diff --git a/frontend/src/app/LoginRoute.tsx b/frontend/src/app/LoginRoute.tsx
index df75310..1915506 100644
--- a/frontend/src/app/LoginRoute.tsx
+++ b/frontend/src/app/LoginRoute.tsx
@@ -1,3 +1,4 @@
+/* global PublicKeyCredentialCreationOptions, PublicKeyCredentialRequestOptions */
 import React, { useCallback, useEffect, useMemo, useRef, useState } from 'react';
 import { Navigate, useLocation } from 'react-router-dom';
 import LoginView from '../login/LoginView';
@@ -9,7 +10,15 @@ import {
   serializeAuthenticationCredential,
   serializeRegistrationCredential,
 } from '../utils/webauthn';
-import { api, useAppDispatch, useAppState } from './appState';
+import { useAppDispatch, useAppState } from './appState';
+import {
+  finishPasskeyLogin,
+  finishSignup,
+  performLogin,
+  selectTenant,
+  startPasskeyLogin,
+  startSignup,
+} from '../lib/apiClient';
 
 type StatusVariant = 'info' | 'success' | 'error';
 
@@ -28,6 +37,11 @@ interface TenantSelectionState {
   tenants?: TenantOption[];
 }
 
+type AuthResponse = {
+  access_token?: string;
+  tenant?: TenantOption | null;
+  tenants?: TenantOption[];
+};
 
 const LoginRoute: React.FC = () => {
   const appState = useAppState();
@@ -161,23 +175,19 @@ const LoginRoute: React.FC = () => {
 
       try {
         setSelectingTenantId(tenant.id);
-        const { data } = await api.post(
-          '/auth/select-tenant',
+        const data = await selectTenant(
           { tenant_id: tenant.id },
-          {
-            headers: {
-              Authorization: `Bearer ${tenantSelection.selectionToken}`,
-            },
-          },
-        );
+          tenantSelection.selectionToken,
+        ) as AuthResponse;
 
-        if (!data?.access_token) {
+        const accessToken = data?.access_token;
+        if (!accessToken) {
           throw new Error('Invalid tenant selection response.');
         }
 
         appDispatch({
           type: 'LOGIN_SUCCESS',
-          token: data.access_token,
+          token: accessToken,
           tenant: data.tenant || null,
         });
         setStatusMessage('Login successful.', 'success');
@@ -211,9 +221,9 @@ const LoginRoute: React.FC = () => {
       setPasskeyLoading(true);
       appDispatch({ type: 'LOGIN_REQUEST' });
       try {
-        const { data: startData } = await api.post('/auth/passkeys/login/start', { username });
-        const challengeId = startData.challengeId;
-        const publicKeyOptions = startData.publicKey;
+        const startData = await startPasskeyLogin(username);
+        const challengeId = (startData as { challengeId?: string })?.challengeId;
+        const publicKeyOptions = (startData as { publicKey?: PublicKeyCredentialRequestOptions })?.publicKey;
 
         if (!challengeId || !publicKeyOptions) {
           throw new Error('Invalid passkey challenge response.');
@@ -239,13 +249,13 @@ const LoginRoute: React.FC = () => {
           credential: serialized,
         };
 
-        const { data: finishData } = await api.post('/auth/passkeys/login/finish', finishPayload);
+        const finishData = await finishPasskeyLogin(finishPayload) as AuthResponse;
 
-        if (finishData?.access_token && Array.isArray(finishData?.tenants)) {
+        if (finishData?.access_token && Array.isArray(finishData.tenants)) {
           appDispatch({
             type: 'TENANT_SELECTION_REQUIRED',
             selectionToken: finishData.access_token,
-            tenants: finishData.tenants,
+            tenants: finishData.tenants || [],
           });
           setStatusMessage('Select a tenant to continue.', 'info');
           return;
@@ -322,16 +332,16 @@ const LoginRoute: React.FC = () => {
           payload.preferred_tenant_id = magicPreferredTenantId;
         }
 
-        const { data } = await api.post('/auth/login', payload);
+        const data = await performLogin(payload) as AuthResponse;
         if (cancelled) {
           return;
         }
 
-        if (data?.access_token && Array.isArray(data?.tenants)) {
+        if (data?.access_token && Array.isArray(data.tenants)) {
           appDispatch({
             type: 'TENANT_SELECTION_REQUIRED',
             selectionToken: data.access_token,
-            tenants: data.tenants,
+            tenants: data.tenants || [],
           });
           setStatusMessage('Select a tenant to continue.', 'info');
           return;
@@ -416,7 +426,10 @@ const LoginRoute: React.FC = () => {
 
       setSignupLoading(true);
       try {
-        const { data: startData } = await api.post('/auth/signup/start', { username });
+        const startData = await startSignup(username) as {
+          signup_token?: string;
+          challenge?: { challengeId?: string; publicKey?: PublicKeyCredentialCreationOptions };
+        };
         const signupToken = startData.signup_token;
         const challengePayload = startData.challenge;
         const challengeId = challengePayload?.challengeId;
@@ -446,13 +459,13 @@ const LoginRoute: React.FC = () => {
           credential: serialized,
         };
 
-        const { data: finishData } = await api.post('/auth/signup/finish', finishPayload);
+        const finishData = await finishSignup(finishPayload) as AuthResponse;
 
-        if (finishData?.access_token && Array.isArray(finishData?.tenants)) {
+        if (finishData?.access_token && Array.isArray(finishData.tenants)) {
           appDispatch({
             type: 'TENANT_SELECTION_REQUIRED',
             selectionToken: finishData.access_token,
-            tenants: finishData.tenants,
+            tenants: finishData.tenants || [],
           });
           setStatusMessage('Select a tenant to continue.', 'info');
           return;
diff --git a/frontend/src/app/SettingsRoute.tsx b/frontend/src/app/SettingsRoute.tsx
index fb86cb3..6e85bae 100644
--- a/frontend/src/app/SettingsRoute.tsx
+++ b/frontend/src/app/SettingsRoute.tsx
@@ -4,7 +4,6 @@ import { useAppShell } from '../appShellContext';
 import useApiTokens from '../settings/useApiTokens';
 import useCapabilitySets from '../settings/useCapabilitySets';
 import useCapabilities from '../settings/useCapabilities';
-import { api } from './appState';
 
 interface SettingsRouteProps {
   open?: boolean;
@@ -38,7 +37,7 @@ const SettingsRoute: React.FC<SettingsRouteProps> = ({ open = true, onClose }) =
     revoke: revokeToken,
     regenerate: regenerateToken,
     dismissSecret,
-  } = useApiTokens({ api, token, notifyApiError, setStatusMessage });
+  } = useApiTokens({ token, notifyApiError, setStatusMessage });
 
   const {
     capabilitySets,
@@ -51,7 +50,7 @@ const SettingsRoute: React.FC<SettingsRouteProps> = ({ open = true, onClose }) =
     createCapabilitySet,
     updateCapabilitySet,
     deleteCapabilitySet,
-  } = useCapabilitySets({ api, token, notifyApiError, setStatusMessage });
+  } = useCapabilitySets({ token, notifyApiError, setStatusMessage });
 
   const {
     capabilities,
diff --git a/frontend/src/app/appState.tsx b/frontend/src/app/appState.tsx
index e728128..cc05244 100644
--- a/frontend/src/app/appState.tsx
+++ b/frontend/src/app/appState.tsx
@@ -1,5 +1,6 @@
 import React, { useContext, useEffect, useMemo, useReducer } from 'react';
 import api from '../lib/api';
+import { listTenants } from '../lib/apiClient';
 
 type Tenant = Record<string, unknown> | null;
 
@@ -217,11 +218,11 @@ const AppStateProvider: React.FC<{ children?: React.ReactNode }> = ({ children }
       }
 
       try {
-        const { data } = await api.get('/tenants');
         if (!abort) {
+          const tenants = await listTenants();
           dispatch({
             type: 'SET_TENANTS',
-            tenants: Array.isArray(data?.tenants) ? data.tenants : [],
+            tenants,
           });
         }
       } catch (error) {
diff --git a/frontend/src/documents/hooks/useBulkDocumentActions.ts b/frontend/src/documents/hooks/useBulkDocumentActions.ts
index 47d436a..275c46f 100644
--- a/frontend/src/documents/hooks/useBulkDocumentActions.ts
+++ b/frontend/src/documents/hooks/useBulkDocumentActions.ts
@@ -1,12 +1,8 @@
 import { useCallback } from 'react';
+import { assignCorrespondentsBulk } from '../../lib/apiClient';
 
 export type Identifier = string | number;
 
-type ApiClient = {
-  post: <T = { data: unknown }>(url: string, payload: unknown) => Promise<{ data: T } | T>;
-  delete: (url: string) => Promise<unknown>;
-};
-
 type BulkAssignmentResponse = {
   assigned?: number;
   removed?: number;
@@ -17,7 +13,6 @@ type CorrespondentAssignment = {
 };
 
 interface UseBulkDocumentActionsArgs {
-  api: ApiClient;
   resolveTargetDocumentIds: (ids?: Identifier[] | null) => Identifier[];
   correspondentLookupByName: Map<string, { id?: Identifier }>;
   handleCorrespondentCreate: (payload: { name: string }) => Promise<{ id?: Identifier } | null>;
@@ -32,7 +27,6 @@ interface UseBulkDocumentActionsArgs {
 }
 
 const useBulkDocumentActions = ({
-  api,
   resolveTargetDocumentIds,
   correspondentLookupByName,
   handleCorrespondentCreate,
@@ -72,7 +66,7 @@ const useBulkDocumentActions = ({
         return;
     }
 
-    const response = await api.post<BulkAssignmentResponse>('/documents/bulk/correspondents', {
+    const response: BulkAssignmentResponse = await assignCorrespondentsBulk<BulkAssignmentResponse>({
       document_ids: targets,
       assignments: [
         {
@@ -82,7 +76,7 @@ const useBulkDocumentActions = ({
       action: 'add',
     });
 
-    const { assigned = 0, removed = 0 } = 'data' in response ? response.data : response;
+    const { assigned = 0, removed = 0 } = response;
 
     if (updateDocumentCaches && target.id) {
       targets.forEach((docId) => {
@@ -118,7 +112,6 @@ const useBulkDocumentActions = ({
     }
   },
   [
-    api,
     correspondentLookupByName,
     handleCorrespondentCreate,
     resolveTargetDocumentIds,
@@ -141,17 +134,17 @@ const useBulkDocumentActions = ({
         return;
       }
 
-      const normalizedAssignments = assignments.map((entry) => ({
-        correspondent_id: entry.correspondent_id,
-      }));
+    const normalizedAssignments = assignments.map((entry) => ({
+      correspondent_id: entry.correspondent_id,
+    }));
 
-    const response = await api.post<BulkAssignmentResponse>('/documents/bulk/correspondents', {
+    const response: BulkAssignmentResponse = await assignCorrespondentsBulk<BulkAssignmentResponse>({
       document_ids: targets,
       assignments: normalizedAssignments,
       action: 'remove',
     });
 
-    const { assigned = 0, removed = 0 } = 'data' in response ? response.data : response;
+    const { assigned = 0, removed = 0 } = response;
     if (updateDocumentCaches) {
       targets.forEach((docId) => {
         updateDocumentCaches(docId, (doc) => {
@@ -178,12 +171,12 @@ const useBulkDocumentActions = ({
       } else if (assigned > 0) {
         const assignedSuffix = assigned === 1 ? '' : 's';
         setStatusMessage(`Correspondent updated ${assigned} link${assignedSuffix}.`, 'info');
-      } else {
-        setStatusMessage('No correspondents changed.', 'info');
-      }
-    },
-    [api, resolveTargetDocumentIds, setStatusMessage, updateDocumentCaches],
-  );
+    } else {
+      setStatusMessage('No correspondents changed.', 'info');
+    }
+  },
+  [resolveTargetDocumentIds, setStatusMessage, updateDocumentCaches],
+);
 
   const handleDeleteSelection = useCallback(async () => {
     const docIds = Array.isArray(selectedDocumentIds) ? selectedDocumentIds : [];
diff --git a/frontend/src/hooks/documents/useDocumentMutations.ts b/frontend/src/hooks/documents/useDocumentMutations.ts
index 615bd71..7109e29 100644
--- a/frontend/src/hooks/documents/useDocumentMutations.ts
+++ b/frontend/src/hooks/documents/useDocumentMutations.ts
@@ -2,6 +2,17 @@ import { useCallback } from 'react';
 import { isPlainObject } from '../../utils/typeGuards';
 import type { Dispatch, MutableRefObject, SetStateAction } from 'react';
 import { DEFAULT_FOLDER_NAME, getRowId, isDocumentRowKey } from '../../app/appLayoutUtils';
+import {
+  addDocumentTags,
+  createTag,
+  deleteDocumentTag,
+  deleteFolder,
+  moveDocumentsBulk,
+  moveDocumentToFolder,
+  queueDocumentReanalysis,
+  trashDocument,
+  updateDocument,
+} from '../../lib/apiClient';
 
 type DocumentId = string | number;
 type FolderId = DocumentId | 'root';
@@ -35,12 +46,6 @@ type NotifyApiError = (error: unknown, fallbackMessage?: string) => void;
 
 type SetStatusMessage = (message: string, level?: StatusLevel) => void;
 
-interface ApiClient {
-  post<T = unknown>(url: string, data?: unknown, config?: Record<string, unknown>): Promise<{ data: T }>;
-  patch<T = unknown>(url: string, data?: unknown, config?: Record<string, unknown>): Promise<{ data: T }>;
-  delete<T = unknown>(url: string, config?: Record<string, unknown>): Promise<{ data: T }>;
-}
-
 interface Tag {
   id: DocumentId;
   label: string;
@@ -105,7 +110,6 @@ interface FolderDeleteOptions {
 }
 
 interface UseDocumentMutationsArgs {
-  api: ApiClient;
   token?: string | null;
   documentLookup: Map<DocumentId, DocumentLike>;
   folderLabelMap: Map<FolderId, string>;
@@ -181,7 +185,6 @@ const normalizeDocumentId = (value: unknown): DocumentId | null => {
 };
 
 const useDocumentMutations = ({
-  api,
   token,
   documentLookup,
   folderLabelMap,
@@ -286,12 +289,9 @@ const useDocumentMutations = ({
       setLoading(true);
       try {
         if (uniqueIds.length === 1) {
-          await api.patch(`/documents/${uniqueIds[0]}/folder`, { folder_id: target });
+          await moveDocumentToFolder(uniqueIds[0], target);
         } else {
-          await api.post('/documents/bulk/move', {
-            document_ids: uniqueIds,
-            folder_id: target,
-          });
+          await moveDocumentsBulk(uniqueIds, target);
         }
 
         const count = uniqueIds.length;
@@ -382,7 +382,6 @@ const useDocumentMutations = ({
       }
     },
     [
-      api,
       documentLookup,
       folderLabelMap,
       ensureFolderData,
@@ -413,9 +412,7 @@ const useDocumentMutations = ({
       }
       setLoading(true);
       try {
-        await api.post(`/documents/${documentId}/assets`, null, {
-          params: { force: true },
-        });
+        await queueDocumentReanalysis(documentId, { force: true });
         setStatusMessage('Document re-analysis queued.', 'info');
         await refreshCurrentFolder();
       } catch (error) {
@@ -425,7 +422,7 @@ const useDocumentMutations = ({
         setLoading(false);
       }
     },
-    [api, token, refreshCurrentFolder, notifyApiError, setStatusMessage, setLoading],
+    [token, refreshCurrentFolder, notifyApiError, setStatusMessage, setLoading],
   );
 
   const handleDocumentsDelete = useCallback(
@@ -444,7 +441,7 @@ const useDocumentMutations = ({
       }
 
       try {
-        await Promise.all(documentIds.map((documentId) => api.post(`/documents/${documentId}/trash`)));
+        await Promise.all(documentIds.map((documentId) => trashDocument(documentId)));
 
         removeDocumentsFromCaches(documentIds);
 
@@ -468,7 +465,6 @@ const useDocumentMutations = ({
       }
     },
     [
-      api,
       token,
       removeDocumentsFromCaches,
       previewDocumentId,
@@ -489,7 +485,7 @@ const useDocumentMutations = ({
 
       setLoading(true);
       try {
-        const { data } = await api.patch(`/documents/${documentId}`, { title: trimmed });
+        const data = await updateDocument(documentId, { title: trimmed });
         const updatedDocument = extractDocumentFromResponse?.(data);
 
         if (updatedDocument && ingestDocuments) {
@@ -514,7 +510,6 @@ const useDocumentMutations = ({
       }
     },
     [
-      api,
       extractDocumentFromResponse,
       ingestDocuments,
       notifyApiError,
@@ -529,7 +524,7 @@ const useDocumentMutations = ({
       setLoading(true);
       const payload = { issued_at: nextIssuedDate || null };
       try {
-        const { data } = await api.patch(`/documents/${documentId}`, payload);
+        const data = await updateDocument(documentId, payload);
         const updatedDocument = extractDocumentFromResponse?.(data);
 
         if (updatedDocument && ingestDocuments) {
@@ -555,7 +550,6 @@ const useDocumentMutations = ({
       }
     },
     [
-      api,
       extractDocumentFromResponse,
       ingestDocuments,
       notifyApiError,
@@ -584,7 +578,7 @@ const useDocumentMutations = ({
       };
 
       try {
-        await api.post(`/documents/${documentId}/tags`, { tag_ids: [cachedTag.id] });
+        await addDocumentTags(documentId, [cachedTag.id]);
         updateDocumentCaches(documentId, (doc) => {
           if (!doc) {
             return doc;
@@ -603,7 +597,7 @@ const useDocumentMutations = ({
         return false;
       }
     },
-    [api, notifyApiError, setStatusMessage, updateDocumentCaches],
+    [notifyApiError, setStatusMessage, updateDocumentCaches],
   );
 
   const handleDocumentTagAdd = useCallback(
@@ -621,8 +615,8 @@ const useDocumentMutations = ({
       }
       try {
         if (!tag) {
-          const payload = tagManager.buildPayload({ label: normalizedLabel });
-          const { data } = await api.post('/tags', payload);
+          const payload = tagManager.buildPayload({ label: normalizedLabel }) as { label: string; color?: string | null };
+          const data = await createTag(payload);
           tag = data as Tag;
           await refreshTags();
         }
@@ -637,7 +631,7 @@ const useDocumentMutations = ({
         notifyApiError(error, 'Failed to assign tag.');
       }
     },
-    [api, tags, refreshTags, attachTagToDocument, notifyApiError, tagManager],
+    [tags, refreshTags, attachTagToDocument, notifyApiError, tagManager],
   );
 
   const handleDocumentTagAttach = useCallback(
@@ -706,7 +700,7 @@ const useDocumentMutations = ({
       }
 
       try {
-        await api.delete(`/documents/${documentId}/tags/${tagId}`);
+        await deleteDocumentTag(documentId, tagId);
         applyTagRemovalToCaches(documentId, tagId);
         if (refreshTagList) {
           await refreshTags();
@@ -721,7 +715,7 @@ const useDocumentMutations = ({
         return false;
       }
     },
-    [api, applyTagRemovalToCaches, notifyApiError, refreshTags, setStatusMessage],
+    [applyTagRemovalToCaches, notifyApiError, refreshTags, setStatusMessage],
   );
 
   const handleFolderDelete = useCallback(
@@ -757,7 +751,7 @@ const useDocumentMutations = ({
           return false;
         }
 
-        await api.delete(`/folders/${folderId}`);
+        await deleteFolder(folderId);
 
         setFolderNodes((prev: Map<FolderId, FolderNode>) => {
           const next = new Map<FolderId, FolderNode>(prev);
@@ -815,7 +809,6 @@ const useDocumentMutations = ({
       }
     },
     [
-      api,
       token,
       ensureFolderData,
       selectedFolder,
diff --git a/frontend/src/hooks/documents/useDocumentsWorkspace.ts b/frontend/src/hooks/documents/useDocumentsWorkspace.ts
index 66eebed..9db8f63 100644
--- a/frontend/src/hooks/documents/useDocumentsWorkspace.ts
+++ b/frontend/src/hooks/documents/useDocumentsWorkspace.ts
@@ -566,7 +566,6 @@ const useDocumentsWorkspace = ({
     registerPasskey,
     revokePasskey,
   } = usePasskeys({
-    api,
     notifyApiError,
     setStatusMessage,
     token,
@@ -815,7 +814,6 @@ const useDocumentsWorkspace = ({
     handleDocumentIssuedUpdate,
     handleTagRemove,
   } = useDocumentMutations({
-    api,
     token,
     documentLookup,
     folderLabelMap,
@@ -861,7 +859,6 @@ const useDocumentsWorkspace = ({
     handleFolderDelete,
     folderClickHandlers,
   } = useFolderTreeActions({
-    api,
     token,
     folderNodes,
     setFolderNodes,
@@ -996,7 +993,6 @@ const useDocumentsWorkspace = ({
     handleBulkCorrespondentRemove,
     handleDeleteSelection,
   } = useBulkDocumentActions({
-    api,
     resolveTargetDocumentIds,
     correspondentLookupByName,
     handleCorrespondentCreate,
diff --git a/frontend/src/hooks/documents/useFolderTreeActions.ts b/frontend/src/hooks/documents/useFolderTreeActions.ts
index 40d0bf0..2d27265 100644
--- a/frontend/src/hooks/documents/useFolderTreeActions.ts
+++ b/frontend/src/hooks/documents/useFolderTreeActions.ts
@@ -1,6 +1,12 @@
 import { useCallback, useMemo } from 'react';
 import type { DragEvent } from 'react';
 import { DEFAULT_FOLDER_NAME, hasFiles } from '../../app/appLayoutUtils';
+import {
+  createFolder,
+  deleteFolder,
+  moveFolder as moveFolderRequest,
+  renameFolder as renameFolderRequest,
+} from '../../lib/apiClient';
 
 type FolderId = string | number;
 type FolderKey = FolderId | 'root';
@@ -22,12 +28,6 @@ interface FolderContentsState {
   [key: string]: unknown;
 }
 
-interface ApiClient {
-  patch: (url: string, data?: unknown) => Promise<any>;
-  post: (url: string, data?: unknown) => Promise<{ data: any }>;
-  delete: (url: string) => Promise<any>;
-}
-
 interface EnsureFolderOptions {
   force?: boolean;
   includeDocuments?: boolean;
@@ -53,7 +53,6 @@ interface FolderClickHandlers {
 }
 
 interface UseFolderTreeActionsOptions {
-  api: ApiClient;
   token?: string | null;
   folderNodes: Map<FolderKey, FolderNode>;
   setFolderNodes: (updater: (prev: Map<FolderKey, FolderNode>) => Map<FolderKey, FolderNode>) => void;
@@ -84,7 +83,6 @@ interface UseFolderTreeActionsOptions {
 }
 
 const useFolderTreeActions = ({
-  api,
   token,
   folderNodes,
   setFolderNodes,
@@ -129,7 +127,7 @@ const useFolderTreeActions = ({
       const parent_id = targetKey === 'root' ? null : targetKey;
 
       try {
-        await api.patch(`/folders/${folderId}`, { parent_id });
+        await moveFolderRequest(folderId, parent_id);
 
         setFolderNodes((prev) => {
           const next = new Map(prev);
@@ -202,7 +200,6 @@ const useFolderTreeActions = ({
       }
     },
     [
-      api,
       ensureFolderData,
       folderNodes,
       notifyApiError,
@@ -295,7 +292,7 @@ const useFolderTreeActions = ({
 
       setLoading(true);
       try {
-        await api.patch(`/folders/${folderId}`, { name: trimmed });
+        await renameFolderRequest(folderId, trimmed);
 
         setFolderNodes((prev) => {
           const next = new Map(prev);
@@ -331,7 +328,6 @@ const useFolderTreeActions = ({
       }
     },
     [
-      api,
       notifyApiError,
       setCurrentFolder,
       setFolderContents,
@@ -359,33 +355,37 @@ const useFolderTreeActions = ({
       setCreatingFolder(true);
       let succeeded = false;
       try {
-        const { data } = await api.post('/folders', payload);
+        const data = await createFolder(payload);
+        const folderData = (data as { folder?: { id?: FolderKey; name?: string; parent_id?: FolderKey | null; children?: FolderKey[] } }).folder;
+        if (!folderData?.id) {
+          throw new Error('Folder creation failed.');
+        }
         setStatusMessage('Folder created.', 'success');
         setFolderNodes((prev) => {
           const next = new Map(prev);
-          const parentId = payload.parent_id || 'root';
+          const parentId = folderData.parent_id ?? payload.parent_id ?? 'root';
           const parentNode = next.get(parentId);
           if (parentNode) {
             next.set(parentId, {
               ...parentNode,
-              children: parentNode.children.concat([data.folder.id]),
+              children: parentNode.children.concat([folderData.id]),
               loaded: true,
               hasChildren: true,
             });
           }
-          next.set(data.folder.id, {
-            id: data.folder.id,
-            name: data.folder.name,
+          next.set(folderData.id, {
+            id: folderData.id,
+            name: folderData.name ?? payload.name,
             parentId: parentId,
-            children: [],
+            children: folderData.children || [],
             expanded: false,
             loaded: false,
-            hasChildren: false,
+            hasChildren: Array.isArray(folderData.children) ? folderData.children.length > 0 : false,
           });
           return next;
         });
         await ensureFolderData(selectedFolder, { force: true, prefetchDepth: 1 });
-        await selectFolder(data.folder.id, { immediate: true });
+        await selectFolder(folderData.id, { immediate: true });
         succeeded = true;
         return true;
       } catch (error) {
@@ -400,7 +400,6 @@ const useFolderTreeActions = ({
       }
     },
     [
-      api,
       ensureFolderData,
       notifyApiError,
       selectFolder,
@@ -445,7 +444,7 @@ const useFolderTreeActions = ({
           return false;
         }
 
-        await api.delete(`/folders/${folderId}`);
+        await deleteFolder(folderId);
 
         setFolderNodes((prev) => {
           const next = new Map(prev);
@@ -503,7 +502,6 @@ const useFolderTreeActions = ({
       }
     },
     [
-      api,
       token,
       applySelectedFolder,
       ensureFolderData,
diff --git a/frontend/src/lib/apiClient.ts b/frontend/src/lib/apiClient.ts
index 0ffbac9..66115a0 100644
--- a/frontend/src/lib/apiClient.ts
+++ b/frontend/src/lib/apiClient.ts
@@ -9,6 +9,8 @@ import type {
   FolderTreeNode,
   Identifier,
   PasskeySummary,
+  TenantSnippet,
+  TagResponse,
 } from './apiTypes';
 
 const normalizeNumber = (value: unknown): number | undefined => {
@@ -75,6 +77,176 @@ export const listPasskeys = async (): Promise<PasskeySummary[]> => {
   return Array.isArray(data) ? data : [];
 };
 
+export const moveDocumentsBulk = async (documentIds: Identifier[], folderId: Identifier | null): Promise<void> => {
+  await api.post('/documents/bulk/move', {
+    document_ids: documentIds,
+    folder_id: folderId,
+  });
+};
+
+export const queueDocumentReanalysis = async (
+  documentId: Identifier,
+  options: { force?: boolean } = {},
+): Promise<void> => {
+  const { force = false } = options;
+  await api.post(`/documents/${documentId}/assets`, null, { params: { force } });
+};
+
+export const trashDocument = async (documentId: Identifier): Promise<void> => {
+  await api.post(`/documents/${documentId}/trash`);
+};
+
+export const addDocumentTags = async (documentId: Identifier, tagIds: Identifier[]): Promise<void> => {
+  await api.post(`/documents/${documentId}/tags`, { tag_ids: tagIds });
+};
+
+export const createTag = async (payload: { label: string; color?: string | null }): Promise<TagResponse> => {
+  const { data } = await api.post<TagResponse>('/tags', payload);
+  return data;
+};
+
+export const createFolder = async (payload: { name: string; parent_id?: Identifier | null }): Promise<unknown> => {
+  const { data } = await api.post('/folders', payload);
+  return data;
+};
+
+export const assignCorrespondentsBulk = async <T = unknown>(
+  payload: Record<string, unknown>,
+): Promise<T> => {
+  const { data } = await api.post<T>('/documents/bulk/correspondents', payload);
+  return data;
+};
+
+export const createApiToken = async (payload: {
+  capability_set_id: Identifier;
+  label?: string;
+  expires_at?: string;
+}): Promise<{ token_info?: ApiTokenRecord; token?: string }> => {
+  const { data } = await api.post('/profile/api-tokens', payload);
+  return data as { token_info?: ApiTokenRecord; token?: string };
+};
+
+export const regenerateApiToken = async (
+  tokenId: Identifier,
+): Promise<{ token_info?: ApiTokenRecord; token?: string }> => {
+  const { data } = await api.post(`/profile/api-tokens/${tokenId}/regenerate`);
+  return data as { token_info?: ApiTokenRecord; token?: string };
+};
+
+export const startPasskeyRegistration = async (): Promise<unknown> => {
+  const { data } = await api.post('/auth/passkeys/register/start', {});
+  return data;
+};
+
+export const finishPasskeyRegistration = async (payload: unknown): Promise<unknown> => {
+  const { data } = await api.post('/auth/passkeys/register/finish', payload);
+  return data;
+};
+
+export const startPasskeyLogin = async (username: string): Promise<unknown> => {
+  const { data } = await api.post('/auth/passkeys/login/start', { username });
+  return data;
+};
+
+export const finishPasskeyLogin = async (payload: unknown): Promise<unknown> => {
+  const { data } = await api.post('/auth/passkeys/login/finish', payload);
+  return data;
+};
+
+export const performLogin = async (payload: Record<string, unknown>): Promise<unknown> => {
+  const { data } = await api.post('/auth/login', payload);
+  return data;
+};
+
+export const selectTenant = async (
+  payload: { tenant_id: Identifier },
+  selectionToken: string,
+): Promise<unknown> => {
+  const { data } = await api.post('/auth/select-tenant', payload, {
+    headers: {
+      Authorization: `Bearer ${selectionToken}`,
+    },
+  });
+  return data;
+};
+
+export const startSignup = async (username: string): Promise<unknown> => {
+  const { data } = await api.post('/auth/signup/start', { username });
+  return data;
+};
+
+export const finishSignup = async (payload: unknown): Promise<unknown> => {
+  const { data } = await api.post('/auth/signup/finish', payload);
+  return data;
+};
+
+export const updateDocument = async (
+  id: Identifier,
+  payload: Record<string, unknown>,
+): Promise<DocumentResponse> => {
+  const { data } = await api.patch<DocumentResponse>(`/documents/${id}`, payload);
+  return data;
+};
+
+export const moveDocumentToFolder = async (id: Identifier, folderId: Identifier | null): Promise<void> => {
+  await api.patch(`/documents/${id}/folder`, { folder_id: folderId });
+};
+
+export const deleteDocumentTag = async (documentId: Identifier, tagId: Identifier): Promise<void> => {
+  await api.delete(`/documents/${documentId}/tags/${tagId}`);
+};
+
+export const deleteFolder = async (folderId: Identifier): Promise<void> => {
+  await api.delete(`/folders/${folderId}`);
+};
+
+export const moveFolder = async (folderId: Identifier, parentId: Identifier | null): Promise<void> => {
+  await api.patch(`/folders/${folderId}`, { parent_id: parentId });
+};
+
+export const renameFolder = async (folderId: Identifier, name: string): Promise<void> => {
+  await api.patch(`/folders/${folderId}`, { name });
+};
+
+export const createCapabilitySet = async (
+  payload: { slug?: string; label?: string; capabilities: string[] },
+): Promise<CapabilitySetResponse & { label?: string }> => {
+  const { data } = await api.post<CapabilitySetResponse & { label?: string }>('/capability-sets', payload);
+  return data;
+};
+
+export const updateCapabilitySet = async (
+  id: Identifier,
+  payload: { slug?: string; label?: string; capabilities?: string[] },
+): Promise<CapabilitySetResponse & { label?: string }> => {
+  const { data } = await api.patch<CapabilitySetResponse & { label?: string }>(`/capability-sets/${id}`, payload);
+  return data;
+};
+
+export const deleteCapabilitySet = async (id: Identifier): Promise<void> => {
+  await api.delete(`/capability-sets/${id}`);
+};
+
+export const deleteApiToken = async (tokenId: Identifier): Promise<void> => {
+  await api.delete(`/profile/api-tokens/${tokenId}`);
+};
+
+export const deletePasskey = async (
+  passkeyId: Identifier,
+  options: { reason?: string } = {},
+): Promise<void> => {
+  const query = options.reason ? `?reason=${encodeURIComponent(options.reason)}` : '';
+  await api.delete(`/profile/passkeys/${passkeyId}${query}`);
+};
+
+export const listTenants = async (): Promise<TenantSnippet[]> => {
+  const { data } = await api.get<{ tenants?: TenantSnippet[] } | TenantSnippet[]>('/tenants');
+  if (Array.isArray(data)) {
+    return data;
+  }
+  return Array.isArray(data?.tenants) ? data.tenants : [];
+};
+
 export type {
   DownloadLink,
   DocumentResponse,
@@ -85,4 +257,5 @@ export type {
   ApiTokenRecord,
   PasskeySummary,
   Identifier,
+  TenantSnippet,
 } from './apiTypes';
diff --git a/frontend/src/settings/useApiTokens.ts b/frontend/src/settings/useApiTokens.ts
index c889fa5..23b234c 100644
--- a/frontend/src/settings/useApiTokens.ts
+++ b/frontend/src/settings/useApiTokens.ts
@@ -1,14 +1,11 @@
 import { useCallback, useState } from 'react';
-
-interface ApiTokenRecord {
-  id?: string | number;
-  label?: string;
-  expires_at?: string;
-  created_at?: string;
-  last_used_at?: string;
-  capability_set_id?: string | number;
-  [key: string]: unknown;
-}
+import {
+  createApiToken,
+  deleteApiToken,
+  listApiTokens,
+  regenerateApiToken,
+  type ApiTokenRecord,
+} from '../lib/apiClient';
 
 interface ApiTokensResponse {
   token_info?: ApiTokenRecord;
@@ -22,11 +19,6 @@ interface CreateTokenArgs {
 }
 
 interface UseApiTokensArgs {
-  api: {
-    get: <T = unknown>(url: string) => Promise<{ data: T }>;
-    post: <T = unknown>(url: string, payload?: unknown) => Promise<{ data: T }>;
-    delete: (url: string) => Promise<unknown>;
-  };
   notifyApiError?: (error: unknown, message: string) => void;
   setStatusMessage?: (message: string, variant?: string) => void;
   token?: string | null;
@@ -46,7 +38,7 @@ interface UseApiTokensResult {
   dismissSecret: () => void;
 }
 
-const useApiTokens = ({ api, notifyApiError, setStatusMessage, token }: UseApiTokensArgs): UseApiTokensResult => {
+const useApiTokens = ({ notifyApiError, setStatusMessage, token }: UseApiTokensArgs): UseApiTokensResult => {
   const [tokens, setTokens] = useState<ApiTokenRecord[]>([]);
   const [loading, setLoading] = useState(false);
   const [creating, setCreating] = useState(false);
@@ -60,14 +52,14 @@ const useApiTokens = ({ api, notifyApiError, setStatusMessage, token }: UseApiTo
     }
     setLoading(true);
     try {
-      const { data } = await api.get<ApiTokenRecord[]>('/profile/api-tokens');
+      const data = await listApiTokens();
       setTokens(Array.isArray(data) ? data : []);
     } catch (error) {
       notifyApiError?.(error, 'Failed to load API tokens.');
     } finally {
       setLoading(false);
     }
-  }, [api, notifyApiError, token]);
+  }, [notifyApiError, token]);
 
   const create = useCallback(
     async ({ label, expires_at, capability_set_id }: CreateTokenArgs = {}) => {
@@ -76,7 +68,7 @@ const useApiTokens = ({ api, notifyApiError, setStatusMessage, token }: UseApiTo
       }
       setCreating(true);
       try {
-        const payload: Record<string, unknown> = { capability_set_id };
+        const payload: { capability_set_id: string | number; label?: string; expires_at?: string } = { capability_set_id };
         if (label) {
           payload.label = label;
         }
@@ -84,7 +76,7 @@ const useApiTokens = ({ api, notifyApiError, setStatusMessage, token }: UseApiTo
           payload.expires_at = expires_at;
         }
 
-        const { data } = await api.post<ApiTokensResponse>('/profile/api-tokens', payload);
+        const data = await createApiToken(payload) as ApiTokensResponse;
         if (data?.token_info) {
           setTokens((previous) => {
             const filtered = previous.filter((entry) => entry.id !== data.token_info?.id);
@@ -107,7 +99,7 @@ const useApiTokens = ({ api, notifyApiError, setStatusMessage, token }: UseApiTo
         setCreating(false);
       }
     },
-    [api, creating, notifyApiError, refresh, setStatusMessage],
+    [creating, notifyApiError, refresh, setStatusMessage],
   );
 
   const revoke = useCallback(
@@ -117,7 +109,7 @@ const useApiTokens = ({ api, notifyApiError, setStatusMessage, token }: UseApiTo
       }
       setDeletingId(tokenId);
       try {
-        await api.delete(`/profile/api-tokens/${tokenId}`);
+        await deleteApiToken(tokenId);
         await refresh();
         setStatusMessage?.('API token revoked.', 'success');
         return true;
@@ -128,7 +120,7 @@ const useApiTokens = ({ api, notifyApiError, setStatusMessage, token }: UseApiTo
         setDeletingId(null);
       }
     },
-    [api, notifyApiError, refresh, setStatusMessage],
+    [notifyApiError, refresh, setStatusMessage],
   );
 
   const regenerate = useCallback(
@@ -138,7 +130,7 @@ const useApiTokens = ({ api, notifyApiError, setStatusMessage, token }: UseApiTo
       }
       setRegeneratingId(tokenId);
       try {
-        const { data } = await api.post<ApiTokensResponse>(`/profile/api-tokens/${tokenId}/regenerate`);
+        const data = await regenerateApiToken(tokenId) as ApiTokensResponse;
         if (data?.token_info) {
           setTokens((previous) => {
             let found = false;
@@ -171,7 +163,7 @@ const useApiTokens = ({ api, notifyApiError, setStatusMessage, token }: UseApiTo
         setRegeneratingId(null);
       }
     },
-    [api, notifyApiError, refresh, setStatusMessage],
+    [notifyApiError, refresh, setStatusMessage],
   );
 
   const dismissSecret = useCallback(() => {
diff --git a/frontend/src/settings/useCapabilitySets.ts b/frontend/src/settings/useCapabilitySets.ts
index cb13509..5bef981 100644
--- a/frontend/src/settings/useCapabilitySets.ts
+++ b/frontend/src/settings/useCapabilitySets.ts
@@ -1,5 +1,10 @@
 import { useCallback, useEffect, useState } from 'react';
-import { listCapabilitySets } from '../lib/apiClient';
+import {
+  createCapabilitySet as createCapabilitySetRequest,
+  deleteCapabilitySet as deleteCapabilitySetRequest,
+  listCapabilitySets,
+  updateCapabilitySet as updateCapabilitySetRequest,
+} from '../lib/apiClient';
 
 type Identifier = string | number;
 
@@ -11,21 +16,13 @@ interface CapabilitySet {
   [key: string]: unknown;
 }
 
-interface ApiClient {
-  get<T = CapabilitySet[]>(path: string): Promise<{ data: T }>;
-  post<T = CapabilitySet>(path: string, payload?: unknown): Promise<{ data: T }>;
-  patch<T = CapabilitySet>(path: string, payload?: unknown): Promise<{ data: T }>;
-  delete: (path: string) => Promise<void>;
-}
-
 interface UseCapabilitySetsOptions {
-  api: ApiClient;
   notifyApiError?: (error: unknown, message: string) => void;
   setStatusMessage?: (message: string, level?: string) => void;
   token?: string | null;
 }
 
-const useCapabilitySets = ({ api, notifyApiError, setStatusMessage, token }: UseCapabilitySetsOptions) => {
+const useCapabilitySets = ({ notifyApiError, setStatusMessage, token }: UseCapabilitySetsOptions) => {
   const [capabilitySets, setCapabilitySets] = useState<CapabilitySet[]>([]);
   const [capabilitySetsLoading, setCapabilitySetsLoading] = useState(false);
   const [creatingCapabilitySet, setCreatingCapabilitySet] = useState(false);
@@ -92,7 +89,7 @@ const useCapabilitySets = ({ api, notifyApiError, setStatusMessage, token }: Use
           payload.label = trimmedLabel;
         }
 
-        const { data } = await api.post<CapabilitySet>('/capability-sets', payload);
+        const data = await createCapabilitySetRequest(payload);
         if (data) {
           applyCapabilitySets((previous) => {
             const next = previous.filter((entry) => entry?.id !== data.id);
@@ -113,7 +110,6 @@ const useCapabilitySets = ({ api, notifyApiError, setStatusMessage, token }: Use
       }
     },
     [
-      api,
       applyCapabilitySets,
       creatingCapabilitySet,
       notifyApiError,
@@ -154,7 +150,7 @@ const useCapabilitySets = ({ api, notifyApiError, setStatusMessage, token }: Use
           payload.capabilities = capabilities;
         }
 
-        const { data } = await api.patch<CapabilitySet>(`/capability-sets/${capabilitySetId}`, payload);
+        const data = await updateCapabilitySetRequest(capabilitySetId, payload);
         if (data) {
           applyCapabilitySets((previous) => {
             let found = false;
@@ -184,7 +180,6 @@ const useCapabilitySets = ({ api, notifyApiError, setStatusMessage, token }: Use
       }
     },
     [
-      api,
       applyCapabilitySets,
       notifyApiError,
       refreshCapabilitySets,
@@ -200,7 +195,7 @@ const useCapabilitySets = ({ api, notifyApiError, setStatusMessage, token }: Use
       }
       setDeletingCapabilitySetId(capabilitySetId);
       try {
-        await api.delete(`/capability-sets/${capabilitySetId}`);
+        await deleteCapabilitySetRequest(capabilitySetId);
         applyCapabilitySets((previous) => previous.filter((entry) => entry?.id !== capabilitySetId));
         setStatusMessage?.('Capability set deleted.', 'success');
         return true;
@@ -211,7 +206,7 @@ const useCapabilitySets = ({ api, notifyApiError, setStatusMessage, token }: Use
         setDeletingCapabilitySetId(null);
       }
     },
-    [api, applyCapabilitySets, notifyApiError, setStatusMessage],
+    [applyCapabilitySets, notifyApiError, setStatusMessage],
   );
 
   return {
diff --git a/frontend/src/settings/usePasskeys.ts b/frontend/src/settings/usePasskeys.ts
index 9e891a0..18d0821 100644
--- a/frontend/src/settings/usePasskeys.ts
+++ b/frontend/src/settings/usePasskeys.ts
@@ -6,12 +6,12 @@ import {
   preparePublicKeyCreationOptions,
   serializeRegistrationCredential,
 } from '../utils/webauthn';
-
-type ApiClient = {
-  get: (path: string) => Promise<{ data: unknown }>;
-  post: (path: string, body?: unknown) => Promise<{ data: unknown }>;
-  delete: (path: string) => Promise<{ data: unknown }>;
-};
+import {
+  deletePasskey,
+  finishPasskeyRegistration,
+  listPasskeys,
+  startPasskeyRegistration,
+} from '../lib/apiClient';
 
 type StatusMessageFn = (message: string, variant?: string) => void;
 type NotifyApiErrorFn = (error: unknown, message: string) => void;
@@ -69,7 +69,6 @@ export type RevokePasskeyResult =
   | { ok: false; reason: RevokePasskeyFailureReason; message?: string };
 
 interface UsePasskeysArgs {
-  api: ApiClient;
   notifyApiError: NotifyApiErrorFn;
   setStatusMessage: StatusMessageFn;
   token?: string | null;
@@ -89,7 +88,7 @@ interface UsePasskeysResult {
   ) => Promise<RevokePasskeyResult>;
 }
 
-const usePasskeys = ({ api, notifyApiError, setStatusMessage, token }: UsePasskeysArgs): UsePasskeysResult => {
+const usePasskeys = ({ notifyApiError, setStatusMessage, token }: UsePasskeysArgs): UsePasskeysResult => {
   const [passkeys, setPasskeys] = useState<PasskeyRecord[]>([]);
   const [passkeysSupported, setPasskeysSupported] = useState<boolean | null>(null);
   const [passkeysLoading, setPasskeysLoading] = useState(false);
@@ -102,8 +101,7 @@ const usePasskeys = ({ api, notifyApiError, setStatusMessage, token }: UsePasske
     }
     setPasskeysLoading(true);
     try {
-      const { data } = await api.get('/profile/passkeys');
-      const passkeyData = Array.isArray(data) ? (data as PasskeyRecord[]) : [];
+      const passkeyData = await listPasskeys();
       setPasskeys(passkeyData);
       setPasskeysSupported(true);
     } catch (error) {
@@ -117,7 +115,7 @@ const usePasskeys = ({ api, notifyApiError, setStatusMessage, token }: UsePasske
     } finally {
       setPasskeysLoading(false);
     }
-  }, [api, notifyApiError, token]);
+  }, [notifyApiError, token]);
 
   const registerPasskey = useCallback(
     async ({ nickname }: { nickname?: string } = {}): Promise<RegisterPasskeyResult> => {
@@ -132,7 +130,7 @@ const usePasskeys = ({ api, notifyApiError, setStatusMessage, token }: UsePasske
 
       setRegisteringPasskey(true);
       try {
-        const { data } = await api.post('/auth/passkeys/register/start', {});
+        const data = await startPasskeyRegistration();
         const challengeData = data as PasskeyChallengeResponse | undefined;
         const challengeId = challengeData?.challengeId || challengeData?.challenge_id;
         const publicKeyOptions =
@@ -164,7 +162,7 @@ const usePasskeys = ({ api, notifyApiError, setStatusMessage, token }: UsePasske
           payload.nickname = trimmedNickname;
         }
 
-        await api.post('/auth/passkeys/register/finish', payload);
+        await finishPasskeyRegistration(payload);
         await refreshPasskeys();
         setPasskeysSupported(true);
         setStatusMessage('Passkey registered.', 'success');
@@ -188,7 +186,7 @@ const usePasskeys = ({ api, notifyApiError, setStatusMessage, token }: UsePasske
         setRegisteringPasskey(false);
       }
     },
-    [api, notifyApiError, refreshPasskeys, registeringPasskey, setStatusMessage],
+    [notifyApiError, refreshPasskeys, registeringPasskey, setStatusMessage],
   );
 
   const revokePasskey = useCallback(
@@ -201,8 +199,7 @@ const usePasskeys = ({ api, notifyApiError, setStatusMessage, token }: UsePasske
       }
       setRevokingPasskeyId(passkeyId);
       try {
-        const query = reason ? `?reason=${encodeURIComponent(reason)}` : '';
-        await api.delete(`/profile/passkeys/${passkeyId}${query}`);
+        await deletePasskey(passkeyId, { reason });
         await refreshPasskeys();
         setStatusMessage('Passkey revoked.', 'success');
         return { ok: true };
@@ -214,7 +211,7 @@ const usePasskeys = ({ api, notifyApiError, setStatusMessage, token }: UsePasske
         setRevokingPasskeyId(null);
       }
     },
-    [api, notifyApiError, refreshPasskeys, setStatusMessage],
+    [notifyApiError, refreshPasskeys, setStatusMessage],
   );
 
   return {