diff --git a/web/src/types/api.d.ts b/web/src/types/api.d.ts
index 5264f28..fc1b4a8 100644
--- a/web/src/types/api.d.ts
+++ b/web/src/types/api.d.ts
@@ -97,6 +97,31 @@ export interface BookInfo {
     cover_image_path: string;
 }
 
+// Dashboard type definitions
+// CRITICAL: Must match Go handler return types EXACTLY
+// Source: handlers.SectionData in collections.go (lines 73-81)
+// Used in: dashboard API responses, TypeScript dashboard components
+export interface SectionData {
+    id: string;
+    is_system: boolean;
+    title: string;
+    description: string;
+    icon: string;
+    items: BookInfo[];
+    view_all_url: string;
+    priority: number;
+}
+
+// Matches database.UserDashboardPreferences and dashboard preferences API
+// Source: internal/database/models.go:381-390
+// Used in: dashboard preferences API
+export interface DashboardPreferences {
+    library_id: string;
+    hidden_collections: string[];
+    collection_order: string[];
+    items_per_section: number;
+}
+
 // Matches handlers.UnlinkedBookData JSON response
 // Used in: unlinked_books.ts, unlinked_books.templ
 export interface UnlinkedBookData {