diff --git a/packages/core/src/tools/edit.test.ts b/packages/core/src/tools/edit.test.ts
index 50f68e2a..9143f3bd 100644
--- a/packages/core/src/tools/edit.test.ts
+++ b/packages/core/src/tools/edit.test.ts
@@ -549,6 +549,65 @@ describe('EditTool', () => {
         /Attempted to create a file that already exists/,
       );
     });
+
+    it('should include modification message when proposed content is modified', async () => {
+      const initialContent = 'This is some old text.';
+      fs.writeFileSync(filePath, initialContent, 'utf8');
+      const params: EditToolParams = {
+        file_path: filePath,
+        old_string: 'old',
+        new_string: 'new',
+        modified_by_user: true,
+      };
+
+      (mockConfig.getApprovalMode as Mock).mockReturnValueOnce(
+        ApprovalMode.AUTO_EDIT,
+      );
+      const result = await tool.execute(params, new AbortController().signal);
+
+      expect(result.llmContent).toMatch(
+        /User modified the `new_string` content/,
+      );
+    });
+
+    it('should not include modification message when proposed content is not modified', async () => {
+      const initialContent = 'This is some old text.';
+      fs.writeFileSync(filePath, initialContent, 'utf8');
+      const params: EditToolParams = {
+        file_path: filePath,
+        old_string: 'old',
+        new_string: 'new',
+        modified_by_user: false,
+      };
+
+      (mockConfig.getApprovalMode as Mock).mockReturnValueOnce(
+        ApprovalMode.AUTO_EDIT,
+      );
+      const result = await tool.execute(params, new AbortController().signal);
+
+      expect(result.llmContent).not.toMatch(
+        /User modified the `new_string` content/,
+      );
+    });
+
+    it('should not include modification message when modified_by_user is not provided', async () => {
+      const initialContent = 'This is some old text.';
+      fs.writeFileSync(filePath, initialContent, 'utf8');
+      const params: EditToolParams = {
+        file_path: filePath,
+        old_string: 'old',
+        new_string: 'new',
+      };
+
+      (mockConfig.getApprovalMode as Mock).mockReturnValueOnce(
+        ApprovalMode.AUTO_EDIT,
+      );
+      const result = await tool.execute(params, new AbortController().signal);
+
+      expect(result.llmContent).not.toMatch(
+        /User modified the `new_string` content/,
+      );
+    });
   });
 
   describe('getDescription', () => {
diff --git a/packages/core/src/tools/edit.ts b/packages/core/src/tools/edit.ts
index ddb521be..2515261d 100644
--- a/packages/core/src/tools/edit.ts
+++ b/packages/core/src/tools/edit.ts
@@ -49,6 +49,11 @@ export interface EditToolParams {
    * Use when you want to replace multiple occurrences.
    */
   expected_replacements?: number;
+
+  /**
+   * Whether the edit was modified manually by the user.
+   */
+  modified_by_user?: boolean;
 }
 
 interface CalculatedEdit {
@@ -81,6 +86,8 @@ export class EditTool
       'Edit',
       `Replaces text within a file. By default, replaces a single occurrence, but can replace multiple occurrences when \`expected_replacements\` is specified. This tool requires providing significant context around the change to ensure precise targeting. Always use the ${ReadFileTool.Name} tool to examine the file's current content before attempting a text replacement.
 
+      The user has the ability to modify the \`new_string\` content. If modified, this will be stated in the response.
+
 Expectation for required parameters:
 1. \`file_path\` MUST be an absolute path; otherwise an error will be thrown.
 2. \`old_string\` MUST be the exact literal text to replace (including all whitespace, indentation, newlines, and surrounding code etc.).
@@ -414,12 +421,19 @@ Expectation for required parameters:
         displayResult = { fileDiff, fileName };
       }
 
-      const llmSuccessMessage = editData.isNewFile
-        ? `Created new file: ${params.file_path} with provided content.`
-        : `Successfully modified file: ${params.file_path} (${editData.occurrences} replacements).`;
+      const llmSuccessMessageParts = [
+        editData.isNewFile
+          ? `Created new file: ${params.file_path} with provided content.`
+          : `Successfully modified file: ${params.file_path} (${editData.occurrences} replacements).`,
+      ];
+      if (params.modified_by_user) {
+        llmSuccessMessageParts.push(
+          `User modified the \`new_string\` content to be: ${params.new_string}.`,
+        );
+      }
 
       return {
-        llmContent: llmSuccessMessage,
+        llmContent: llmSuccessMessageParts.join(' '),
         returnDisplay: displayResult,
       };
     } catch (error) {
@@ -474,6 +488,7 @@ Expectation for required parameters:
         ...originalParams,
         old_string: oldContent,
         new_string: modifiedProposedContent,
+        modified_by_user: true,
       }),
     };
   }
diff --git a/packages/core/src/tools/write-file.test.ts b/packages/core/src/tools/write-file.test.ts
index 4646f30a..3f9825c6 100644
--- a/packages/core/src/tools/write-file.test.ts
+++ b/packages/core/src/tools/write-file.test.ts
@@ -567,5 +567,49 @@ describe('WriteFileTool', () => {
       expect(fs.existsSync(filePath)).toBe(true);
       expect(fs.readFileSync(filePath, 'utf8')).toBe(content);
     });
+
+    it('should include modification message when proposed content is modified', async () => {
+      const filePath = path.join(rootDir, 'new_file_modified.txt');
+      const content = 'New file content modified by user';
+      mockEnsureCorrectFileContent.mockResolvedValue(content);
+
+      const params = {
+        file_path: filePath,
+        content,
+        modified_by_user: true,
+      };
+      const result = await tool.execute(params, abortSignal);
+
+      expect(result.llmContent).toMatch(/User modified the `content`/);
+    });
+
+    it('should not include modification message when proposed content is not modified', async () => {
+      const filePath = path.join(rootDir, 'new_file_unmodified.txt');
+      const content = 'New file content not modified';
+      mockEnsureCorrectFileContent.mockResolvedValue(content);
+
+      const params = {
+        file_path: filePath,
+        content,
+        modified_by_user: false,
+      };
+      const result = await tool.execute(params, abortSignal);
+
+      expect(result.llmContent).not.toMatch(/User modified the `content`/);
+    });
+
+    it('should not include modification message when modified_by_user is not provided', async () => {
+      const filePath = path.join(rootDir, 'new_file_unmodified.txt');
+      const content = 'New file content not modified';
+      mockEnsureCorrectFileContent.mockResolvedValue(content);
+
+      const params = {
+        file_path: filePath,
+        content,
+      };
+      const result = await tool.execute(params, abortSignal);
+
+      expect(result.llmContent).not.toMatch(/User modified the `content`/);
+    });
   });
 });
diff --git a/packages/core/src/tools/write-file.ts b/packages/core/src/tools/write-file.ts
index 87f6e21e..2d5e85be 100644
--- a/packages/core/src/tools/write-file.ts
+++ b/packages/core/src/tools/write-file.ts
@@ -45,6 +45,11 @@ export interface WriteFileToolParams {
    * The content to write to the file
    */
   content: string;
+
+  /**
+   * Whether the proposed content was modified by the user.
+   */
+  modified_by_user?: boolean;
 }
 
 interface GetCorrectedFileContentResult {
@@ -68,7 +73,9 @@ export class WriteFileTool
     super(
       WriteFileTool.Name,
       'WriteFile',
-      'Writes content to a specified file in the local filesystem.',
+      `Writes content to a specified file in the local filesystem. 
+      
+      The user has the ability to modify \`content\`. If modified, this will be stated in the response.`,
       {
         properties: {
           file_path: {
@@ -270,9 +277,16 @@ export class WriteFileTool
         DEFAULT_DIFF_OPTIONS,
       );
 
-      const llmSuccessMessage = isNewFile
-        ? `Successfully created and wrote to new file: ${params.file_path}`
-        : `Successfully overwrote file: ${params.file_path}`;
+      const llmSuccessMessageParts = [
+        isNewFile
+          ? `Successfully created and wrote to new file: ${params.file_path}.`
+          : `Successfully overwrote file: ${params.file_path}.`,
+      ];
+      if (params.modified_by_user) {
+        llmSuccessMessageParts.push(
+          `User modified the \`content\` to be: ${params.content}`,
+        );
+      }
 
       const displayResult: FileDiff = { fileDiff, fileName };
 
@@ -298,7 +312,7 @@ export class WriteFileTool
       }
 
       return {
-        llmContent: llmSuccessMessage,
+        llmContent: llmSuccessMessageParts.join(' '),
         returnDisplay: displayResult,
       };
     } catch (error) {
@@ -395,6 +409,7 @@ export class WriteFileTool
       ) => ({
         ...originalParams,
         content: modifiedProposedContent,
+        modified_by_user: true,
       }),
     };
   }