diff --git a/frontend/src/documents/data/useDocumentMutations.ts b/frontend/src/documents/data/useDocumentMutations.ts
index c56628b..6ccbe5a 100644
--- a/frontend/src/documents/data/useDocumentMutations.ts
+++ b/frontend/src/documents/data/useDocumentMutations.ts
@@ -37,8 +37,6 @@ type EnsureFolderData = (
   options?: { includeDocuments?: boolean },
 ) => Promise<FolderContents>;
 
-type ApplySelectedFolder = (folderId: FolderId, contents?: FolderContents | null) => void;
-
 type RemoveDocumentsFromCaches = (documentIds: DocumentId[]) => void;
 
 type CloseDocumentPreview = () => void;
@@ -86,7 +84,6 @@ interface UseDocumentMutationsArgs {
   selectedFolder: FolderId;
   setSelectedFolder: Dispatch<SetStateAction<FolderId>>;
   setDocuments: Dispatch<SetStateAction<Document[]>>;
-  setFolderContents: Dispatch<SetStateAction<Map<FolderId, FolderContents>>>;
   setSearchResultIds: Dispatch<SetStateAction<DocumentId[] | null>>;
   setSelectedEntries: Dispatch<SetStateAction<string[]>>;
   setSelectionOrder: Dispatch<SetStateAction<string[]>>;
@@ -99,7 +96,6 @@ interface UseDocumentMutationsArgs {
   notifyApiError: NotifyApiError;
   setStatusMessage: SetStatusMessage;
   mapDocumentCaches: MapDocumentCaches;
-  applySelectedFolder: ApplySelectedFolder;
   folderNodes: Map<FolderId, FolderNode>;
   setFolderNodes: Dispatch<SetStateAction<Map<FolderId, FolderNode>>>;
   removeDocumentsFromCaches: RemoveDocumentsFromCaches;
@@ -159,7 +155,6 @@ const useDocumentMutations = ({
   selectedFolder,
   setSelectedFolder,
   setDocuments,
-  setFolderContents,
   setSearchResultIds,
   setSelectedEntries,
   setSelectionOrder,
@@ -172,7 +167,6 @@ const useDocumentMutations = ({
   notifyApiError,
   setStatusMessage,
   mapDocumentCaches,
-  applySelectedFolder,
   folderNodes,
   setFolderNodes,
   removeDocumentsFromCaches,
@@ -291,26 +285,8 @@ const useDocumentMutations = ({
             return filtered.length === prev.length ? prev : filtered;
           });
           setDocuments((prev) => prev.filter((doc) => !uniqueIdSet.has(doc.id as DocumentId)));
-          setFolderContents((prev: Map<FolderId, FolderContents>) => {
-            if (!prev.size) {
-              return prev;
-            }
-            let changed = false;
-            const next = new Map<FolderId, FolderContents>(prev);
-            movedDocs.forEach(({ id, sourceFolderId }) => {
-              const sourceKey = (sourceFolderId || 'root') as FolderId;
-              const entry = next.get(sourceKey);
-              if (!entry?.documents?.length) {
-                return;
-              }
-              const filteredDocs = entry.documents.filter((doc) => doc.id !== id);
-              if (filteredDocs.length !== entry.documents.length) {
-                changed = true;
-                next.set(sourceKey, { ...entry, documents: filteredDocs });
-              }
-            });
-            return changed ? next : prev;
-          });
+          setDocuments((prev) => prev.filter((doc) => !uniqueIdSet.has(doc.id as DocumentId)));
+          // setFolderContents removed as we don't hold full cache anymore
 
           setSelectedEntries((prev) => pruneRow(prev));
           setSelectionOrder((prev) => pruneRow(prev));
@@ -350,7 +326,6 @@ const useDocumentMutations = ({
       selectedFolder,
       setSearchResultIds,
       setDocuments,
-      setFolderContents,
       setSelectedEntries,
       setSelectionOrder,
       selectionOrderRef,
@@ -696,22 +671,17 @@ const useDocumentMutations = ({
               });
             }
           }
-          return next;
         });
 
-        setFolderContents((prev: Map<FolderId, FolderContents>) => {
-          const next = new Map<FolderId, FolderContents>(prev);
-          next.delete(folderId);
-          return next;
-        });
+        // setFolderContents removed
 
         if (selectedFolder === folderId) {
           const node = folderNodes.get(folderId);
           const parentId = node?.parentId || 'root';
           setSelectedFolder(parentId);
-          const parentContents = await ensureFolderData(parentId);
-          applySelectedFolder(parentId, parentContents);
+          // ensureFolderData(parentId) will be called by useDocumentsWorkspace effect when selectedFolder changes
         } else if (selectedFolder !== 'root') {
+          // If deleted folder was not selected, just check if we need to refresh (maybe redundant)
           await ensureFolderData(selectedFolder);
         }
 
@@ -734,9 +704,7 @@ const useDocumentMutations = ({
       selectedFolder,
       folderNodes,
       setSelectedFolder,
-      applySelectedFolder,
       setFolderNodes,
-      setFolderContents,
       notifyApiError,
       setStatusMessage,
     ],
diff --git a/frontend/src/documents/data/useDocumentsWorkspace.ts b/frontend/src/documents/data/useDocumentsWorkspace.ts
index ca2864e..62b4534 100644
--- a/frontend/src/documents/data/useDocumentsWorkspace.ts
+++ b/frontend/src/documents/data/useDocumentsWorkspace.ts
@@ -18,7 +18,7 @@ import useApiError from '../../hooks/useApiError';
 import TagManager from '../../lib/assets/TagManager';
 import { useManagementModals } from '../../app/useManagementModals';
 import { useAppDispatch, useAppState } from '../../lib/store/appState';
-import { fetchAsset } from '../../lib/api/apiClient';
+import { fetchAsset, listFolderContents } from '../../lib/api/apiClient';
 import { useApi } from '../../lib/context/ApiContext';
 import { useWorkspaceSelection } from '../../app/useWorkspaceSelection';
 import { useEntryPointer as useEntryPointerCore } from '../features/selection/useEntryPointer';
@@ -34,7 +34,12 @@ import {
   createRootNode,
   mergeAssetIntoDocument,
 } from '../../app/workspaceUtils';
-import { createDocumentEntryKey, createFolderEntryKey } from '../../app/entryKey';
+import {
+  createDocumentEntryKey,
+  createFolderEntryKey,
+  isFolderEntry,
+  isDocumentEntry
+} from '../../app/entryKey';
 import useDocumentsSearch from '../../app/useDocumentsSearch';
 import { useStatusToast, type ToastVariant } from '../../lib/context/StatusToastContext';
 import useAuthManager from './useAuthManager';
@@ -281,27 +286,6 @@ const useDocumentsWorkspace = ({
     configureSelectionEnvironment,
   } = selection;
 
-  const selectionHelpers = useMemo(
-    () => ({
-      setSelectedEntries,
-      setSelectionOrder,
-      selectionOrderRef,
-      selectionAnchorRef,
-      setFocusedDocumentId,
-      focusedDocumentId,
-      selectionInitializedRef,
-    }),
-    [
-      setSelectedEntries,
-      setSelectionOrder,
-      selectionOrderRef,
-      selectionAnchorRef,
-      setFocusedDocumentId,
-      focusedDocumentId,
-      selectionInitializedRef,
-    ],
-  );
-
   const [folderContents, setFolderContents] = useState<Map<FolderNodeId, FolderContentsEntry>>(
     () => new Map(),
   );
@@ -339,27 +323,102 @@ const useDocumentsWorkspace = ({
     setFolderNodes,
     selectedFolder,
     setSelectedFolder,
-    currentFolder,
-    setCurrentFolder,
-    currentSubfolders,
-    setCurrentSubfolders,
     currentFolderName,
     folderOptions,
     folderLabelMap,
-    applySelectedFolder,
-    ensureFolderData,
     isInvalidFolderDrop,
   } = useFolderTree({
     initialSelectedFolder: routeFolderId || 'root',
-    documentsSortFieldRef: activeSortFieldRef,
-    documentsSortDirectionRef: activeSortDirectionRef,
-    selectionHelpers,
-    setDocuments,
-    setFolderContents,
-    folderContentsRef,
     foldersManager,
   });
 
+  const [currentFolder, setCurrentFolder] = useState<FolderContentsEntry['folder'] | null>(null);
+  const [currentSubfolders, setCurrentSubfolders] = useState<FolderContentsEntry['subfolders']>([]);
+
+  const ensureFolderData = useCallback(
+    async (
+      folderId: FolderNodeId,
+      options: { includeDocuments?: boolean } = {}
+    ) => {
+      try {
+        const path = folderId === 'root' ? 'root' : folderId;
+        const includeDocuments = options.includeDocuments ?? true;
+        const params: Record<string, unknown> = {
+          include_documents: includeDocuments,
+          sort: activeSortFieldRef.current,
+          dir: activeSortDirectionRef.current,
+        };
+
+        const data = await listFolderContents(path, params);
+
+        // Only update UI state if we are fetching for the currently selected folder
+        if (folderId === selectedFolder) {
+          // Update documents state if included
+          if (includeDocuments) {
+            setDocuments((data.documents || []) as Document[]);
+          }
+          setCurrentSubfolders((data.subfolders || []) as any[]);
+          setCurrentFolder(data.folder || null);
+
+          // Update selection state based on new documents
+          if (includeDocuments) {
+            const docs = (data.documents || []) as Document[];
+            const subfolders = (data.subfolders || []) as any[];
+
+            const availableDocKeys = docs
+              .map((doc) => createDocumentEntryKey(doc?.id as Identifier))
+              .filter(Boolean);
+            const availableDocKeySet = new Set(availableDocKeys);
+            const availableFolderKeys = new Set(
+              subfolders
+                .map((folder) => createFolderEntryKey(folder?.id as Identifier))
+                .filter(Boolean),
+            );
+
+            setSelectedEntries((previous) => {
+              const previousFolderKeys = previous
+                .filter(isFolderEntry)
+                .filter((key) => availableFolderKeys.has(key));
+              const previousDocKeys = previous.filter(isDocumentEntry);
+              const nextDocKeys = previousDocKeys.filter((key) => availableDocKeySet.has(key));
+              const mergedSelection = [...previousFolderKeys, ...nextDocKeys];
+              return mergedSelection;
+            });
+          }
+        }
+        return data; // Return data for consumers (e.g. useDocumentMutations)
+      } catch (error) {
+        notifyApiError(error, 'Failed to fetch folder contents');
+        throw error;
+      }
+    },
+    [
+      activeSortFieldRef,
+      activeSortDirectionRef,
+      setDocuments,
+      setCurrentFolder,
+      setSelectedEntries,
+      notifyApiError,
+      setCurrentSubfolders,
+      selectedFolder,
+    ]
+  );
+
+  // Reactively fetch documents when selectedFolder changes
+  useEffect(() => {
+    if (selectedFolder) {
+      ensureFolderData(selectedFolder);
+    }
+  }, [selectedFolder, ensureFolderData]);
+
+  // Also re-fetch when sort changes
+  useEffect(() => {
+    if (selectedFolder && sortRefreshReadyRef?.current) {
+      ensureFolderData(selectedFolder);
+    }
+  }, [documentsSortField, documentsSortDirection, selectedFolder, ensureFolderData, sortRefreshReadyRef]);
+
+
   const {
     searchQuery,
     setSearchQuery,
@@ -426,7 +485,7 @@ const useDocumentsWorkspace = ({
     () =>
       showingSearchResults
         ? []
-        : currentSubfolders
+        : (currentSubfolders || [])
           .map((folder) => createFolderEntryKey(folder.id))
           .filter(Boolean),
     [showingSearchResults, currentSubfolders],
@@ -577,9 +636,10 @@ const useDocumentsWorkspace = ({
   );
 
   const refreshCurrentFolder = useCallback(async () => {
-    const contents = await ensureFolderData(selectedFolder);
-    applySelectedFolder(selectedFolder, contents);
-  }, [selectedFolder, ensureFolderData, applySelectedFolder]);
+    if (selectedFolder) {
+      await ensureFolderData(selectedFolder);
+    }
+  }, [selectedFolder, ensureFolderData]);
 
   const {
     handleBulkTagAddFromDetail,
@@ -601,15 +661,16 @@ const useDocumentsWorkspace = ({
     uploadQueue,
     clearUploadQueue,
     resetUploadsState,
+    handleFileSelection,
   } = useDocumentUploads({
     token,
     selectedFolder,
     currentFolderName,
     ensureFolderData,
     refreshCurrentFolder,
+    shellRef,
     notifyApiError,
     setStatusMessage,
-    shellRef,
   });
 
   const {
@@ -618,15 +679,15 @@ const useDocumentsWorkspace = ({
     handleFolderDragStart,
     handleFolderDragEnd,
   } = useDocumentDragHandlers({
+    documentLookup,
+    setDraggedDocumentIds,
+    setDraggedFolderId,
+    documentsViewMode,
     selectedEntries,
     selectedDocumentIds,
     selectedFolderIds,
     applySelection,
     handleEntrySelection,
-    documentLookup,
-    setDraggedDocumentIds,
-    setDraggedFolderId,
-    documentsViewMode,
   });
 
   useEffect(() => {
@@ -649,7 +710,6 @@ const useDocumentsWorkspace = ({
   const resetWorkspaceState = useCallback(() => {
     const rootNode = createRootNode();
     setFolderNodes(new Map([[rootNode.id, rootNode]]));
-    setFolderContents(new Map());
     setSelectedFolder('root');
     setCurrentFolder(null);
     setCurrentSubfolders([]);
@@ -687,7 +747,7 @@ const useDocumentsWorkspace = ({
     setSelectedEntries,
     setSelectionOrder,
     setFolderNodes,
-    setFolderContents,
+    // setFolderContents,
     setSelectedFolder,
     setCurrentFolder,
     setCurrentSubfolders,
@@ -730,35 +790,11 @@ const useDocumentsWorkspace = ({
         return filtered.length === prev.length ? prev : filtered;
       });
 
-      setFolderContents((prev: Map<FolderNodeId, FolderContentsEntry>) => {
-        if (!prev.size) {
-          return prev;
-        }
-        let changed = false;
-        const next = new Map<FolderNodeId, FolderContentsEntry>();
-        prev.forEach((contents, key) => {
-          const docs = Array.isArray(contents?.documents) ? contents.documents : null;
-          if (!docs || docs.length === 0) {
-            next.set(key, contents);
-            return;
-          }
-          const filtered = docs.filter((doc) => !idSet.has(doc.id));
-          if (filtered.length !== docs.length) {
-            changed = true;
-            next.set(key, { ...contents, documents: filtered });
-          } else {
-            next.set(key, contents);
-          }
-        });
-        return changed ? next : prev;
-      });
-
       removeDocumentsFromLookup(Array.from(idSet));
     },
     [
       setDocuments,
       setSearchResultIds,
-      setFolderContents,
       removeDocumentsFromLookup,
     ],
   );
@@ -780,7 +816,6 @@ const useDocumentsWorkspace = ({
     selectedFolder,
     setSelectedFolder,
     setDocuments,
-    setFolderContents,
     setSearchResultIds,
     setSelectedEntries,
     setSelectionOrder,
@@ -793,7 +828,6 @@ const useDocumentsWorkspace = ({
     notifyApiError,
     setStatusMessage,
     mapDocumentCaches,
-    applySelectedFolder,
     folderNodes,
     setFolderNodes,
     removeDocumentsFromCaches,
@@ -822,14 +856,9 @@ const useDocumentsWorkspace = ({
     setFolderNodes,
     selectedFolder,
     setSelectedFolder,
-    ensureFolderData,
-    applySelectedFolder,
     notifyApiError,
     setStatusMessage,
-    setFolderContents,
     setCurrentFolder,
-    setSearchResultIds,
-    isFilterActive,
     navigate,
     handleFileDrop,
     moveDocumentsToFolder,
@@ -883,8 +912,8 @@ const useDocumentsWorkspace = ({
       return;
     }
 
-    const hasData = folderContents.has(targetParam);
-    if (targetParam !== selectedFolder || !hasData) {
+    // Checking cache (folderContents) is removed, now we rely on selectedFolder effect to fetch.
+    if (targetParam !== selectedFolder) {
       selectFolder(targetParam, { immediate: true });
     }
   }, [
@@ -893,7 +922,6 @@ const useDocumentsWorkspace = ({
     routeFolderId,
     routeDocumentId,
     selectedFolder,
-    folderContents,
     isFilterActive,
     selectFolder,
   ]);
@@ -1302,6 +1330,7 @@ const useDocumentsWorkspace = ({
     tenants: tenantOptions,
     tenantOptions,
     handleTenantSelect,
+    handleFileSelection,
   };
 
   // hook callers handle rendering / routing
diff --git a/frontend/src/documents/features/folders/useFolderTree.ts b/frontend/src/documents/features/folders/useFolderTree.ts
index 4cdc4e6..77d953a 100644
--- a/frontend/src/documents/features/folders/useFolderTree.ts
+++ b/frontend/src/documents/features/folders/useFolderTree.ts
@@ -1,51 +1,11 @@
-import { useCallback, useEffect, useMemo, useRef, useState } from 'react';
-import type { Dispatch, MutableRefObject, SetStateAction } from 'react';
+import { useCallback, useEffect, useMemo, useState } from 'react';
 import { createRootNode, DEFAULT_FOLDER_NAME, flattenFolderTree } from '../../../app/workspaceUtils';
-import { listFolderContents } from '../../../lib/api/apiClient';
-import {
-  getEntryId,
-  isDocumentEntry,
-  isFolderEntry,
-  createDocumentEntryKey,
-  createFolderEntryKey,
-} from '../../../app/entryKey';
-import type { FolderNodeId, Identifier, FolderId } from '../../../types/identifiers';
-import type { Document, Folder, FolderContents } from '../../../types/documents';
+import type { FolderNodeId, FolderId } from '../../../types/identifiers';
+import type { FolderNode } from '../../../types/documents';
 import type FoldersManager from '../../FoldersManager';
 
-interface FolderContentsEntry extends FolderContents {
-  __includesDocuments?: boolean;
-  __sortField?: string | null;
-  __sortDirection?: string | null;
-  [key: string]: unknown;
-}
-
-interface FolderTreeNode extends Folder {
-  id: FolderNodeId;
-  children: FolderNodeId[];
-  expanded?: boolean;
-  loaded?: boolean;
-  hasChildren?: boolean;
-  parentId?: FolderNodeId;
-}
-
-interface SelectionHelpers {
-  focusedDocumentId: Identifier | null;
-  setFocusedDocumentId: Dispatch<SetStateAction<Identifier | null>>;
-  setSelectedEntries: Dispatch<SetStateAction<string[]>>;
-  setSelectionOrder: Dispatch<SetStateAction<string[]>>;
-  selectionOrderRef: MutableRefObject<string[] | null>;
-  selectionAnchorRef: MutableRefObject<string | null>;
-}
-
 interface UseFolderTreeOptions {
   initialSelectedFolder?: FolderNodeId;
-  documentsSortFieldRef: MutableRefObject<string>;
-  documentsSortDirectionRef: MutableRefObject<string>;
-  selectionHelpers: SelectionHelpers;
-  setDocuments: Dispatch<SetStateAction<Document[]>>;
-  setFolderContents: Dispatch<SetStateAction<Map<FolderNodeId, FolderContentsEntry>>>;
-  folderContentsRef: MutableRefObject<Map<FolderNodeId, FolderContentsEntry>>;
   foldersManager?: FoldersManager;
 }
 
@@ -56,16 +16,10 @@ interface FolderOption {
 
 const useFolderTree = ({
   initialSelectedFolder = 'root',
-  documentsSortFieldRef,
-  documentsSortDirectionRef,
-  selectionHelpers,
-  setDocuments,
-  setFolderContents,
-  folderContentsRef,
   foldersManager,
 }: UseFolderTreeOptions) => {
-  const [folderNodes, setFolderNodes] = useState<Map<FolderNodeId, FolderTreeNode>>(() => {
-    const rootNode = createRootNode() as FolderTreeNode;
+  const [folderNodes, setFolderNodes] = useState<Map<FolderNodeId, FolderNode>>(() => {
+    const rootNode = createRootNode() as FolderNode;
     return new Map([[rootNode.id, rootNode]]);
   });
 
@@ -110,7 +64,7 @@ const useFolderTree = ({
           const root = next.get('root');
           if (root) {
             next.set('root', {
-              ...(root as FolderTreeNode),
+              ...(root as FolderNode),
               children: rootChildren,
               hasChildren: rootChildren.length > 0,
               loaded: true,
@@ -126,158 +80,6 @@ const useFolderTree = ({
   }, [foldersManager]);
 
   const [selectedFolder, setSelectedFolder] = useState<FolderNodeId>(initialSelectedFolder || 'root');
-  const [currentFolder, setCurrentFolder] = useState<Folder | null>(null);
-  const [currentSubfolders, setCurrentSubfolders] = useState<Folder[]>([]);
-
-  const {
-    focusedDocumentId,
-    setFocusedDocumentId,
-    setSelectedEntries,
-    setSelectionOrder,
-    selectionOrderRef,
-    selectionAnchorRef,
-  } = selectionHelpers;
-
-  const focusedDocumentIdRef = useRef(focusedDocumentId);
-  useEffect(() => {
-    focusedDocumentIdRef.current = focusedDocumentId;
-  }, [focusedDocumentId]);
-
-  const applySelectedFolder = useCallback(
-    (folderId: FolderNodeId, contents?: FolderContentsEntry | null) => {
-      const subfolders = Array.isArray(contents?.subfolders) ? contents.subfolders : [];
-      const docs = Array.isArray(contents?.documents) ? contents.documents : [];
-      const folderInfo = contents?.folder ?? null;
-
-      setCurrentSubfolders(subfolders);
-      setDocuments(docs);
-      setCurrentFolder(folderInfo);
-
-      const availableDocKeys = docs
-        .map((doc) => createDocumentEntryKey((doc as Document)?.id as Identifier))
-        .filter(Boolean);
-      const availableDocKeySet = new Set(availableDocKeys);
-      const availableFolderKeys = new Set(
-        subfolders
-          .map((folder) => createFolderEntryKey(folder?.id as Identifier))
-          .filter(Boolean),
-      );
-
-      let nextDocKeys: string[] = [];
-      let mergedSelection: string[] = [];
-
-      setSelectedEntries((previous) => {
-        const previousFolderKeys = previous
-          .filter(isFolderEntry)
-          .filter((key) => availableFolderKeys.has(key));
-        const previousDocKeys = previous.filter(isDocumentEntry);
-        nextDocKeys = previousDocKeys.filter((key) => availableDocKeySet.has(key));
-        mergedSelection = [...previousFolderKeys, ...nextDocKeys];
-        return mergedSelection;
-      });
-
-      const nextFocus = (() => {
-        const currentFocusedId = focusedDocumentIdRef.current;
-        if (currentFocusedId) {
-          const currentFocusedKey = createDocumentEntryKey(currentFocusedId);
-          if (currentFocusedKey && availableDocKeySet.has(currentFocusedKey)) {
-            return currentFocusedId;
-          }
-        }
-        if (nextDocKeys.length) {
-          const lastDocKey = nextDocKeys[nextDocKeys.length - 1];
-          return getEntryId(lastDocKey) || null;
-        }
-        return null;
-      })();
-
-      setFocusedDocumentId(nextFocus);
-      const nextAnchor = mergedSelection.length ? mergedSelection[mergedSelection.length - 1] : null;
-      selectionAnchorRef.current = nextAnchor;
-      selectionOrderRef.current = mergedSelection;
-      setSelectionOrder(mergedSelection);
-    },
-    [
-      selectionAnchorRef,
-      selectionOrderRef,
-      setDocuments,
-      setFocusedDocumentId,
-      setSelectedEntries,
-      setSelectionOrder,
-    ],
-  );
-
-  const ensureFolderData = useCallback(
-    async (
-      folderId: FolderNodeId,
-      {
-        includeDocuments = true,
-        sortField = documentsSortFieldRef.current,
-        sortDirection = documentsSortDirectionRef.current,
-      }: {
-        includeDocuments?: boolean;
-        sortField?: string;
-        sortDirection?: string;
-      } = {},
-    ): Promise<FolderContentsEntry> => {
-      const cached = folderContentsRef.current.get(folderId);
-      const cachedSortField = cached?.__sortField || documentsSortFieldRef.current;
-      const cachedSortDirection = cached?.__sortDirection || documentsSortDirectionRef.current;
-      const cachedSortMatches = cachedSortField === sortField && cachedSortDirection === sortDirection;
-
-      if (cached) {
-        const includesDocuments = Boolean(cached.__includesDocuments);
-        if (!includeDocuments || (includesDocuments && cachedSortMatches)) {
-          return cached;
-        }
-      }
-
-      // We use listFolderContents purely for Documents now, assuming Tree is authoritative for subfolders.
-      const path = folderId === 'root' ? 'root' : folderId;
-      const params: Record<string, unknown> = {};
-      if (!includeDocuments) {
-        params.include_documents = false;
-      } else {
-        params.sort = sortField;
-        params.dir = sortDirection;
-      }
-
-      const data = await listFolderContents(path, params);
-
-      const enriched = {
-        ...data,
-        documents: (data.documents || []) as Document[],
-        __includesDocuments: includeDocuments,
-        __sortField: includeDocuments ? sortField : cachedSortField,
-        __sortDirection: includeDocuments ? sortDirection : cachedSortDirection,
-      };
-
-      setFolderContents((prev: Map<FolderNodeId, FolderContentsEntry>) => {
-        const next = new Map<FolderNodeId, FolderContentsEntry>(prev);
-        if (includeDocuments) {
-          next.set(folderId, enriched);
-        } else {
-          const existing = next.get(folderId);
-          next.set(folderId, {
-            ...enriched,
-            documents: existing?.__includesDocuments ? existing.documents : (enriched.documents as Document[]),
-            __includesDocuments: existing?.__includesDocuments || false,
-          });
-        }
-        folderContentsRef.current = next;
-        return next;
-      });
-
-      return enriched;
-    },
-    [
-      documentsSortDirectionRef,
-      documentsSortFieldRef,
-      setFolderContents,
-      folderContentsRef,
-      // Removed foldersManager dependency as we don't call it here anymore
-    ],
-  );
 
   const isInvalidFolderDrop = useCallback(
     (sourceId: FolderNodeId | null, targetId: FolderNodeId | null) => {
@@ -298,7 +100,7 @@ const useFolderTree = ({
         }
         const node = folderNodes.get(current);
         if (!node) break;
-        current = node.parentId ?? 'root';
+        current = (node.parentId ?? 'root') as FolderNodeId;
       }
       return false;
     },
@@ -306,18 +108,16 @@ const useFolderTree = ({
   );
 
   const resetFolderTreeState = useCallback(() => {
-    const rootNode = createRootNode() as FolderTreeNode;
-    setFolderNodes(new Map<FolderNodeId, FolderTreeNode>([[rootNode.id, rootNode]]));
-    setFolderContents(new Map<FolderNodeId, FolderContentsEntry>());
+    const rootNode = createRootNode() as FolderNode;
+    setFolderNodes(new Map<FolderNodeId, FolderNode>([[rootNode.id, rootNode]]));
     setSelectedFolder('root');
-    setCurrentFolder(null);
-    setCurrentSubfolders([]);
-  }, [setFolderContents]);
+  }, []);
 
   const currentFolderName = useMemo(() => {
-    if (selectedFolder === 'root' || !currentFolder) return DEFAULT_FOLDER_NAME;
-    return currentFolder.name;
-  }, [selectedFolder, currentFolder]);
+    if (selectedFolder === 'root') return DEFAULT_FOLDER_NAME;
+    const node = folderNodes.get(selectedFolder);
+    return node?.name || DEFAULT_FOLDER_NAME;
+  }, [selectedFolder, folderNodes]);
 
   const folderOptions: FolderOption[] = useMemo(() => {
     const cache = new Map<FolderNodeId, string>();
@@ -376,15 +176,9 @@ const useFolderTree = ({
     setFolderNodes,
     selectedFolder,
     setSelectedFolder,
-    currentFolder,
-    setCurrentFolder,
-    currentSubfolders,
-    setCurrentSubfolders,
     currentFolderName,
     folderOptions,
     folderLabelMap,
-    applySelectedFolder,
-    ensureFolderData,
     isInvalidFolderDrop,
     resetFolderTreeState,
   };
diff --git a/frontend/src/documents/features/folders/useFolderTreeActions.ts b/frontend/src/documents/features/folders/useFolderTreeActions.ts
index de82706..360dd15 100644
--- a/frontend/src/documents/features/folders/useFolderTreeActions.ts
+++ b/frontend/src/documents/features/folders/useFolderTreeActions.ts
@@ -8,31 +8,10 @@ import {
   renameFolder as renameFolderRequest,
 } from '../../../lib/api/apiClient';
 import type { FolderId } from '../../../types/identifiers';
-import type { MessageOptions } from '../../../types/documents';
+import type { MessageOptions, FolderNode } from '../../../types/documents';
 
 type FolderKey = FolderId | 'root';
 
-interface FolderNode {
-  id: FolderKey;
-  name?: string;
-  parentId?: FolderKey | null;
-  children: FolderId[];
-  expanded?: boolean;
-  loaded?: boolean;
-  hasChildren?: boolean;
-}
-
-interface FolderContentsState {
-  folder?: { id: FolderKey; name?: string };
-  subfolders?: any[];
-  documents?: any[];
-  [key: string]: unknown;
-}
-
-interface EnsureFolderOptions {
-  includeDocuments?: boolean;
-}
-
 interface LoadFolderOptions {
   preserveSearch?: boolean;
 }
@@ -55,16 +34,9 @@ interface UseFolderTreeActionsOptions {
   setFolderNodes: (updater: (prev: Map<FolderKey, FolderNode>) => Map<FolderKey, FolderNode>) => void;
   selectedFolder: FolderKey;
   setSelectedFolder: (folderId: FolderKey) => void;
-  ensureFolderData: (folderId: FolderKey, options?: EnsureFolderOptions) => Promise<any>;
-  applySelectedFolder: (folderId: FolderKey, contents: any) => void;
   notifyApiError: (error: unknown, message?: string) => void;
   setStatusMessage: (message: string, level?: string) => void;
-  setFolderContents: (
-    updater: (prev: Map<FolderKey, FolderContentsState>) => Map<FolderKey, FolderContentsState>,
-  ) => void;
   setCurrentFolder: (updater: (prev: any) => any) => void;
-  setSearchResultIds: (value: any) => void;
-  isFilterActive: boolean;
   navigate?: (path: string, options?: { replace?: boolean }) => void;
   handleFileDrop: (dataTransfer: DataTransfer, folderId: FolderKey) => Promise<void> | void;
   moveDocumentsToFolder: (docIds: FolderId[], folderId: FolderKey) => Promise<void>;
@@ -82,14 +54,9 @@ const useFolderTreeActions = ({
   setFolderNodes,
   selectedFolder,
   setSelectedFolder,
-  ensureFolderData,
-  applySelectedFolder,
   notifyApiError,
   setStatusMessage,
-  setFolderContents,
   setCurrentFolder,
-  setSearchResultIds,
-  isFilterActive,
   navigate,
   handleFileDrop,
   moveDocumentsToFolder,
@@ -165,15 +132,7 @@ const useFolderTreeActions = ({
           return next;
         });
 
-        const refreshTargets = new Set([previousParentKey, targetKey]);
-        await Promise.all(
-          Array.from(refreshTargets).map((key) =>
-            ensureFolderData(key),
-          ),
-        );
-
         if (selectedFolder === folderId) {
-          await ensureFolderData(folderId);
           setSelectedFolder(folderId);
         }
 
@@ -181,17 +140,9 @@ const useFolderTreeActions = ({
       } catch (error) {
         const message = error.response?.data?.error || 'Failed to move folder.';
         notifyApiError(error, message);
-
-        const refreshTargets = new Set([previousParentKey, targetKey]);
-        await Promise.all(
-          Array.from(refreshTargets).map((key) =>
-            ensureFolderData(key),
-          ),
-        );
       }
     },
     [
-      ensureFolderData,
       folderNodes,
       notifyApiError,
       selectedFolder,
@@ -202,35 +153,12 @@ const useFolderTreeActions = ({
   );
 
   const loadFolder = useCallback(
-    async (folderId: FolderKey | null, { preserveSearch = false }: LoadFolderOptions = {}) => {
+    async (folderId: FolderKey | null, { preserveSearch: _preserveSearch = false }: LoadFolderOptions = {}) => {
       const targetId = folderId || 'root';
       setSelectedFolder(targetId);
-      try {
-        const contents = await ensureFolderData(targetId);
-        if (targetId !== 'root') {
-          try {
-            await ensureFolderData('root', {
-              includeDocuments: false,
-            });
-          } catch (error) {
-            console.warn('Failed to refresh root folder tree', error);
-          }
-        }
-        applySelectedFolder(targetId, contents);
-        if (!preserveSearch) {
-          setSearchResultIds(null);
-        }
-      } catch (error) {
-        notifyApiError(error, 'Failed to load folder contents.');
-      }
+      // Data fetching is now reactive in the parent component based on selectedFolder
     },
-    [
-      applySelectedFolder,
-      ensureFolderData,
-      notifyApiError,
-      setSearchResultIds,
-      setSelectedFolder,
-    ],
+    [setSelectedFolder],
   );
 
   const selectFolder = useCallback(
@@ -238,8 +166,7 @@ const useFolderTreeActions = ({
       const targetId = folderId && folderId !== 'root' ? folderId : 'root';
 
       if (!navigate || immediate) {
-        await loadFolder(targetId, { preserveSearch: isFilterActive });
-        setSelectedFolder(targetId);
+        await loadFolder(targetId);
         return;
       }
 
@@ -247,10 +174,8 @@ const useFolderTreeActions = ({
       navigate(path, { replace });
     },
     [
-      isFilterActive,
       loadFolder,
       navigate,
-      setSelectedFolder,
     ],
   );
 
@@ -277,19 +202,6 @@ const useFolderTreeActions = ({
           return next;
         });
 
-        setFolderContents((prev) => {
-          if (!prev.has(folderId)) {
-            return prev;
-          }
-          const next = new Map(prev);
-          const existing = next.get(folderId) || {};
-          const folderInfo = existing.folder
-            ? { ...existing.folder, name: trimmed }
-            : { id: folderId, name: trimmed };
-          next.set(folderId, { ...existing, folder: folderInfo });
-          return next;
-        });
-
         setCurrentFolder((prev) => (prev?.id === folderId ? { ...prev, name: trimmed } : prev));
         setStatusMessage('Folder renamed.', 'success');
         return true;
@@ -302,7 +214,6 @@ const useFolderTreeActions = ({
     [
       notifyApiError,
       setCurrentFolder,
-      setFolderContents,
       setFolderNodes,
       setStatusMessage,
       token,
@@ -361,10 +272,6 @@ const useFolderTreeActions = ({
           return next;
         });
 
-        // Refresh the parent folder to ensure consistency
-        const refreshTarget = targetParentId || 'root';
-        await ensureFolderData(refreshTarget);
-
         await selectFolder(folderData.id, { immediate: true });
         succeeded = true;
         return true;
@@ -380,7 +287,6 @@ const useFolderTreeActions = ({
       }
     },
     [
-      ensureFolderData,
       notifyApiError,
       selectFolder,
       selectedFolder,
@@ -407,16 +313,6 @@ const useFolderTreeActions = ({
       }
 
       try {
-        const contents = await ensureFolderData(folderId);
-        const hasChildren = (contents.subfolders || []).length > 0;
-        const hasDocs = (contents.documents || []).length > 0;
-        if (hasChildren || hasDocs) {
-          if (showMessage) {
-            setStatusMessage('Folder must be empty before it can be deleted.', 'error');
-          }
-          return false;
-        }
-
         await deleteFolder(folderId);
 
         setFolderNodes((prev) => {
@@ -438,20 +334,10 @@ const useFolderTreeActions = ({
           return next;
         });
 
-        setFolderContents((prev) => {
-          const next = new Map(prev);
-          next.delete(folderId);
-          return next;
-        });
-
         if (selectedFolder === folderId) {
           const node = folderNodes.get(folderId);
           const parentId = node?.parentId || 'root';
           setSelectedFolder(parentId);
-          const parentContents = await ensureFolderData(parentId);
-          applySelectedFolder(parentId, parentContents);
-        } else if (selectedFolder !== 'root') {
-          await ensureFolderData(selectedFolder);
         }
 
         if (showMessage) {
@@ -469,12 +355,9 @@ const useFolderTreeActions = ({
     },
     [
       token,
-      applySelectedFolder,
-      ensureFolderData,
       folderNodes,
       notifyApiError,
       selectedFolder,
-      setFolderContents,
       setFolderNodes,
       setSelectedFolder,
       setStatusMessage,
diff --git a/frontend/src/types/documents.ts b/frontend/src/types/documents.ts
index e4623bc..83001c1 100644
--- a/frontend/src/types/documents.ts
+++ b/frontend/src/types/documents.ts
@@ -14,13 +14,6 @@ export interface DocumentCorrespondent {
     count?: number;
 }
 
-export interface FolderContents {
-    folder: Folder | null;
-    documents: Document[];
-    subfolders: Folder[];
-    [key: string]: unknown;
-}
-
 /**
  * A tag entity as returned by the API (includes usage_count).
  * Use DocumentTag for the embedded version on documents.
@@ -111,3 +104,17 @@ export type DocumentsListEntry = FolderEntry | DocumentEntry;
 import type { MouseEvent } from 'react';
 
 export type FolderEventHandler = (folder: Folder, event: MouseEvent<HTMLElement>) => void;
+
+/**
+ * Represents a folder node in the UI tree structure (flat map representation).
+ */
+export interface FolderNode {
+    id: Identifier | 'root';
+    name?: string;
+    parentId?: Identifier | 'root' | null;
+    children: (Identifier | 'root')[];
+    expanded?: boolean;
+    loaded?: boolean;
+    hasChildren?: boolean;
+    [key: string]: unknown;
+}