diff --git a/docs/cli/plan-mode.md b/docs/cli/plan-mode.md
index 51f0078206..dce7e2886e 100644
--- a/docs/cli/plan-mode.md
+++ b/docs/cli/plan-mode.md
@@ -28,6 +28,7 @@ implementation. It allows you to:
     - [Example: Enable research subagents in Plan Mode](#example-enable-research-subagents-in-plan-mode)
   - [Custom Plan Directory and Policies](#custom-plan-directory-and-policies)
 - [Automatic Model Routing](#automatic-model-routing)
+- [Cleanup](#cleanup)
 
 ## Enabling Plan Mode
 
@@ -290,6 +291,24 @@ performance. You can disable this automatic switching in your settings:
 }
 ```
 
+## Cleanup
+
+By default, Gemini CLI automatically cleans up old session data, including all
+associated plan files and task trackers.
+
+- **Default behavior:** Sessions (and their plans) are retained for **30 days**.
+- **Configuration:** You can customize this behavior via the `/settings` command
+  (search for **Session Retention**) or in your `settings.json` file. See
+  [session retention] for more details.
+
+Manual deletion also removes all associated artifacts:
+
+- **Command Line:** Use `gemini --delete-session <index|id>`.
+- **Session Browser:** Press `/resume`, navigate to a session, and press `x`.
+
+If you use a [custom plans directory](#custom-plan-directory-and-policies),
+those files are not automatically deleted and must be managed manually.
+
 [`list_directory`]: /docs/tools/file-system.md#1-list_directory-readfolder
 [`read_file`]: /docs/tools/file-system.md#2-read_file-readfile
 [`grep_search`]: /docs/tools/file-system.md#5-grep_search-searchtext
@@ -311,3 +330,4 @@ performance. You can disable this automatic switching in your settings:
 [auto model]: /docs/reference/configuration.md#model-settings
 [model routing]: /docs/cli/telemetry.md#model-routing
 [preferred external editor]: /docs/reference/configuration.md#general
+[session retention]: /docs/cli/session-management.md#session-retention
diff --git a/docs/cli/session-management.md b/docs/cli/session-management.md
index a1453148ae..442069bdac 100644
--- a/docs/cli/session-management.md
+++ b/docs/cli/session-management.md
@@ -121,27 +121,36 @@ session lengths.
 
 ### Session retention
 
-To prevent your history from growing indefinitely, enable automatic cleanup
-policies in your settings.
+By default, Gemini CLI automatically cleans up old session data to prevent your
+history from growing indefinitely. When a session is deleted, Gemini CLI also
+removes all associated data, including implementation plans, task trackers, tool
+outputs, and activity logs.
+
+The default policy is to **retain sessions for 30 days**.
+
+#### Configuration
+
+You can customize these policies using the `/settings` command or by manually
+editing your `settings.json` file:
 
 ```json
 {
   "general": {
     "sessionRetention": {
       "enabled": true,
-      "maxAge": "30d", // Keep sessions for 30 days
-      "maxCount": 50 // Keep the 50 most recent sessions
+      "maxAge": "30d",
+      "maxCount": 50
     }
   }
 }
 ```
 
 - **`enabled`**: (boolean) Master switch for session cleanup. Defaults to
-  `false`.
+  `true`.
 - **`maxAge`**: (string) Duration to keep sessions (for example, "24h", "7d",
-  "4w"). Sessions older than this are deleted.
+  "4w"). Sessions older than this are deleted. Defaults to `"30d"`.
 - **`maxCount`**: (number) Maximum number of sessions to retain. The oldest
-  sessions exceeding this count are deleted.
+  sessions exceeding this count are deleted. Defaults to undefined (unlimited).
 - **`minRetention`**: (string) Minimum retention period (safety limit). Defaults
   to `"1d"`. Sessions newer than this period are never deleted by automatic
   cleanup.
diff --git a/packages/cli/src/utils/sessionCleanup.test.ts b/packages/cli/src/utils/sessionCleanup.test.ts
index cc775d01c9..bcd55953e8 100644
--- a/packages/cli/src/utils/sessionCleanup.test.ts
+++ b/packages/cli/src/utils/sessionCleanup.test.ts
@@ -919,6 +919,32 @@ describe('Session Cleanup', () => {
         ),
       );
     });
+
+    it('should delete the session-specific directory', async () => {
+      const config = createMockConfig();
+      const settings: Settings = {
+        general: {
+          sessionRetention: {
+            enabled: true,
+            maxAge: '1d', // Very short retention to trigger deletion of all but current
+          },
+        },
+      };
+
+      // Mock successful file operations
+      mockFs.access.mockResolvedValue(undefined);
+      mockFs.unlink.mockResolvedValue(undefined);
+      mockFs.rm.mockResolvedValue(undefined);
+
+      await cleanupExpiredSessions(config, settings);
+
+      // Verify that fs.rm was called with the session directory for the deleted session that has sessionInfo
+      // recent456 should be deleted and its directory removed
+      expect(mockFs.rm).toHaveBeenCalledWith(
+        path.join('/tmp/test-project', 'recent456'),
+        expect.objectContaining({ recursive: true, force: true }),
+      );
+    });
   });
 
   describe('parseRetentionPeriod format validation', () => {
diff --git a/packages/cli/src/utils/sessionCleanup.ts b/packages/cli/src/utils/sessionCleanup.ts
index 64e3b4c565..57f2fdd189 100644
--- a/packages/cli/src/utils/sessionCleanup.ts
+++ b/packages/cli/src/utils/sessionCleanup.ts
@@ -115,6 +115,17 @@ export async function cleanupExpiredSessions(
           } catch {
             /* ignore if doesn't exist */
           }
+
+          // ALSO cleanup the session-specific directory (contains plans, tasks, etc.)
+          const sessionDir = path.join(
+            config.storage.getProjectTempDir(),
+            sessionId,
+          );
+          try {
+            await fs.rm(sessionDir, { recursive: true, force: true });
+          } catch {
+            /* ignore if doesn't exist */
+          }
         }
 
         if (config.getDebugMode()) {
diff --git a/packages/core/src/services/chatRecordingService.test.ts b/packages/core/src/services/chatRecordingService.test.ts
index 086a7b6ff5..50a363a1db 100644
--- a/packages/core/src/services/chatRecordingService.test.ts
+++ b/packages/core/src/services/chatRecordingService.test.ts
@@ -309,23 +309,33 @@ describe('ChatRecordingService', () => {
   });
 
   describe('deleteSession', () => {
-    it('should delete the session file and tool outputs if they exist', () => {
+    it('should delete the session file, tool outputs, session directory, and logs if they exist', () => {
+      const sessionId = 'test-session-id';
       const chatsDir = path.join(testTempDir, 'chats');
+      const logsDir = path.join(testTempDir, 'logs');
+      const toolOutputsDir = path.join(testTempDir, 'tool-outputs');
+      const sessionDir = path.join(testTempDir, sessionId);
+
       fs.mkdirSync(chatsDir, { recursive: true });
-      const sessionFile = path.join(chatsDir, 'test-session-id.json');
+      fs.mkdirSync(logsDir, { recursive: true });
+      fs.mkdirSync(toolOutputsDir, { recursive: true });
+      fs.mkdirSync(sessionDir, { recursive: true });
+
+      const sessionFile = path.join(chatsDir, `${sessionId}.json`);
       fs.writeFileSync(sessionFile, '{}');
 
-      const toolOutputDir = path.join(
-        testTempDir,
-        'tool-outputs',
-        'session-test-session-id',
-      );
+      const logFile = path.join(logsDir, `session-${sessionId}.jsonl`);
+      fs.writeFileSync(logFile, '{}');
+
+      const toolOutputDir = path.join(toolOutputsDir, `session-${sessionId}`);
       fs.mkdirSync(toolOutputDir, { recursive: true });
 
-      chatRecordingService.deleteSession('test-session-id');
+      chatRecordingService.deleteSession(sessionId);
 
       expect(fs.existsSync(sessionFile)).toBe(false);
+      expect(fs.existsSync(logFile)).toBe(false);
       expect(fs.existsSync(toolOutputDir)).toBe(false);
+      expect(fs.existsSync(sessionDir)).toBe(false);
     });
 
     it('should not throw if session file does not exist', () => {
diff --git a/packages/core/src/services/chatRecordingService.ts b/packages/core/src/services/chatRecordingService.ts
index 2afbd16657..1748ccbe20 100644
--- a/packages/core/src/services/chatRecordingService.ts
+++ b/packages/core/src/services/chatRecordingService.ts
@@ -569,6 +569,13 @@ export class ChatRecordingService {
         fs.unlinkSync(sessionPath);
       }
 
+      // Cleanup Activity logs in the project logs directory
+      const logsDir = path.join(tempDir, 'logs');
+      const logPath = path.join(logsDir, `session-${sessionId}.jsonl`);
+      if (fs.existsSync(logPath)) {
+        fs.unlinkSync(logPath);
+      }
+
       // Cleanup tool outputs for this session
       const safeSessionId = sanitizeFilenamePart(sessionId);
       const toolOutputDir = path.join(
@@ -585,6 +592,13 @@ export class ChatRecordingService {
       ) {
         fs.rmSync(toolOutputDir, { recursive: true, force: true });
       }
+
+      // ALSO cleanup the session-specific directory (contains plans, tasks, etc.)
+      const sessionDir = path.join(tempDir, safeSessionId);
+      // Robustness: Ensure the path is strictly within the temp root
+      if (fs.existsSync(sessionDir) && sessionDir.startsWith(tempDir)) {
+        fs.rmSync(sessionDir, { recursive: true, force: true });
+      }
     } catch (error) {
       debugLogger.error('Error deleting session file.', error);
       throw error;