diff --git a/packages/core/src/tools/read-file.test.ts b/packages/core/src/tools/read-file.test.ts
index b3c80214499..e0003f82086 100644
--- a/packages/core/src/tools/read-file.test.ts
+++ b/packages/core/src/tools/read-file.test.ts
@@ -480,6 +480,14 @@ describe('ReadFileTool', () => {
       expect(() => tool.build(params)).not.toThrow();
     });
 
+    it('should treat empty pages parameter as unset', () => {
+      const params: ReadFileToolParams = {
+        file_path: path.join(tempRootDir, 'test.txt'),
+        pages: '',
+      };
+      expect(() => tool.build(params)).not.toThrow();
+    });
+
     it('should support offset and limit for text files', async () => {
       const filePath = path.join(tempRootDir, 'paginated.txt');
       const lines = Array.from({ length: 20 }, (_, i) => `Line ${i + 1}`);
diff --git a/packages/core/src/tools/read-file.ts b/packages/core/src/tools/read-file.ts
index 315ddd6b170..c05740b524c 100644
--- a/packages/core/src/tools/read-file.ts
+++ b/packages/core/src/tools/read-file.ts
@@ -264,7 +264,7 @@ export class ReadFileTool extends BaseDeclarativeTool<
       return 'Limit must be a positive number';
     }
 
-    if (params.pages !== undefined) {
+    if (params.pages) {
       const parsed = parsePDFPageRange(params.pages);
       if (!parsed) {
         return `Invalid pages parameter: '${params.pages}'. Use formats like '5' or '1-10'.`;