diff --git a/lib/data/api/knowledge_api.dart b/lib/data/api/knowledge_api.dart
new file mode 100644
index 0000000..71e84f7
--- /dev/null
+++ b/lib/data/api/knowledge_api.dart
@@ -0,0 +1,86 @@
+import 'package:dio/dio.dart';
+
+import '../models/knowledge_item.dart';
+import 'api_client.dart';
+
+class KnowledgeApi {
+  final Dio _dio;
+  const KnowledgeApi(this._dio);
+
+  /// Fetch a page of IDs. Returns (ids, total).
+  Future<(List<int>, int)> fetchIds({
+    String? noteType,
+    List<String> tags = const [],
+    String sort = 'modified',
+    String? q,
+    int limit = 50,
+    int offset = 0,
+  }) async {
+    try {
+      final params = <String, dynamic>{
+        'limit': limit,
+        'offset': offset,
+        'sort': sort,
+        if (noteType != null) 'type': noteType,
+        if (tags.isNotEmpty) 'tags': tags.join(','),
+        if (q != null && q.isNotEmpty) 'q': q,
+      };
+      final response =
+          await _dio.get('/api/knowledge/ids', queryParameters: params);
+      final data = response.data as Map<String, dynamic>;
+      final ids =
+          (data['ids'] as List<dynamic>).map((e) => e as int).toList();
+      final total = data['total'] as int;
+      return (ids, total);
+    } on DioException catch (e) {
+      throw dioToApp(e);
+    }
+  }
+
+  /// Batch-hydrate up to 100 IDs into full items.
+  Future<List<KnowledgeItem>> fetchBatch(List<int> ids) async {
+    if (ids.isEmpty) return [];
+    try {
+      final response = await _dio.get(
+        '/api/knowledge/batch',
+        queryParameters: {'ids': ids.join(',')},
+      );
+      final data = response.data as Map<String, dynamic>;
+      return (data['items'] as List<dynamic>)
+          .map((e) => KnowledgeItem.fromJson(e as Map<String, dynamic>))
+          .toList();
+    } on DioException catch (e) {
+      throw dioToApp(e);
+    }
+  }
+
+  /// Per-type counts for tab labels.
+  Future<Map<String, int>> fetchCounts({List<String> tags = const []}) async {
+    try {
+      final params = <String, dynamic>{
+        if (tags.isNotEmpty) 'tags': tags.join(','),
+      };
+      final response = await _dio.get('/api/knowledge/counts',
+          queryParameters: params);
+      return (response.data as Map<String, dynamic>)
+          .map((k, v) => MapEntry(k, (v as num).toInt()));
+    } on DioException catch (e) {
+      throw dioToApp(e);
+    }
+  }
+
+  /// All tags for the current type filter.
+  Future<List<String>> fetchTags({String? noteType}) async {
+    try {
+      final response = await _dio.get(
+        '/api/knowledge/tags',
+        queryParameters: {if (noteType != null) 'type': noteType},
+      );
+      return (response.data['tags'] as List<dynamic>)
+          .map((e) => e as String)
+          .toList();
+    } on DioException catch (e) {
+      throw dioToApp(e);
+    }
+  }
+}
diff --git a/lib/data/repositories/knowledge_repository.dart b/lib/data/repositories/knowledge_repository.dart
new file mode 100644
index 0000000..f6264ac
--- /dev/null
+++ b/lib/data/repositories/knowledge_repository.dart
@@ -0,0 +1,33 @@
+import '../api/knowledge_api.dart';
+import '../models/knowledge_item.dart';
+
+class KnowledgeRepository {
+  final KnowledgeApi _api;
+  const KnowledgeRepository(this._api);
+
+  Future<(List<int>, int)> fetchIds({
+    String? noteType,
+    List<String> tags = const [],
+    String sort = 'modified',
+    String? q,
+    int limit = 50,
+    int offset = 0,
+  }) =>
+      _api.fetchIds(
+        noteType: noteType,
+        tags: tags,
+        sort: sort,
+        q: q,
+        limit: limit,
+        offset: offset,
+      );
+
+  Future<List<KnowledgeItem>> fetchBatch(List<int> ids) =>
+      _api.fetchBatch(ids);
+
+  Future<Map<String, int>> fetchCounts({List<String> tags = const []}) =>
+      _api.fetchCounts(tags: tags);
+
+  Future<List<String>> fetchTags({String? noteType}) =>
+      _api.fetchTags(noteType: noteType);
+}
diff --git a/lib/providers/api_client_provider.dart b/lib/providers/api_client_provider.dart
index 2aba0ce..7ae55e2 100644
--- a/lib/providers/api_client_provider.dart
+++ b/lib/providers/api_client_provider.dart
@@ -6,6 +6,7 @@ import '../data/api/api_client.dart';
 import '../data/api/auth_api.dart';
 import '../data/api/briefing_api.dart';
 import '../data/api/chat_api.dart';
+import '../data/api/knowledge_api.dart';
 import '../data/api/milestones_api.dart';
 import '../data/api/notes_api.dart';
 import '../data/api/projects_api.dart';
@@ -14,6 +15,7 @@ import '../data/api/settings_api.dart';
 import '../data/api/tasks_api.dart';
 import '../data/repositories/auth_repository.dart';
 import '../data/repositories/chat_repository.dart';
+import '../data/repositories/knowledge_repository.dart';
 import '../data/repositories/milestones_repository.dart';
 import '../data/repositories/notes_repository.dart';
 import '../data/repositories/projects_repository.dart';
@@ -83,6 +85,14 @@ final milestonesRepositoryProvider = Provider<MilestonesRepository>((ref) {
   return MilestonesRepository(ref.watch(milestonesApiProvider));
 });
 
+final knowledgeApiProvider = Provider<KnowledgeApi>((ref) {
+  return KnowledgeApi(ref.watch(dioProvider));
+});
+
+final knowledgeRepositoryProvider = Provider<KnowledgeRepository>((ref) {
+  return KnowledgeRepository(ref.watch(knowledgeApiProvider));
+});
+
 final briefingApiProvider = Provider<BriefingApi>((ref) {
   return BriefingApi(ref.watch(dioProvider));
 });