diff --git a/apps/api/src/knowledge/knowledge.controller.ts b/apps/api/src/knowledge/knowledge.controller.ts
index 27b1ad3..8819e23 100644
--- a/apps/api/src/knowledge/knowledge.controller.ts
+++ b/apps/api/src/knowledge/knowledge.controller.ts
@@ -30,8 +30,7 @@ import { KnowledgeCacheService } from "./services/cache.service";
 export class KnowledgeController {
   constructor(
     private readonly knowledgeService: KnowledgeService,
-    private readonly linkSync: LinkSyncService,
-    private readonly cache: KnowledgeCacheService
+    private readonly linkSync: LinkSyncService
   ) {}
 
   /**
diff --git a/apps/api/src/knowledge/services/cache.service.spec.ts b/apps/api/src/knowledge/services/cache.service.spec.ts
index 2784b3d..2e38820 100644
--- a/apps/api/src/knowledge/services/cache.service.spec.ts
+++ b/apps/api/src/knowledge/services/cache.service.spec.ts
@@ -1,3 +1,4 @@
+import { describe, it, expect, beforeEach, afterEach } from 'vitest';
 import { Test, TestingModule } from '@nestjs/testing';
 import { KnowledgeCacheService } from './cache.service';
 
diff --git a/apps/api/src/knowledge/services/cache.service.ts b/apps/api/src/knowledge/services/cache.service.ts
index ebe951a..1f7d7fa 100644
--- a/apps/api/src/knowledge/services/cache.service.ts
+++ b/apps/api/src/knowledge/services/cache.service.ts
@@ -37,7 +37,6 @@ export class KnowledgeCacheService implements OnModuleInit, OnModuleDestroy {
   private readonly ENTRY_PREFIX = 'knowledge:entry:';
   private readonly SEARCH_PREFIX = 'knowledge:search:';
   private readonly GRAPH_PREFIX = 'knowledge:graph:';
-  private readonly STATS_PREFIX = 'knowledge:stats:';
   
   // Default TTL from environment (default: 5 minutes)
   private readonly DEFAULT_TTL: number;
@@ -113,7 +112,7 @@ export class KnowledgeCacheService implements OnModuleInit, OnModuleDestroy {
   /**
    * Get entry from cache by workspace and slug
    */
-  async getEntry(workspaceId: string, slug: string): Promise<any | null> {
+  async getEntry<T = unknown>(workspaceId: string, slug: string): Promise<T | null> {
     if (!this.cacheEnabled) return null;
 
     try {
@@ -124,7 +123,7 @@ export class KnowledgeCacheService implements OnModuleInit, OnModuleDestroy {
         this.stats.hits++;
         this.updateHitRate();
         this.logger.debug(`Cache HIT: ${key}`);
-        return JSON.parse(cached);
+        return JSON.parse(cached) as T;
       }
       
       this.stats.misses++;
@@ -140,10 +139,10 @@ export class KnowledgeCacheService implements OnModuleInit, OnModuleDestroy {
   /**
    * Set entry in cache
    */
-  async setEntry(
+  async setEntry<T = unknown>(
     workspaceId: string,
     slug: string,
-    data: any,
+    data: T,
     options?: CacheOptions
   ): Promise<void> {
     if (!this.cacheEnabled) return;
@@ -182,11 +181,11 @@ export class KnowledgeCacheService implements OnModuleInit, OnModuleDestroy {
   /**
    * Get search results from cache
    */
-  async getSearch(
+  async getSearch<T = unknown>(
     workspaceId: string,
     query: string,
-    filters: Record<string, any>
-  ): Promise<any | null> {
+    filters: Record<string, unknown>
+  ): Promise<T | null> {
     if (!this.cacheEnabled) return null;
 
     try {
@@ -197,7 +196,7 @@ export class KnowledgeCacheService implements OnModuleInit, OnModuleDestroy {
         this.stats.hits++;
         this.updateHitRate();
         this.logger.debug(`Cache HIT: ${key}`);
-        return JSON.parse(cached);
+        return JSON.parse(cached) as T;
       }
       
       this.stats.misses++;
@@ -213,11 +212,11 @@ export class KnowledgeCacheService implements OnModuleInit, OnModuleDestroy {
   /**
    * Set search results in cache
    */
-  async setSearch(
+  async setSearch<T = unknown>(
     workspaceId: string,
     query: string,
-    filters: Record<string, any>,
-    data: any,
+    filters: Record<string, unknown>,
+    data: T,
     options?: CacheOptions
   ): Promise<void> {
     if (!this.cacheEnabled) return;
@@ -254,11 +253,11 @@ export class KnowledgeCacheService implements OnModuleInit, OnModuleDestroy {
   /**
    * Get graph query results from cache
    */
-  async getGraph(
+  async getGraph<T = unknown>(
     workspaceId: string,
     entryId: string,
     maxDepth: number
-  ): Promise<any | null> {
+  ): Promise<T | null> {
     if (!this.cacheEnabled) return null;
 
     try {
@@ -269,7 +268,7 @@ export class KnowledgeCacheService implements OnModuleInit, OnModuleDestroy {
         this.stats.hits++;
         this.updateHitRate();
         this.logger.debug(`Cache HIT: ${key}`);
-        return JSON.parse(cached);
+        return JSON.parse(cached) as T;
       }
       
       this.stats.misses++;
@@ -285,11 +284,11 @@ export class KnowledgeCacheService implements OnModuleInit, OnModuleDestroy {
   /**
    * Set graph query results in cache
    */
-  async setGraph(
+  async setGraph<T = unknown>(
     workspaceId: string,
     entryId: string,
     maxDepth: number,
-    data: any,
+    data: T,
     options?: CacheOptions
   ): Promise<void> {
     if (!this.cacheEnabled) return;
@@ -399,7 +398,7 @@ export class KnowledgeCacheService implements OnModuleInit, OnModuleDestroy {
   private getSearchKey(
     workspaceId: string,
     query: string,
-    filters: Record<string, any>
+    filters: Record<string, unknown>
   ): string {
     const filterHash = this.hashObject(filters);
     return `${this.SEARCH_PREFIX}${workspaceId}:${query}:${filterHash}`;
@@ -419,7 +418,7 @@ export class KnowledgeCacheService implements OnModuleInit, OnModuleDestroy {
   /**
    * Hash an object to create a consistent string representation
    */
-  private hashObject(obj: Record<string, any>): string {
+  private hashObject(obj: Record<string, unknown>): string {
     return JSON.stringify(obj, Object.keys(obj).sort());
   }