diff --git a/src/utils/websearch/hook-utils.ts b/src/utils/websearch/hook-utils.ts
index 7a551380..65607b34 100644
--- a/src/utils/websearch/hook-utils.ts
+++ b/src/utils/websearch/hook-utils.ts
@@ -48,5 +48,11 @@ export function deduplicateCcsHooks(settings: Record<string, unknown>): boolean
     return false; // Remove subsequent duplicates
   });
 
-  return hooks.PreToolUse.length < originalLength;
+  const newLength = hooks.PreToolUse.length;
+  if (process.env.CCS_DEBUG && newLength < originalLength) {
+    const removedCount = originalLength - newLength;
+    console.error(`Removed ${removedCount} duplicate CCS WebSearch hook(s)`);
+  }
+
+  return newLength < originalLength;
 }
diff --git a/src/web-server/routes/settings-routes.ts b/src/web-server/routes/settings-routes.ts
index baaa73a9..dc4c5063 100644
--- a/src/web-server/routes/settings-routes.ts
+++ b/src/web-server/routes/settings-routes.ts
@@ -18,6 +18,7 @@ import {
   resetAuthToDefaults,
 } from '../../cliproxy';
 import { regenerateConfig } from '../../cliproxy/config-generator';
+import { deduplicateCcsHooks } from '../../utils/websearch/hook-utils';
 import type { Settings } from '../../types/config';
 
 const router = Router();
@@ -136,6 +137,10 @@ router.put('/:profile', (req: Request, res: Response): void => {
       return;
     }
 
+    // Deduplicate CCS hooks to prevent accumulation (fixes #450)
+    // This handles cases where duplicate hooks were added by previous versions
+    deduplicateCcsHooks(settings as Record<string, unknown>);
+
     const ccsDir = getCcsDir();
 
     // Check for missing required fields (warning, not blocking - runtime fills defaults)
diff --git a/tests/unit/glmt/retry-logic.test.ts b/tests/unit/glmt/retry-logic.test.ts
index ab289fd1..6523cbfa 100644
--- a/tests/unit/glmt/retry-logic.test.ts
+++ b/tests/unit/glmt/retry-logic.test.ts
@@ -4,7 +4,10 @@
  * Tests for exponential backoff retry behavior on 429 rate limit errors
  */
 
-import { describe, it, expect, beforeEach, afterEach } from 'bun:test';
+import { describe, it, expect, beforeEach, afterEach, setDefaultTimeout } from 'bun:test';
+
+// Increase timeout for CI - dynamic imports and proxy creation are slow on CI runners
+setDefaultTimeout(30000);
 
 // Store original env vars
 const originalEnv = { ...process.env };
diff --git a/tests/unit/utils/websearch/hook-utils.test.ts b/tests/unit/utils/websearch/hook-utils.test.ts
index a3f7bd3e..64373365 100644
--- a/tests/unit/utils/websearch/hook-utils.test.ts
+++ b/tests/unit/utils/websearch/hook-utils.test.ts
@@ -289,4 +289,83 @@ describe('deduplicateCcsHooks', () => {
     expect(result).toBe(false);
     expect(settings.hooks.PreToolUse).toHaveLength(0);
   });
+
+  test('Stress test: 15 duplicate CCS WebSearch hooks', () => {
+    const ccsHook = {
+      matcher: 'WebSearch',
+      hooks: [
+        {
+          command: 'node /home/user/.ccs/hooks/websearch-transformer/index.js',
+        },
+      ],
+    };
+    const settings = {
+      hooks: {
+        PreToolUse: Array(15).fill(ccsHook),
+      },
+    };
+    const result = deduplicateCcsHooks(settings);
+    expect(result).toBe(true);
+    expect(settings.hooks.PreToolUse).toHaveLength(1);
+    expect(settings.hooks.PreToolUse[0]).toEqual(ccsHook);
+  });
+
+  test('Leaves PostToolUse and PreToolCall untouched', () => {
+    const postToolUseHook1 = {
+      matcher: 'CustomMatcher1',
+      hooks: [{ command: 'custom-command-1' }],
+    };
+    const postToolUseHook2 = {
+      matcher: 'CustomMatcher2',
+      hooks: [{ command: 'custom-command-2' }],
+    };
+    const preToolCallHook = {
+      matcher: 'CustomMatcher3',
+      hooks: [{ command: 'custom-command-3' }],
+    };
+    const settings = {
+      hooks: {
+        PreToolUse: [
+          {
+            matcher: 'WebSearch',
+            hooks: [
+              {
+                command: 'node /path1/.ccs/hooks/websearch-transformer/index.js',
+              },
+            ],
+          },
+          {
+            matcher: 'WebSearch',
+            hooks: [
+              {
+                command: 'node /path2/.ccs/hooks/websearch-transformer/index.js',
+              },
+            ],
+          },
+          {
+            matcher: 'WebSearch',
+            hooks: [
+              {
+                command: 'node /path3/.ccs/hooks/websearch-transformer/index.js',
+              },
+            ],
+          },
+        ],
+        PostToolUse: [postToolUseHook1, postToolUseHook2],
+        PreToolCall: [preToolCallHook],
+      },
+    };
+    const result = deduplicateCcsHooks(settings);
+    expect(result).toBe(true);
+    // PreToolUse should be deduplicated to 1 hook
+    expect(settings.hooks.PreToolUse).toHaveLength(1);
+    expect(settings.hooks.PreToolUse[0].matcher).toBe('WebSearch');
+    // PostToolUse should remain unchanged with 2 hooks
+    expect(settings.hooks.PostToolUse).toHaveLength(2);
+    expect(settings.hooks.PostToolUse[0]).toEqual(postToolUseHook1);
+    expect(settings.hooks.PostToolUse[1]).toEqual(postToolUseHook2);
+    // PreToolCall should remain unchanged with 1 hook
+    expect(settings.hooks.PreToolCall).toHaveLength(1);
+    expect(settings.hooks.PreToolCall[0]).toEqual(preToolCallHook);
+  });
 });