diff --git a/src/main/http/utility.ts b/src/main/http/utility.ts
index b3aa982f..e3839e71 100644
--- a/src/main/http/utility.ts
+++ b/src/main/http/utility.ts
@@ -111,6 +111,10 @@ export function registerUtilityRoutes(app: FastifyInstance): void {
           estimatedTokens,
         };
       } catch (error) {
+        // ENOENT is expected — file simply doesn't exist (e.g. stale or misdetected references)
+        if ((error as NodeJS.ErrnoException).code === 'ENOENT') {
+          return null;
+        }
         logger.error(
           `Error in POST /api/read-mentioned-file for ${request.body.absolutePath}:`,
           error
diff --git a/src/main/ipc/utility.ts b/src/main/ipc/utility.ts
index 2ff7642a..182beca9 100644
--- a/src/main/ipc/utility.ts
+++ b/src/main/ipc/utility.ts
@@ -256,6 +256,10 @@ async function handleReadMentionedFile(
       estimatedTokens,
     };
   } catch (error) {
+    // ENOENT is expected — file simply doesn't exist (e.g. stale or misdetected references)
+    if ((error as NodeJS.ErrnoException).code === 'ENOENT') {
+      return null;
+    }
     logger.error(`Error in read-mentioned-file for ${absolutePath}:`, error);
     return null;
   }
diff --git a/src/renderer/utils/groupTransformer.ts b/src/renderer/utils/groupTransformer.ts
index 6682fbca..0a975adf 100644
--- a/src/renderer/utils/groupTransformer.ts
+++ b/src/renderer/utils/groupTransformer.ts
@@ -13,7 +13,12 @@ import {
   isEnhancedSystemChunk,
   isEnhancedUserChunk,
 } from '@renderer/types/data';
-import { getFirstSegment, hasPathSeparator, isRelativePath } from '@renderer/utils/pathUtils';
+import {
+  getFirstSegment,
+  hasPathSeparator,
+  isRelativePath,
+  splitPathSegments,
+} from '@renderer/utils/pathUtils';
 import { isCommandContent, sanitizeDisplayContent } from '@shared/utils/contentSanitizer';
 import { createLogger } from '@shared/utils/logger';
 
@@ -369,8 +374,13 @@ function isValidFileRef(path: string): boolean {
     return true;
   }
   // Check if contains a path separator (indicates directory structure)
+  // Require either 3+ segments or a file extension to avoid matching
+  // npm scoped packages like @scope/name (extracted as "scope/name")
   if (hasPathSeparator(path) && path.length > 2) {
-    return true;
+    const segments = splitPathSegments(path);
+    if (segments.length > 2 || /\.[a-zA-Z0-9]+$/.test(path)) {
+      return true;
+    }
   }
   return false;
 }
diff --git a/test/renderer/utils/fileReferences.test.ts b/test/renderer/utils/fileReferences.test.ts
new file mode 100644
index 00000000..ee7e5c0c
--- /dev/null
+++ b/test/renderer/utils/fileReferences.test.ts
@@ -0,0 +1,158 @@
+import { describe, expect, it } from 'vitest';
+
+import { extractFileReferences } from '@renderer/utils/groupTransformer';
+
+describe('extractFileReferences', () => {
+  describe('accepts valid file references', () => {
+    it('accepts paths starting with known directories', () => {
+      const refs = extractFileReferences('Check @src/components/App.tsx');
+      expect(refs).toHaveLength(1);
+      expect(refs[0].path).toBe('src/components/App.tsx');
+    });
+
+    it('accepts utils/ paths (known dir)', () => {
+      const refs = extractFileReferences('See @utils/helpers');
+      expect(refs).toHaveLength(1);
+      expect(refs[0].path).toBe('utils/helpers');
+    });
+
+    it('accepts hooks/ paths (known dir)', () => {
+      const refs = extractFileReferences('Use @hooks/auth');
+      expect(refs).toHaveLength(1);
+      expect(refs[0].path).toBe('hooks/auth');
+    });
+
+    it('accepts lib/ paths (known dir)', () => {
+      const refs = extractFileReferences('In @lib/core');
+      expect(refs).toHaveLength(1);
+      expect(refs[0].path).toBe('lib/core');
+    });
+
+    it('accepts config/ paths (known dir)', () => {
+      const refs = extractFileReferences('Edit @config/database');
+      expect(refs).toHaveLength(1);
+      expect(refs[0].path).toBe('config/database');
+    });
+
+    it('accepts relative paths with ./', () => {
+      const refs = extractFileReferences('See @./src/file.ts');
+      expect(refs).toHaveLength(1);
+      expect(refs[0].path).toBe('./src/file.ts');
+    });
+
+    it('accepts relative paths with ../', () => {
+      const refs = extractFileReferences('See @../lib/utils.ts');
+      expect(refs).toHaveLength(1);
+      expect(refs[0].path).toBe('../lib/utils.ts');
+    });
+
+    it('accepts unknown-dir paths with 3+ segments', () => {
+      const refs = extractFileReferences('See @custom/deep/path.ts');
+      expect(refs).toHaveLength(1);
+      expect(refs[0].path).toBe('custom/deep/path.ts');
+    });
+
+    it('accepts unknown-dir paths with file extension', () => {
+      const refs = extractFileReferences('See @foo/bar.ts');
+      expect(refs).toHaveLength(1);
+      expect(refs[0].path).toBe('foo/bar.ts');
+    });
+
+    it('accepts node_modules paths (known dir)', () => {
+      const refs = extractFileReferences('Check @node_modules/lodash/index.js');
+      expect(refs).toHaveLength(1);
+      expect(refs[0].path).toBe('node_modules/lodash/index.js');
+    });
+
+    it('accepts types/ paths (known dir)', () => {
+      const refs = extractFileReferences('See @types/node');
+      expect(refs).toHaveLength(1);
+      expect(refs[0].path).toBe('types/node');
+    });
+
+    it('extracts multiple references from one string', () => {
+      const refs = extractFileReferences('Compare @src/a.ts and @lib/b.ts');
+      expect(refs).toHaveLength(2);
+      expect(refs[0].path).toBe('src/a.ts');
+      expect(refs[1].path).toBe('lib/b.ts');
+    });
+
+    it('accepts tilde paths', () => {
+      const refs = extractFileReferences('See @~/projects/foo');
+      expect(refs).toHaveLength(1);
+      expect(refs[0].path).toBe('~/projects/foo');
+    });
+  });
+
+  describe('rejects npm scoped packages', () => {
+    it('rejects @babel/core', () => {
+      const refs = extractFileReferences('Use @babel/core for transpilation');
+      expect(refs).toHaveLength(0);
+    });
+
+    it('rejects @xyflow/react', () => {
+      const refs = extractFileReferences('Install @xyflow/react');
+      expect(refs).toHaveLength(0);
+    });
+
+    it('rejects @dagrejs/dagre', () => {
+      const refs = extractFileReferences('Use @dagrejs/dagre for layout');
+      expect(refs).toHaveLength(0);
+    });
+
+    it('rejects @testing-library/react', () => {
+      const refs = extractFileReferences('Import from @testing-library/react');
+      expect(refs).toHaveLength(0);
+    });
+
+    it('rejects @vitest/ui', () => {
+      const refs = extractFileReferences('Run @vitest/ui');
+      expect(refs).toHaveLength(0);
+    });
+
+    it('rejects @radix-ui/react-dialog', () => {
+      const refs = extractFileReferences('Use @radix-ui/react-dialog');
+      expect(refs).toHaveLength(0);
+    });
+
+    it('rejects @codemirror/lang-javascript', () => {
+      const refs = extractFileReferences('Import @codemirror/lang-javascript');
+      expect(refs).toHaveLength(0);
+    });
+
+    it('rejects @emotion/react', () => {
+      const refs = extractFileReferences('Style with @emotion/react');
+      expect(refs).toHaveLength(0);
+    });
+  });
+
+  describe('edge cases', () => {
+    it('returns empty for text without @', () => {
+      const refs = extractFileReferences('No mentions here');
+      expect(refs).toHaveLength(0);
+    });
+
+    it('returns empty for empty string', () => {
+      const refs = extractFileReferences('');
+      expect(refs).toHaveLength(0);
+    });
+
+    it('rejects bare @ mentions without path separator', () => {
+      const refs = extractFileReferences('Hello @user');
+      expect(refs).toHaveLength(0);
+    });
+
+    it('handles mixed valid and invalid refs', () => {
+      const refs = extractFileReferences(
+        'Use @babel/core and check @src/components/App.tsx'
+      );
+      expect(refs).toHaveLength(1);
+      expect(refs[0].path).toBe('src/components/App.tsx');
+    });
+
+    it('rejects single-segment bare names', () => {
+      const refs = extractFileReferences('@react is a library');
+      expect(refs).toHaveLength(0);
+    });
+  });
+});