diff --git a/frontend/src/app/DocumentsRoute.tsx b/frontend/src/app/DocumentsRoute.tsx
index 694e91f..42af412 100644
--- a/frontend/src/app/DocumentsRoute.tsx
+++ b/frontend/src/app/DocumentsRoute.tsx
@@ -40,7 +40,7 @@ const DocumentsInner: React.FC<{
 
   const handleOpenSidepanel = useCallback((docId: string) => {
     if (openDetailPanel) {
-      openDetailPanel({ documentIds: [docId] });
+      openDetailPanel(docId);
     }
   }, [openDetailPanel]);
 
diff --git a/frontend/src/app/useDetailPanel.ts b/frontend/src/app/useDetailPanel.ts
index af7c594..3df14c1 100644
--- a/frontend/src/app/useDetailPanel.ts
+++ b/frontend/src/app/useDetailPanel.ts
@@ -1,97 +1,46 @@
-import { useCallback, useEffect, useRef, useState } from 'react';
+import { useCallback, useEffect, useState } from 'react';
+import type { Identifier } from '../types/identifiers';
 
 interface DetailDocument {
-  id?: string;
+  id?: Identifier;
   [key: string]: unknown;
 }
 
 interface UseDetailPanelOptions {
-  documentLookup: Map<string, DetailDocument>;
-  orderedSelectedDocuments: DetailDocument[];
-}
-
-interface OpenDetailPanelArgs {
-  documentId?: string;
-  document?: DetailDocument | null;
-  documentIds?: Array<string>;
-  documents?: DetailDocument[];
+  documentLookup: Map<Identifier, DetailDocument>;
 }
 
 export const useDetailPanel = ({
   documentLookup,
-  orderedSelectedDocuments,
 }: UseDetailPanelOptions) => {
-  const [detailPanelOpen, setDetailPanelOpen] = useState(false);
-  const [detailPanelDocId, setDetailPanelDocId] = useState<string | null>(null);
+  const [detailPanelDocId, setDetailPanelDocId] = useState<Identifier | null>(null);
   const [detailPanelDocument, setDetailPanelDocument] = useState<DetailDocument | null>(null);
-  const latestOrderedDocsRef = useRef<DetailDocument[]>([]);
 
-  useEffect(() => {
-    latestOrderedDocsRef.current = orderedSelectedDocuments;
-    if (detailPanelOpen && orderedSelectedDocuments.length) {
-      const nextDoc = orderedSelectedDocuments[orderedSelectedDocuments.length - 1];
-      if (nextDoc?.id) {
-        setDetailPanelDocId(nextDoc.id);
-        setDetailPanelDocument(nextDoc);
-      }
-    }
-  }, [orderedSelectedDocuments, detailPanelOpen]);
+  const detailPanelOpen = detailPanelDocId !== null;
 
   useEffect(() => {
     if (!detailPanelDocId) {
-      if (!detailPanelOpen) {
-        setDetailPanelDocument(null);
-      }
+      setDetailPanelDocument(null);
       return;
     }
-    const resolved = documentLookup.get(detailPanelDocId);
-    if (resolved && resolved !== detailPanelDocument) {
+    const resolved = documentLookup.get(detailPanelDocId) ?? null;
+    if (resolved !== detailPanelDocument) {
       setDetailPanelDocument(resolved);
     }
-  }, [detailPanelDocId, documentLookup, detailPanelDocument, detailPanelOpen]);
+  }, [detailPanelDocId, documentLookup, detailPanelDocument]);
 
   const openDetailPanel = useCallback(
-    ({ documentId, document, documentIds, documents }: OpenDetailPanelArgs = {}) => {
-      let targetDoc = document || null;
-      let targetId = documentId ?? document?.id ?? null;
-
-      if (!targetDoc && Array.isArray(documents) && documents.length) {
-        targetDoc = documents[documents.length - 1];
-        targetId = targetDoc?.id ?? targetId;
-      }
-
-      if (!targetDoc && Array.isArray(documentIds) && documentIds.length) {
-        targetId = documentIds[documentIds.length - 1];
-      }
-
-      if (!targetDoc && targetId != null) {
-        targetDoc = documentLookup.get(String(targetId)) || null;
-      }
-
-      if (!targetDoc) {
-        const fallbackDocs = latestOrderedDocsRef.current;
-        const fallbackDoc = Array.isArray(fallbackDocs) && fallbackDocs.length
-          ? fallbackDocs[fallbackDocs.length - 1]
-          : null;
-        if (fallbackDoc) {
-          targetDoc = fallbackDoc;
-          targetId = fallbackDoc.id;
-        }
-      }
-
-      if (!targetDoc && targetId == null) {
+    (documentId: Identifier) => {
+      if (!documentId) {
         return;
       }
-
-      setDetailPanelDocId(targetDoc?.id ?? targetId ?? null);
-      setDetailPanelDocument(targetDoc || null);
-      setDetailPanelOpen(Boolean(targetDoc || targetId));
+      setDetailPanelDocId(documentId);
     },
-    [documentLookup],
+    [],
   );
 
   const closeDetailPanel = useCallback(() => {
-    setDetailPanelOpen(false);
+    setDetailPanelDocId(null);
   }, []);
 
   return {
@@ -99,6 +48,5 @@ export const useDetailPanel = ({
     detailPanelDocument,
     openDetailPanel,
     closeDetailPanel,
-    setDetailPanelOpen,
   };
 };
diff --git a/frontend/src/app/useDocumentsShell.ts b/frontend/src/app/useDocumentsShell.ts
index d1b0fe0..509f1a8 100644
--- a/frontend/src/app/useDocumentsShell.ts
+++ b/frontend/src/app/useDocumentsShell.ts
@@ -7,7 +7,7 @@ import type { UseWorkspaceSurfaceArgs } from './useWorkspaceSurface';
 import type { Identifier } from '../types/identifiers';
 
 type WorkspaceSurfaceConfig = Omit<UseWorkspaceSurfaceArgs, 'sidebarHidden' | 'onExpandSidebar'> & {
-  openDetailPanel?: (args: { documentIds?: Identifier[] }) => void;
+  openDetailPanel?: (documentId: Identifier) => void;
   closeDetailPanel?: () => void;
 };
 
diff --git a/frontend/src/detail/useDetailWorkspace.ts b/frontend/src/detail/useDetailWorkspace.ts
index 438cdb0..5df41d9 100644
--- a/frontend/src/detail/useDetailWorkspace.ts
+++ b/frontend/src/detail/useDetailWorkspace.ts
@@ -3,7 +3,6 @@ import type { MutableRefObject } from 'react';
 import { resolveDocumentAssetUrl } from '../asset_manager';
 import { useDetailPanel } from '../app/useDetailPanel';
 import { DEFAULT_FOLDER_NAME } from '../app/workspaceUtils';
-import { getEntryId, isDocumentEntry } from '../app/entryKey';
 import type { DocumentInfoPanelProps } from '../documents/DocumentInfoPanel';
 import type { EnsureAssetUrl, GetDocumentAsset } from '../utils/ocr';
 import type { Identifier } from '../types/identifiers';
@@ -17,12 +16,10 @@ interface FolderNode {
 
 interface UseDetailWorkspaceArgs {
   documents: Document[];
-  selectionOrder: string[];
-  selectedDocumentIds: Identifier[];
   documentLookup: Map<Identifier, Document>;
   folderNodes: Map<Identifier | 'root', FolderNode>;
   ensureFolderData: (folderId: Identifier | 'root', options?: { force?: boolean; includeDocuments?: boolean }) => Promise<void>;
-  detailPanelControlRef: MutableRefObject<{ open?: (args?: { documentIds?: Identifier[] }) => void; close?: () => void } | null>;
+  detailPanelControlRef: MutableRefObject<{ open?: (documentId: Identifier) => void; close?: () => void } | null>;
   detailFolderFetchRef: MutableRefObject<Set<Identifier | 'root'>>;
   previewDocumentId?: Identifier | null;
   activePreviewId?: Identifier | null;
@@ -56,8 +53,6 @@ interface UseDetailWorkspaceResult {
 
 const useDetailWorkspace = ({
   documents,
-  selectionOrder,
-  selectedDocumentIds,
   documentLookup,
   folderNodes,
   ensureFolderData,
@@ -79,37 +74,6 @@ const useDetailWorkspace = ({
   tags,
   tagLookupById,
 }: UseDetailWorkspaceArgs): UseDetailWorkspaceResult => {
-  const orderedSelectedDocuments = useMemo(() => {
-    const ordered = [];
-    const seen = new Set();
-
-    const pushDoc = (doc) => {
-      if (doc?.id && !seen.has(doc.id)) {
-        ordered.push(doc);
-        seen.add(doc.id);
-      }
-    };
-
-    selectionOrder.forEach((key) => {
-      if (!isDocumentEntry(key)) {
-        return;
-      }
-      const docId = getEntryId(key);
-      const doc = documentLookup.get(docId) || null;
-      pushDoc(doc);
-    });
-
-    selectedDocumentIds.forEach((docId) => {
-      if (seen.has(docId)) {
-        return;
-      }
-      const doc = documentLookup.get(docId) || null;
-      pushDoc(doc);
-    });
-
-    return ordered;
-  }, [selectionOrder, documentLookup, selectedDocumentIds]);
-
   const {
     detailPanelOpen,
     detailPanelDocument,
@@ -117,7 +81,6 @@ const useDetailWorkspace = ({
     closeDetailPanel,
   } = useDetailPanel({
     documentLookup,
-    orderedSelectedDocuments,
   });
 
   useEffect(() => {
@@ -127,52 +90,46 @@ const useDetailWorkspace = ({
     };
   }, [detailPanelControlRef, openDetailPanel, closeDetailPanel]);
 
+  // Prefetch folder ancestors for breadcrumb display
   useEffect(() => {
-    if (!orderedSelectedDocuments.length) {
+    const folderId = detailPanelDocument?.folder_id;
+    if (!folderId) {
       return;
     }
 
     const visited = new Set();
+    let currentId = folderId;
+    let guard = 0;
 
-    orderedSelectedDocuments.forEach((doc) => {
-      const folderId = doc?.folder_id;
-      if (!folderId) {
-        return;
+    while (currentId && currentId !== 'root' && guard < 32) {
+      guard += 1;
+      if (visited.has(currentId)) {
+        break;
+      }
+      visited.add(currentId);
+
+      const node = folderNodes.get(currentId);
+      if (!node) {
+        if (!detailFolderFetchRef.current.has(currentId)) {
+          detailFolderFetchRef.current.add(currentId);
+          ensureFolderData(currentId, { force: false, includeDocuments: false })
+            .catch((error) => {
+              console.warn('Failed to preload folder metadata for detail path', currentId, error);
+            })
+            .finally(() => {
+              detailFolderFetchRef.current.delete(currentId);
+            });
+        }
+        break;
       }
 
-      let currentId = folderId;
-      let guard = 0;
-
-      while (currentId && currentId !== 'root' && guard < 32) {
-        guard += 1;
-        if (visited.has(currentId)) {
-          break;
-        }
-        visited.add(currentId);
-
-        const node = folderNodes.get(currentId);
-        if (!node) {
-          if (!detailFolderFetchRef.current.has(currentId)) {
-            detailFolderFetchRef.current.add(currentId);
-            ensureFolderData(currentId, { force: false, includeDocuments: false })
-              .catch((error) => {
-                console.warn('Failed to preload folder metadata for detail path', currentId, error);
-              })
-              .finally(() => {
-                detailFolderFetchRef.current.delete(currentId);
-              });
-          }
-          break;
-        }
-
-        const parentId = node.parentId ?? 'root';
-        if (!parentId || parentId === 'root') {
-          break;
-        }
-        currentId = parentId;
+      const parentId = node.parentId ?? 'root';
+      if (!parentId || parentId === 'root') {
+        break;
       }
-    });
-  }, [orderedSelectedDocuments, folderNodes, ensureFolderData, detailFolderFetchRef]);
+      currentId = parentId;
+    }
+  }, [detailPanelDocument, folderNodes, ensureFolderData, detailFolderFetchRef]);
 
   const resolveFolderPath = useCallback(
     (folderId) => {
@@ -240,11 +197,11 @@ const useDetailWorkspace = ({
   );
 
   const inspectDocument = useCallback(
-    (documentId) => {
+    (documentId: Identifier) => {
       if (!documentId) {
         return;
       }
-      openDetailPanel({ documentIds: [documentId] });
+      openDetailPanel(documentId);
     },
     [openDetailPanel],
   );
diff --git a/frontend/src/hooks/documents/useDocumentsWorkspace.ts b/frontend/src/hooks/documents/useDocumentsWorkspace.ts
index 4f6f657..ae983cd 100644
--- a/frontend/src/hooks/documents/useDocumentsWorkspace.ts
+++ b/frontend/src/hooks/documents/useDocumentsWorkspace.ts
@@ -257,7 +257,6 @@ const useDocumentsWorkspace = ({
     selectedDocumentIds,
     selectedFolderIds,
     setSelectedEntries,
-    selectionOrder,
     setSelectionOrder,
     selectionOrderRef,
     selectionAnchorRef,
@@ -1074,8 +1073,6 @@ const useDocumentsWorkspace = ({
     resolveFolderPath,
   } = useDetailWorkspace({
     documents: viewDocuments,
-    selectionOrder,
-    selectedDocumentIds,
     documentLookup,
     folderNodes,
     ensureFolderData,