diff --git a/packages/ui/src/components/sections/openchamber/WorktreeSectionContent.tsx b/packages/ui/src/components/sections/openchamber/WorktreeSectionContent.tsx
index 2edcf0f8..1fee25b1 100644
--- a/packages/ui/src/components/sections/openchamber/WorktreeSectionContent.tsx
+++ b/packages/ui/src/components/sections/openchamber/WorktreeSectionContent.tsx
@@ -4,10 +4,12 @@ import { Checkbox } from '@/components/ui/checkbox';
 import { Input } from '@/components/ui/input';
 import { Tooltip, TooltipContent, TooltipTrigger } from '@/components/ui/tooltip';
 import { Icon } from "@/components/icon/Icon";
+import type { Session } from '@opencode-ai/sdk/v2';
 import { useProjectsStore } from '@/stores/useProjectsStore';
 import { useSessionUIStore } from '@/sync/session-ui-store';
 import { useSessions } from '@/sync/sync-context';
 import { useDirectoryStore } from '@/stores/useDirectoryStore';
+import { useGlobalSessionsStore } from '@/stores/useGlobalSessionsStore';
 import { useDeviceInfo } from '@/lib/device';
 import { checkIsGitRepository } from '@/lib/gitApi';
 import {
@@ -228,10 +230,17 @@ export const WorktreeSectionContent: React.FC<WorktreeSectionContentProps> = ({
     // Build a set of session IDs that are directly linked
     const directSessionIds = new Set(directSessions.map((s) => s.id));
 
-    // Find all subsessions recursively
-    const findSubsessions = (parentIds: Set<string>): typeof sessions => {
-      const subsessions = sessions.filter((session) => {
-        const parentID = (session as { parentID?: string | null }).parentID;
+    // Search subsessions across all directories, not just the current sync
+    // context, so subagent sessions created in other worktrees/project roots
+    // are still included in the delete list.
+    const allKnownSessions = [
+      ...useGlobalSessionsStore.getState().activeSessions,
+      ...useGlobalSessionsStore.getState().archivedSessions,
+    ];
+
+    const findSubsessions = (parentIds: Set<string>): Session[] => {
+      const subsessions = allKnownSessions.filter((session) => {
+        const parentID = (session as Session & { parentID?: string | null }).parentID;
         return parentID && parentIds.has(parentID);
       });
       if (subsessions.length === 0) {
diff --git a/packages/ui/src/components/session/sidebar/SessionGroupSection.tsx b/packages/ui/src/components/session/sidebar/SessionGroupSection.tsx
index 0768a099..1e854bca 100644
--- a/packages/ui/src/components/session/sidebar/SessionGroupSection.tsx
+++ b/packages/ui/src/components/session/sidebar/SessionGroupSection.tsx
@@ -675,12 +675,13 @@ function SessionGroupSectionBase(props: Props): React.ReactNode {
     return collected;
   }, []);
 
-  // The "delete all in group" handler closes over the full list of
-  // sessions in this group. Memoize so the recursive flatten only runs
-  // when the underlying source group nodes change, not on every render.
+  // Flat list of all sessions in this group (including nested children).
+  // Used by both the "delete all archived" button and the "delete worktree"
+  // button. Memoize so the recursive flatten only runs when the underlying
+  // source group nodes change, not on every render.
   const allGroupSessions = React.useMemo(
-    () => (group.isArchivedBucket ? collectGroupSessions(sourceGroupNodes) : []),
-    [collectGroupSessions, sourceGroupNodes, group.isArchivedBucket],
+    () => collectGroupSessions(sourceGroupNodes),
+    [collectGroupSessions, sourceGroupNodes],
   );
 
   // Precompute the per-folder "delete all sessions in folder" list once
diff --git a/packages/ui/src/components/session/sidebar/hooks/useSessionActions.ts b/packages/ui/src/components/session/sidebar/hooks/useSessionActions.ts
index e7447fae..7338be53 100644
--- a/packages/ui/src/components/session/sidebar/hooks/useSessionActions.ts
+++ b/packages/ui/src/components/session/sidebar/hooks/useSessionActions.ts
@@ -217,13 +217,12 @@ export const useSessionActions = (args: Args) => {
 
       const ids = [session.id, ...descendantIds];
       if (shouldHardDelete) {
-        // The server cascade-deletes all descendant sessions when the parent
-        // is removed. Only send the root session delete request; sending
-        // individual requests for each descendant would hit 404 (already
-        // deleted by cascade) and trigger rollback that restores them.
-        const success = await args.deleteSession(session.id);
-        if (success) {
-          const totalDeleted = descendantIds.length + 1;
+        // Delete root + all descendants individually. If the server
+        // cascade-deletes some children before we get to them, 404 is
+        // treated as success by deleteSession and no rollback occurs.
+        const { deletedIds, failedIds } = await args.deleteSessions(ids);
+        if (failedIds.length === 0) {
+          const totalDeleted = deletedIds.length;
           toast.success(totalDeleted === 1
             ? t('sessions.sidebar.bulkActions.deletedSingle', { count: totalDeleted })
             : t('sessions.sidebar.bulkActions.deletedPlural', { count: totalDeleted }));
diff --git a/packages/ui/src/sync/session-actions.ts b/packages/ui/src/sync/session-actions.ts
index 05a9092c..8d4fe796 100644
--- a/packages/ui/src/sync/session-actions.ts
+++ b/packages/ui/src/sync/session-actions.ts
@@ -466,6 +466,10 @@ function restoreSessionListSnapshots(snapshots: SessionListSnapshot[]): void {
   }
 }
 
+function cleanupSessionWorktreeMetadata(sessionId: string): void {
+  useSessionUIStore.getState().setWorktreeMetadata(sessionId, null)
+}
+
 // eslint-disable-next-line @typescript-eslint/no-unused-vars
 export async function deleteSession(sessionId: string, _options?: Record<string, unknown>): Promise<boolean> {
   const sessionDirectory = getSessionDirectory(sessionId)
@@ -484,6 +488,7 @@ export async function deleteSession(sessionId: string, _options?: Record<string,
       throw new Error("session.delete failed: server did not confirm deletion")
     }
     useGlobalSessionsStore.getState().removeSessions([sessionId])
+    cleanupSessionWorktreeMetadata(sessionId)
     return true
   } catch (error) {
     console.error("[session-actions] deleteSession failed", error)
@@ -491,6 +496,7 @@ export async function deleteSession(sessionId: string, _options?: Record<string,
     // Subsequent delete attempts for those children return 404; treat as
     // success since the session was already deleted by the cascade.
     if ((error as { status?: number })?.status === 404) {
+      cleanupSessionWorktreeMetadata(sessionId)
       return true
     }
     restoreSessionListSnapshots(snapshots)
@@ -514,10 +520,12 @@ export async function deleteSessionInDirectory(sessionId: string, directory: str
       throw new Error("session.delete failed: server did not confirm deletion")
     }
     useGlobalSessionsStore.getState().removeSessions([sessionId])
+    cleanupSessionWorktreeMetadata(sessionId)
     return true
   } catch (error) {
     console.error("[session-actions] deleteSessionInDirectory failed", error)
     if ((error as { status?: number })?.status === 404) {
+      cleanupSessionWorktreeMetadata(sessionId)
       return true
     }
     restoreSessionListSnapshots(snapshots)