondPath := filepath.Join(originalRoot, "task-2", "repo")
diff --git a/docs/plans/backend-regressions-office-disabled-cleanup/plan.md b/docs/plans/backend-regressions-office-disabled-cleanup/plan.md
new file mode 100644
index 0000000000..c2ee5283df
--- /dev/null
+++ b/docs/plans/backend-regressions-office-disabled-cleanup/plan.md
@@ -0,0 +1,131 @@
+---
+spec: docs/specs/platform/cron-office-disabled-safety.md
+created: 2026-08-03
+status: complete
+---
+
+# Implementation Plan: Three Backend Regressions
+
+Three independently reviewable backend regressions observed in
+`~/.kandev/logs/backend-logs.log`, repaired with TDD. Each task owns a disjoint
+package and is separately reviewable.
+
+## Related Specs
+
+- `docs/specs/platform/cron-office-disabled-safety.md` (Task 01, new repair spec)
+- `docs/specs/tasks/title-length-limit.md` (Task 02, amended)
+- `docs/specs/tasks/runtime-cleanup.md` (Task 03, amended)
+
+## Root Causes
+
+### 1. Office-disabled routines cron panic
+
+When Office is disabled, `services.OfficeSvcs` is nil so `officeRoutines` stays a
+nil `*office/routines.RoutineService` pointer
+(`backendapp/main.go:1280-1283`). `startCronScheduler`
+(`backendapp/cron.go:39`) passes that nil pointer straight into
+`schedulercron.NewRoutinesHandler(routineSvc, nil, log)`, which stores it in the
+`RoutineTicker` interface field. A typed-nil pointer inside an interface is a
+non-nil interface value, so `RoutinesHandler.Tick`'s `h.ticker == nil` guard
+(`scheduler/cron/routines.go:57-61`) is bypassed. `TickScheduledTriggers` then
+runs on a nil receiver and dereferences the service's repository, panicking every
+30 seconds. The loop's per-handler panic recovery re-arms each tick.
+
+### 2. GitHub review/issue titles exceed the 60-rune limit
+
+`buildReviewTaskRequest` (`orchestrator/event_handlers_github.go:451`) builds
+`fmt.Sprintf("PR #%d: %s", pr.Number, pr.Title)` with no length cap, and the
+issue watcher (`event_handlers_github.go:1368`) builds
+`fmt.Sprintf("Issue #%d: %s", ...)` the same way. Both feed `CreateReviewTask` /
+`CreateIssueTask` → `Service.CreateTask`, whose `validateTaskTitle(req.Title)`
+(`task/service/service_tasks.go:341`) rejects titles over 60 runes.
+`TruncateTaskTitle` is only applied to the auto-title derivation path
+(`service_tasks.go:212`), never to caller-supplied titles, so long PR/issue
+titles make the whole review/issue task fail to create.
+
+### 3. Missing-session runtime cleanup preserves stale rows
+
+`Executor.Stop` (`orchestrator/executor/executor_interaction.go:21-27`) maps
+every session-lookup error to `ErrExecutionNotFound`, and `StopExecution`
+(`:173-192`) wraps every stop error — including `lifecycle.ErrExecutionNotFound`
+— as `ErrExecutionNotFound` without letting callers distinguish "already gone"
+from "real failure". `handleMissingSessionOnStartup`
+(`orchestrator/service.go:1725-1748`) preserves the row whenever
+`StopAgentWithReason` returns any error, including a legitimate not-found for a
+dead process. In the durable worker, `executeTaskResourceCleanupJob`
+(`task/service/resource_cleanup_jobs.go:396,413-419`) counts every failed stop —
+not-found included — as a `failedStops` entry and returns an error, so the job
+re-enters `retry_wait` and exhausts its full retry budget (the documented
+eight-claim bound, whose eighth failed attempt becomes terminal `failed`) even
+though the runtime is already gone. Confirmed-dead local runtimes are never
+pruned and every cleanup for them burns the whole retry budget before failing.
+
+## Backend Changes
+
+- **Task 01 (cron):** In `backendapp/cron.go`, only assign the routines service
+  into a `schedulercron.RoutineTicker` variable when non-nil, so a genuinely nil
+  interface reaches `NewRoutinesHandler`. Optionally harden
+  `NewRoutinesHandler`/`Tick` to defend against a typed-nil concrete value.
+  Preserve normal forwarding when Office is enabled.
+- **Task 02 (titles):** Route the complete generated title through
+  `taskservice.TruncateTaskTitle` in `buildReviewTaskRequest` and the GitHub
+  issue task builder, before the request leaves the orchestrator.
+- **Task 03 (cleanup):** Add a runtime-aware "already stopped" classification so
+  a not-found stop for a confirmed-dead local row is a success, then thread it
+  through startup missing-session handling and the durable cleanup worker so such
+  rows are pruned/repaired under `RowMustBePreserved` and no longer counted as
+  failed stops. Preserve alive/unknown/remote rows and non-not-found errors.
+
+## Tests (RED before GREEN)
+
+- **Task 01:** Two complementary layers. Behavioral: `scheduler/cron/routines_test.go`
+  proves a handler built from a typed-nil `RoutineTicker` (the exact production
+  panic shape) takes the no-op branch on `Tick` without panicking. Static guard:
+  `backendapp/scheduler_wiring_test.go` asserts (via AST) that `startCronScheduler`
+  never passes the raw `routineSvc` pointer straight into `NewRoutinesHandler`,
+  so the nil-gating (`RoutineTicker` interface variable) cannot be dropped and
+  reintroduce the typed-nil interface. The backendapp check is intentionally
+  static — a runtime `startCronScheduler` test would require standing up the full
+  `*Repositories`/dispatcher graph for no additional behavioral coverage beyond
+  the handler test.
+- **Task 02:** `orchestrator/event_handlers_github_review_test.go` (and the issue
+  builder test) — ASCII and multibyte over-limit titles keep the `PR #`/`Issue #`
+  prefix, stay ≤60 runes, and end with `…`.
+- **Task 03:** `orchestrator/reconcile_restart_test.go` and
+  `task/service/service_tasks_stop_test.go` /
+  `task/service/resource_cleanup_jobs_test.go` — dead/alive/unknown-remote/
+  missing-session/terminal-session cases; confirmed-dead not-found prunes/repairs
+  and the cleanup job does not retry; alive/unknown preserved; non-not-found stays
+  retryable.
+
+## Implementation Waves And Parallel Candidates
+
+Task 02 and Task 03 both modify `internal/orchestrator` (Task 02 the GitHub
+title builders, Task 03 the stop-error classification), so they are not
+package-disjoint — but their files and symbols are disjoint, so they do not
+collide. Task 01 is fully isolated in `backendapp`+`scheduler/cron`. All three
+share no schema, migration, generated contract, lockfile, or package config.
+
+- Wave 1 (parallel-safe): Task 01, Task 02.
+- Wave 1 (sequential within itself): Task 03.
+
+`parallelism: sequential` remains the default per task; waves are a human aid,
+not authorization to delegate.
+
+- [x] [Task 01: Office-disabled routines cron no-op](task-01-office-disabled-routines-noop.md)
+- [x] [Task 02: Truncate generated review/issue task titles](task-02-truncate-generated-titles.md)
+- [x] [Task 03: Prune confirmed-dead missing-session runtime rows](task-03-confirmed-dead-runtime-cleanup.md)
+
+## Documentation Impact
+
+Durable specs are amended/added in this design package. No public CLI, config,
+API, or UI documentation changes are required.
+
+## Risks
+
+- Task 03 must classify only typed not-found sentinels for confirmed-dead local
+  rows; matching error strings or ignoring all not-found could hide real stop
+  failures or prune alive/remote rows. Judge "dead" with the existing
+  runtime-aware liveness probe, and gate deletion on `RowMustBePreserved`.
+- Task 01's typed-nil fix is small but easy to reintroduce; the regression test
+  must construct the typed-nil interface explicitly, not a plain `nil`.
diff --git a/docs/plans/backend-regressions-office-disabled-cleanup/task-01-office-disabled-routines-noop.md b/docs/plans/backend-regressions-office-disabled-cleanup/task-01-office-disabled-routines-noop.md
new file mode 100644
index 0000000000..ae7f73f3d3
--- /dev/null
+++ b/docs/plans/backend-regressions-office-disabled-cleanup/task-01-office-disabled-routines-noop.md
@@ -0,0 +1,75 @@
+---
+id: "01-office-disabled-routines-noop"
+title: "Office-disabled routines cron no-op"
+status: complete
+wave: 1
+depends_on: []
+plan: "plan.md"
+spec: "../../specs/platform/cron-office-disabled-safety.md"
+parallel-safe: true
+---
+
+# Task 01: Office-Disabled Routines Cron No-Op
+
+## Root Cause
+
+`backendapp/main.go:1280-1283` leaves `officeRoutines` a nil
+`*office/routines.RoutineService` pointer when Office is disabled.
+`startCronScheduler` (`backendapp/cron.go:39`) passes it into
+`schedulercron.NewRoutinesHandler`, storing a typed-nil pointer in the
+`RoutineTicker` interface field. `RoutinesHandler.Tick`'s `h.ticker == nil`
+guard (`scheduler/cron/routines.go:57-61`) is bypassed because a typed-nil
+pointer in an interface is a non-nil interface, so `TickScheduledTriggers` runs
+on a nil receiver and panics every 30 seconds.
+
+## Acceptance
+
+- With Office disabled, the shared cron loop ticks without a routines
+  nil-pointer panic and other handlers keep running.
+- A `RoutinesHandler` constructed from an absent routines service treats each
+  tick as a no-op returning success.
+- With Office enabled, each tick still forwards to
+  `RoutineService.TickScheduledTriggers` (behavior unchanged).
+
+## Regression Test (RED first)
+
+- In `scheduler/cron/routines_test.go`: build a handler whose ticker is a
+  typed-nil concrete `RoutineTicker` (i.e. a `(*fakeTicker)(nil)` assigned into
+  the interface, mirroring the production typed-nil) and assert `Tick` returns
+  nil without panic. Add/confirm a positive case that a real ticker is forwarded.
+- Add a `backendapp` test that `startCronScheduler` (or the routines-handler
+  wiring helper) with a nil routines service produces a handler that ticks safely.
+
+## Verification
+
+```bash
+cd apps/backend && go test -tags fts5 -run 'TestRoutinesHandler' ./internal/scheduler/cron
+cd apps/backend && go test -tags fts5 -run 'TestStartCronScheduler|TestCron' ./internal/backendapp
+```
+
+## Files likely touched
+
+- `apps/backend/internal/backendapp/cron.go`
+- `apps/backend/internal/backendapp/main.go` (only if wiring moves here)
+- `apps/backend/internal/scheduler/cron/routines.go` (optional hardening)
+- `apps/backend/internal/scheduler/cron/routines_test.go`
+- `apps/backend/internal/backendapp/*_test.go` (wiring regression)
+
+## Dependencies
+
+None.
+
+## Parallelism
+
+`sequential` within itself; `parallel-safe` against Tasks 02 and 03 (disjoint
+packages, no shared schema/contract/config).
+
+## Inputs
+
+- Repair spec: `docs/specs/platform/cron-office-disabled-safety.md`.
+- Confirmed 22 recurring panics in `~/.kandev/logs/backend-logs.log`.
+
+## Output contract
+
+Report the RED panic reproduction, the wiring change, files changed, exact
+verification result, residual risks, and update this task plus `plan.md` status.
diff --git a/docs/plans/backend-regressions-office-disabled-cleanup/task-02-truncate-generated-titles.md b/docs/plans/backend-regressions-office-disabled-cleanup/task-02-truncate-generated-titles.md
new file mode 100644
index 0000000000..363ccc1624
--- /dev/null
+++ b/docs/plans/backend-regressions-office-disabled-cleanup/task-02-truncate-generated-titles.md
@@ -0,0 +1,83 @@
+---
+id: "02-truncate-generated-titles"
+title: "Truncate generated review/issue task titles"
+status: complete
+wave: 1
+depends_on: []
+plan: "plan.md"
+spec: "../../specs/tasks/title-length-limit.md"
+parallel-safe: true
+---
+
+# Task 02: Truncate Generated Review/Issue Task Titles
+
+## Root Cause
+
+`buildReviewTaskRequest` (`orchestrator/event_handlers_github.go:451`) builds
+`fmt.Sprintf("PR #%d: %s", pr.Number, pr.Title)` and the issue watcher
+(`event_handlers_github.go:1368`) builds `fmt.Sprintf("Issue #%d: %s", ...)`,
+neither capped. Both feed `Service.CreateTask`, whose
+`validateTaskTitle(req.Title)` (`task/service/service_tasks.go:341`) rejects
+titles over 60 runes. `TruncateTaskTitle` is only applied to the auto-title
+derivation path, not caller-supplied titles, so long PR/issue titles drop the
+review/issue task entirely.
+
+## Acceptance
+
+- The complete generated review title and issue title are passed through
+  `taskservice.TruncateTaskTitle` before leaving the orchestrator.
+- Over-limit titles keep the `PR #<n>:` / `Issue #<n>:` prefix, are ≤60 runes,
+  and end with a single `…`. Multibyte titles are counted by code point.
+- Titles at or under 60 runes are unchanged.
+
+## Audit (in scope, do not broaden)
+
+`buildReviewTaskRequest` and the GitHub issue builder (`event_handlers_github.go`)
+are the two builders that feed `CreateTask` without truncation. Confirm; fix both.
+Adjacent builders are already safe and are OUT of scope unless a test shows
+otherwise: `event_handlers_automation.go` already calls `TruncateTaskTitle`
+(lines 314/321/324); `source_sentry.go` truncates via `truncateSentryTitle`;
+`office/routines/service.go:503` already truncates. `source_jira.go`,
+`source_linear.go`, `source_gitlab.go`, `source_azuredevops.go` build
+`IssueTaskRequest` titles — note them, but only fix if a regression test
+demonstrates they reach `CreateTask` without truncation.
+
+## Regression Test (RED first)
+
+- In `orchestrator/event_handlers_github_review_test.go`: table-driven
+  `buildReviewTaskRequest` cases — short ASCII (unchanged), long ASCII
+  (prefix kept, ≤60 runes, ends `…`), long multibyte (no split, ≤60 runes). Add
+  the equivalent for the issue builder.
+
+## Verification
+
+```bash
+cd apps/backend && go test -tags fts5 -run 'TestBuildReviewTaskRequest|TestBuildIssueTaskRequest|Title' ./internal/orchestrator
+```
+
+## Files likely touched
+
+- `apps/backend/internal/orchestrator/event_handlers_github.go`
+- `apps/backend/internal/orchestrator/event_handlers_github_review_test.go`
+- `apps/backend/internal/task/service/task_title.go` (read-only reference)
+
+## Dependencies
+
+None.
+
+## Parallelism
+
+`sequential` within itself; `parallel-safe` against Tasks 01 and 03.
+
+## Inputs
+
+- Amended spec: `docs/specs/tasks/title-length-limit.md` (watcher-title bullet
+  and scenarios).
+- Confirmed 5 "task title is too long" review-task failures in the logs
+  (PRs #12096, #12057, #12054).
+
+## Output contract
+
+Report the RED failures, the truncation change, the audit outcome for adjacent
+builders, files changed, exact verification result, residual risks, and update
+this task plus `plan.md` status.
diff --git a/docs/plans/backend-regressions-office-disabled-cleanup/task-03-confirmed-dead-runtime-cleanup.md b/docs/plans/backend-regressions-office-disabled-cleanup/task-03-confirmed-dead-runtime-cleanup.md
new file mode 100644
index 0000000000..3a5508f4eb
--- /dev/null
+++ b/docs/plans/backend-regressions-office-disabled-cleanup/task-03-confirmed-dead-runtime-cleanup.md
@@ -0,0 +1,101 @@
+---
+id: "03-confirmed-dead-runtime-cleanup"
+title: "Prune confirmed-dead missing-session runtime rows"
+status: complete
+wave: 1
+depends_on: []
+plan: "plan.md"
+spec: "../../specs/tasks/runtime-cleanup.md"
+parallel-safe: false
+---
+
+# Task 03: Prune Confirmed-Dead Missing-Session Runtime Rows
+
+## Root Cause
+
+- `Executor.Stop` (`orchestrator/executor/executor_interaction.go:21-27`) maps
+  every session-lookup error to `ErrExecutionNotFound`, and `StopExecution`
+  (`:173-192`) wraps every stop error — including `lifecycle.ErrExecutionNotFound`
+  — as `ErrExecutionNotFound`, so callers cannot tell "already gone" from a real
+  failure.
+- `handleMissingSessionOnStartup` (`orchestrator/service.go:1725-1748`) preserves
+  the row on any `StopAgentWithReason` error, including a legitimate not-found for
+  a dead process.
+- `executeTaskResourceCleanupJob`
+  (`task/service/resource_cleanup_jobs.go:396,413-419`) counts every failed stop
+  (not-found included) into `failedStops`, returns an error, and the job
+  re-enters `retry_wait` forever.
+
+## Acceptance
+
+- A not-found stop for a **confirmed-dead local** row (runtime-aware liveness ==
+  Dead) is recorded as a successful stop; the row is pruned or repaired under
+  `RowMustBePreserved` (token/worktree preserved when required).
+- Such a row is NOT counted as a `failedStops` entry, so the durable cleanup job
+  does not retry solely because the owned runtime is absent.
+- **Alive** and **Unknown/remote** (SSH/containerized/no local handle) rows are
+  preserved on a not-found stop and the outcome stays retryable.
+- Non-not-found session/task lookup or stop errors stay retryable; not every
+  session/execution not-found is blanket-ignored.
+- Runtime-specific persisted handles (e.g. `agent_execution_id`) are used to
+  decide the stop result where available.
+
+## Regression Test (RED first)
+
+- `orchestrator/reconcile_restart_test.go`: missing-session row that is
+  confirmed-dead-local + not-found stop → row pruned/repaired; alive → preserved;
+  unknown/remote (SSH) → preserved with handle+token; non-not-found stop error →
+  preserved retryable.
+- `task/service/service_tasks_stop_test.go` and
+  `task/service/resource_cleanup_jobs_test.go`: confirmed-dead not-found stop is
+  not a `failedStops` entry and the job completes (no retry); alive/unknown remain
+  failures/preserved; terminal-session case behaves per resume-safety.
+
+## Verification
+
+```bash
+cd apps/backend && go test -tags fts5 -run 'TestReconcile|MissingSession|StopExecution|Stop' ./internal/orchestrator ./internal/orchestrator/executor
+cd apps/backend && go test -tags fts5 -run 'TaskResourceCleanup|Stop|Cleanup' ./internal/task/service
+```
+
+## Files likely touched
+
+- `apps/backend/internal/orchestrator/executor/executor_interaction.go`
+- `apps/backend/internal/orchestrator/service.go`
+- `apps/backend/internal/orchestrator/reconcile_restart_test.go`
+- `apps/backend/internal/task/service/service_tasks.go`
+- `apps/backend/internal/task/service/service_tasks_stop_test.go`
+- `apps/backend/internal/task/service/resource_cleanup_jobs.go`
+- `apps/backend/internal/task/service/resource_cleanup_jobs_test.go`
+- `apps/backend/internal/task/models/resume_safety.go` (read-only reference)
+
+## Dependencies
+
+None on Tasks 01/02, but internally sequential: the error-classification change
+in the executor precedes the startup and worker consumers.
+
+## Parallelism
+
+`sequential`; spans `orchestrator`, `orchestrator/executor`, and `task/service`
+and must land as one reviewable change so callers and classification stay
+consistent. Not parallel-safe.
+
+## Inputs
+
+- Amended spec: `docs/specs/tasks/runtime-cleanup.md` (confirmed-dead
+  not-found-as-stopped bullets, failure modes, and scenarios).
+- Existing runtime-aware liveness: `lifecycle.RowProcessLiveness` /
+  `models.ProcessLiveness` and `RowMustBePreserved`
+  (`task/models/resume_safety.go`).
+- Existing sentinels: `lifecycle.ErrExecutionNotFound`,
+  `executor.ErrExecutionNotFound`, `runtimeapi.ErrNotFound`,
+  `models.ErrTaskSessionNotFound`, `models.ErrExecutorRunningNotFound`.
+- Confirmed "resumed task resource cleanup job failed: 1 runtime stop operations
+  failed" in the logs (job 7e3d58bd..., task 76cbddb5...).
+
+## Output contract
+
+Report the RED failures for each case (dead/alive/unknown-remote/missing-session/
+terminal), the classification and consumer changes, files changed, exact
+verification results, evidence the cleanup job no longer retries a confirmed-dead
+runtime, residual risks, and update this task plus `plan.md` status.
diff --git a/docs/specs/platform/cron-office-disabled-safety.md b/docs/specs/platform/cron-office-disabled-safety.md
new file mode 100644
index 0000000000..55fdd10627
--- /dev/null
+++ b/docs/specs/platform/cron-office-disabled-safety.md
@@ -0,0 +1,106 @@
+---
+status: draft
+created: 2026-08-03
+owner: cfl
+---
+
+# Shared Cron Loop Safety When Office Is Disabled
+
+## Why
+
+The shared cron loop (ADR-0004 Phase 5) drives every backend timer — heartbeat,
+budget, Office routines, and Office recovery — on a single goroutine. Office is
+an optional feature. When Office is disabled the routines collaborator does not
+exist, and the cron loop must keep running the other handlers instead of
+crashing. A crash here is severe because the loop's panic recovery re-arms every
+tick: the backend logs a nil-pointer panic every 30 seconds for the life of the
+process and never fires heartbeat or budget work.
+
+## What
+
+- The shared cron loop starts and keeps ticking whether or not Office is
+  enabled.
+- When the Office routines service is absent, the routines cron handler performs
+  no work and returns success on every tick. It does not panic, log an error, or
+  abort the loop.
+- When the Office routines service is present, the routines cron handler forwards
+  each tick to `RoutineService.TickScheduledTriggers` exactly as before. Enabling
+  Office does not change routine dispatch behavior.
+- The remaining cron handlers (heartbeat, budget, Office recovery) run
+  independently of whether the routines handler is a no-op.
+- Wiring a nil collaborator into any cron handler is safe: a genuinely absent
+  collaborator produces a no-op handler, never a handler that dereferences a nil
+  value during `Tick`.
+
+## Data Model
+
+No data model change. The behavior concerns in-process wiring of the cron loop
+handlers only.
+
+## API Surface
+
+No user-facing HTTP or WebSocket surface. The affected contract is the internal
+cron handler seam:
+
+```go
+// RoutineTicker is the surface RoutinesHandler needs from the office
+// routines service.
+type RoutineTicker interface {
+    TickScheduledTriggers(ctx context.Context, now time.Time) error
+}
+
+func NewRoutinesHandler(ticker RoutineTicker, now func() time.Time, log *logger.Logger) *RoutinesHandler
+```
+
+`RoutinesHandler.Tick` treats a nil ticker as a no-op. The safety guarantee is
+that this nil check is reached whenever no routines service is configured,
+regardless of how the absence is expressed by the caller.
+
+## Failure Modes
+
+- **Typed-nil collaborator (the regression).** A concrete nil pointer
+  (`(*office/routines.RoutineService)(nil)`) assigned into the `RoutineTicker`
+  interface produces a non-nil interface value. `RoutinesHandler.Tick`'s
+  `h.ticker == nil` guard is then bypassed, `TickScheduledTriggers` runs on a nil
+  receiver, dereferences the service's repository, and panics. The cron loop's
+  per-handler panic recovery converts this into a recurring error every tick.
+  Desired behavior: the handler must observe a genuinely nil interface when no
+  service exists, so the no-op branch is taken.
+- **Office enabled but routines service still nil.** Should never happen in
+  practice, but the handler must still no-op rather than panic.
+- **Routines service returns an error while Office is enabled.** Unchanged: the
+  error propagates from `Tick` to the loop, which logs it without aborting other
+  handlers.
+
+## Persistence Guarantees
+
+None. This behavior is process-local wiring and has no persisted state.
+
+## Scenarios
+
+- **GIVEN** the backend starts with Office disabled, **WHEN** the shared cron
+  loop ticks, **THEN** the routines handler performs no work, returns success,
+  does not panic, and the heartbeat, budget, and Office-recovery handlers keep
+  running.
+- **GIVEN** the backend starts with Office disabled, **WHEN** the cron loop runs
+  for multiple ticks, **THEN** no nil-pointer panic is logged for the routines
+  handler on any tick.
+- **GIVEN** the backend starts with Office enabled and a real routines service,
+  **WHEN** the cron loop ticks, **THEN** the routines handler forwards each tick
+  to `RoutineService.TickScheduledTriggers` and normal routine dispatch is
+  unchanged.
+- **GIVEN** a routines cron handler is constructed with a nil routines
+  collaborator by any wiring path, **WHEN** it ticks, **THEN** it returns success
+  without dereferencing the collaborator.
+
+## Out of Scope
+
+- Changing routine dispatch, concurrency policy, fingerprinting, or cron
+  expression evaluation inside the Office routines service.
+- Changing heartbeat, budget, or Office-recovery handler behavior.
+- Adding a user-facing surface for cron health.
+- Making the cron tick interval configurable.
+
+## Implementation Plan
+
+See [the implementation plan](../../plans/backend-regressions-office-disabled-cleanup/plan.md).
diff --git a/docs/specs/tasks/runtime-cleanup.md b/docs/specs/tasks/runtime-cleanup.md
index e0f71636c2..106c3e4b00 100644
--- a/docs/specs/tasks/runtime-cleanup.md
+++ b/docs/specs/tasks/runtime-cleanup.md
@@ -55,6 +55,28 @@ worktrees, or executor rows behind and the machine slowly runs out of memory.
 - A cleanup operation treats a classifiable missing owned resource as already
   complete. This includes a missing worktree and a missing `TaskEnvironment`
   row captured by the durable cleanup snapshot.
+- Stopping a runtime that is already gone is a successful, idempotent stop, not a
+  failed stop. When a stop operation is asked to stop an execution or session
+  that no longer exists, and the row it owns is a confirmed-dead local runtime,
+  the cleanup treats the runtime as already stopped so the runtime row can be
+  pruned or repaired under the resume-safety invariant and the durable cleanup
+  job does not retry solely because the owned runtime is absent.
+- "Confirmed dead" is judged in a runtime-aware way. A row is confirmed dead only
+  when it is a local runtime whose local liveness handle refers to a process that
+  no longer exists on this host. An alive local runtime, or a runtime whose
+  liveness is Unknown (remote SSH, containerized, or a local row with no liveness
+  handle), is never treated as dead on the basis of a not-found stop result; its
+  row is preserved and the outcome remains retryable.
+- Missing-runtime handling never blanket-ignores every session-level or
+  execution-level not-found error. Only a not-found result for a runtime whose row
+  is confirmed dead is reclassified as a successful stop. A not-found result for
+  an alive or unknown/remote row, or a session/task lookup error that is not a
+  typed not-found sentinel, remains a preserved, retryable outcome so a transient
+  store error is never mistaken for an absent runtime.
+- Where a runtime-specific persisted stop handle exists (for example
+  `agent_execution_id`, or a remote/container handle), missing-runtime handling
+  uses it to decide the stop result rather than inferring absence from a generic
+  error.
 - Archive, delete, cascade, workspace-delete, and quick-chat expiration persist a
   cleanup intent and resource snapshot before mutating or deleting task state.
   Cleanup is performed by a durable worker rather than a detached goroutine.
@@ -174,6 +196,18 @@ The durable cleanup job wraps that resource lifecycle:
 - If a runtime row points at a missing in-memory execution, cleanup attempts the
   runtime-specific persisted handle when available. If no handle can be used, the
   row is preserved with a warning instead of being silently dropped.
+- If a stop operation reports the execution or session is not found and the owned
+  row is a confirmed-dead local runtime, cleanup records the stop as successful,
+  prunes or repairs the row under the resume-safety invariant, proceeds with any
+  now-safe shared-environment/worktree teardown, and does not count the row as a
+  failed stop. The durable cleanup job therefore does not re-enter `retry_wait`
+  solely because that owned runtime was confirmed absent.
+- If a stop operation reports not found but the owned row is alive, or its
+  liveness is Unknown (remote/containerized/no local handle), cleanup preserves
+  the row and treats the outcome as retryable rather than pruning it.
+- If a session or task lookup during stop fails with an error that is not a typed
+  not-found sentinel, cleanup treats it as a retryable failure and preserves the
+  row; it does not reinterpret the error as an absent runtime.
 - If worktree or task environment cleanup fails after runtime shutdown is
   confirmed, the runtime tracking row can still be removed because it no longer
   identifies a live process. The resource cleanup error is logged and handled by
@@ -241,6 +275,29 @@ The durable cleanup job wraps that resource lifecycle:
 - **GIVEN** the backend restarts with an `executors_running` row for an archived
   task, **WHEN** startup reconciliation runs, **THEN** it attempts cleanup for the
   row instead of treating the archived task as active.
+- **GIVEN** an `executors_running` row whose task session is missing and whose
+  local liveness handle refers to a dead host process, **WHEN** startup
+  reconciliation stops it and the stop reports the execution is not found, **THEN**
+  the row is pruned or repaired under the resume-safety invariant instead of being
+  preserved indefinitely.
+- **GIVEN** a resumed durable cleanup job whose only remaining runtime target is a
+  confirmed-dead local runtime, **WHEN** the cleanup worker stops it and the stop
+  reports not found, **THEN** the job records a successful stop, completes owned
+  resource teardown, and does not re-enter `retry_wait` because of that runtime.
+- **GIVEN** an `executors_running` row that is still alive on this host, **WHEN**
+  a stop reports not found for it, **THEN** the row is preserved and the outcome is
+  treated as retryable rather than pruned.
+- **GIVEN** an `executors_running` row for a remote (SSH) or containerized runtime
+  whose local liveness is Unknown, **WHEN** a stop reports not found, **THEN** the
+  row is preserved with its remote handle and resume token intact and is not
+  pruned on the basis of a host-local not-found.
+- **GIVEN** a session lookup during a stop fails with a non-not-found store error,
+  **WHEN** cleanup evaluates the result, **THEN** it preserves the row and retries
+  rather than treating the runtime as absent.
+- **GIVEN** a confirmed-dead local row that still carries a resume token, **WHEN**
+  a not-found stop is reclassified as successful, **THEN** the row is repaired in
+  place (token and worktree preserved) rather than deleted, per
+  `RowMustBePreserved`.
 - **GIVEN** agentctl is stopped while an ACP child process ignores stdin EOF,
   **WHEN** the stop timeout expires, **THEN** the ACP process group is killed and
   no ACP child is reparented to PID 1.
diff --git a/docs/specs/tasks/title-length-limit.md b/docs/specs/tasks/title-length-limit.md
index 96f5feff0d..f12d1e42b6 100644
--- a/docs/specs/tasks/title-length-limit.md
+++ b/docs/specs/tasks/title-length-limit.md
@@ -17,6 +17,8 @@ Long task titles crowd navigation and task chrome, especially when a remote pull
 - When a remote pull request, merge request, or issue supplies a title longer than 60 characters, the task dialog uses the first 59 characters followed by `…`. The full remote title remains available in the generated task description or linked remote item; only the task title is shortened.
 - The `create_task_kandev` MCP tool advertises and enforces the 60-character limit and asks agents to use a concise, few-word title.
 - Backend task creation and title updates reject titles longer than 60 characters regardless of whether the caller uses HTTP, WebSocket, MCP, Office, automation, or another service adapter.
+- The GitHub review-PR and GitHub issue watchers, which construct `PR #<n>: <title>` and `Issue #<n>: <title>` respectively, shorten the complete generated title (including the `PR #<n>:` or `Issue #<n>:` prefix) to at most 60 characters before it reaches task creation. A title that is shortened ends with a single `…` and never exceeds 60 runes counted by Unicode code point, so multibyte titles are not split mid-character. Because backend task creation rejects overlong titles, a watcher that skips this shortening drops the review/issue task entirely instead of creating a shortened one — this is the concrete regression this limit fixes for the GitHub paths.
+- Every other backend watcher that turns a remote item into a task through the shared watcher-dispatch pipeline — Linear (`[<identifier>] <title>`), Jira (`[<key>] <summary>`), GitLab merge-request and issue (`[<path>!<n>]`/`[<path>#<n>] <title>`), and Azure DevOps work-item and pull-request (`[<project>#<n>] <title>`) — has its complete generated title shortened to at most 60 runes (ending with a single `…` when shortened, counted by Unicode code point) before it reaches task creation. The dispatch coordinator applies this once at the shared seam after each source builds its request, so a source cannot skip it and every current and future watcher source inherits the guarantee automatically. The automation-trigger path likewise routes its generated title through the shared truncation helper. New watcher paths that auto-generate a title from a remote item are covered by the coordinator with no per-source work.
 - Existing stored titles longer than 60 characters remain readable and are not rewritten. Updates that omit `title` continue to work; any submitted replacement title must satisfy the new limit.
 
 ## API surface
@@ -41,6 +43,9 @@ Long task titles crowd navigation and task chrome, especially when a remote pull
 - **GIVEN** an MCP caller supplies a title longer than 60 characters, **WHEN** it calls `create_task_kandev`, **THEN** the call returns a validation error and creates no task.
 - **GIVEN** an HTTP or WebSocket caller supplies an overlong title for task creation or rename, **WHEN** the request is handled, **THEN** it returns the channel's validation response and leaves stored data unchanged.
 - **GIVEN** an existing task with a legacy title longer than 60 characters, **WHEN** a caller updates another task field without submitting `title`, **THEN** the existing title remains unchanged.
+- **GIVEN** a GitHub review watcher observes a pull request whose `PR #<n>: <title>` string exceeds 60 characters, **WHEN** the review task is created, **THEN** the generated title is shortened to at most 60 runes ending with `…`, the `PR #<n>:` prefix is retained, and the review task is created rather than dropped.
+- **GIVEN** a GitHub issue watcher observes an issue whose `Issue #<n>: <title>` string exceeds 60 characters, **WHEN** the issue task is created, **THEN** the generated title is shortened to at most 60 runes ending with `…`, the `Issue #<n>:` prefix is retained, and the issue task is created rather than dropped.
+- **GIVEN** a watcher-generated title contains multibyte characters near the 60-rune boundary, **WHEN** it is shortened, **THEN** the result is counted by Unicode code point and no character is split.
 
 ## Out of scope