feat(core): overhaul system prompt for rigor, integrity, and intent alignment (#17263)

packages/core/src/utils/environmentContext.test.ts

@@ -49,11 +49,10 @@ describe('getDirectoryContextString', () => {
 
   it('should return context string for a single directory', async () => {
     const contextString = await getDirectoryContextString(mockConfig as Config);
+    expect(contextString).toContain('- **Workspace Directories:**');
+    expect(contextString).toContain('  - /test/dir');
     expect(contextString).toContain(
-      "I'm currently working in the directory: /test/dir",
-    );
-    expect(contextString).toContain(
-      'Here is the folder structure of the current working directories:\n\nMock Folder Structure',
+      '- **Directory Structure:**\n\nMock Folder Structure',
     );
   });
 
@@ -66,11 +65,11 @@ describe('getDirectoryContextString', () => {
       .mockResolvedValueOnce('Structure 2');
 
     const contextString = await getDirectoryContextString(mockConfig as Config);
+    expect(contextString).toContain('- **Workspace Directories:**');
+    expect(contextString).toContain('  - /test/dir1');
+    expect(contextString).toContain('  - /test/dir2');
     expect(contextString).toContain(
-      "I'm currently working in the following directories:\n  - /test/dir1\n  - /test/dir2",
-    );
-    expect(contextString).toContain(
-      'Here is the folder structure of the current working directories:\n\nStructure 1\nStructure 2',
+      '- **Directory Structure:**\n\nStructure 1\nStructure 2',
     );
   });
 });
@@ -80,9 +79,6 @@ describe('getEnvironmentContext', () => {
   let mockToolRegistry: { getTool: Mock };
 
   beforeEach(() => {
-    vi.useFakeTimers();
-    vi.setSystemTime(new Date('2025-08-05T12:00:00Z'));
-
     mockToolRegistry = {
       getTool: vi.fn(),
     };
@@ -104,7 +100,6 @@ describe('getEnvironmentContext', () => {
   });
 
   afterEach(() => {
-    vi.useRealTimers();
     vi.resetAllMocks();
   });
 
@@ -114,16 +109,14 @@ describe('getEnvironmentContext', () => {
     expect(parts.length).toBe(1);
     const context = parts[0].text;
 
-    expect(context).toContain("Today's date is");
-    expect(context).toContain("(formatted according to the user's locale)");
-    expect(context).toContain(`My operating system is: ${process.platform}`);
+    expect(context).toContain('<session_context>');
+    expect(context).toContain('- **Workspace Directories:**');
+    expect(context).toContain('  - /test/dir');
     expect(context).toContain(
-      "I'm currently working in the directory: /test/dir",
-    );
-    expect(context).toContain(
-      'Here is the folder structure of the current working directories:\n\nMock Folder Structure',
+      '- **Directory Structure:**\n\nMock Folder Structure',
     );
     expect(context).toContain('Mock Environment Memory');
+    expect(context).toContain('</session_context>');
     expect(getFolderStructure).toHaveBeenCalledWith('/test/dir', {
       fileService: undefined,
     });
@@ -142,12 +135,14 @@ describe('getEnvironmentContext', () => {
     expect(parts.length).toBe(1);
     const context = parts[0].text;
 
+    expect(context).toContain('<session_context>');
+    expect(context).toContain('- **Workspace Directories:**');
+    expect(context).toContain('  - /test/dir1');
+    expect(context).toContain('  - /test/dir2');
     expect(context).toContain(
-      "I'm currently working in the following directories:\n  - /test/dir1\n  - /test/dir2",
-    );
-    expect(context).toContain(
-      'Here is the folder structure of the current working directories:\n\nStructure 1\nStructure 2',
+      '- **Directory Structure:**\n\nStructure 1\nStructure 2',
     );
+    expect(context).toContain('</session_context>');
     expect(getFolderStructure).toHaveBeenCalledTimes(2);
   });
 

packages/core/src/utils/environmentContext.ts

@@ -30,17 +30,10 @@ export async function getDirectoryContextString(
   );
 
   const folderStructure = folderStructures.join('\n');
+  const dirList = workspaceDirectories.map((dir) => `  - ${dir}`).join('\n');
 
-  let workingDirPreamble: string;
-  if (workspaceDirectories.length === 1) {
-    workingDirPreamble = `I'm currently working in the directory: ${workspaceDirectories[0]}`;
-  } else {
-    const dirList = workspaceDirectories.map((dir) => `  - ${dir}`).join('\n');
-    workingDirPreamble = `I'm currently working in the following directories:\n${dirList}`;
-  }
-
-  return `${workingDirPreamble}
-Here is the folder structure of the current working directories:
+  return `- **Workspace Directories:**\n${dirList}
+- **Directory Structure:**
 
 ${folderStructure}`;
 }
@@ -65,6 +58,7 @@ export async function getEnvironmentContext(config: Config): Promise<Part[]> {
   const environmentMemory = config.getEnvironmentMemory();
 
   const context = `
+<session_context>
 This is the Gemini CLI. We are setting up the context for our chat.
 Today's date is ${today} (formatted according to the user's locale).
 My operating system is: ${platform}
@@ -72,7 +66,7 @@ The project's temporary directory is: ${tempDir}
 ${directoryContext}
 
 ${environmentMemory}
-        `.trim();
+</session_context>`.trim();
 
   const initialParts: Part[] = [{ text: context }];
 
@@ -86,18 +80,10 @@ export async function getInitialChatHistory(
   const envParts = await getEnvironmentContext(config);
   const envContextString = envParts.map((part) => part.text || '').join('\n\n');
 
-  const allSetupText = `
-${envContextString}
-
-Reminder: Do not return an empty response when a tool call is required.
-
-My setup is complete. I will provide my first command in the next turn.
-    `.trim();
-
   return [
     {
       role: 'user',
-      parts: [{ text: allSetupText }],
+      parts: [{ text: envContextString }],
     },
     ...(extraHistory ?? []),
   ];