fix(cli): preserve legacy auto memory behavior

packages/cli/src/config/settings.test.ts

@@ -339,6 +339,69 @@ describe('Settings Loading and Merging', () => {
       });
     });
 
+    it('should preserve legacy auto memory behavior when only memoryManager is explicitly enabled', () => {
+      (mockFsExistsSync as Mock).mockImplementation((p: fs.PathLike) => {
+        const normP = path.normalize(p.toString());
+        return (
+          normP === path.normalize(USER_SETTINGS_PATH) ||
+          normP === path.normalize(MOCK_WORKSPACE_SETTINGS_PATH)
+        );
+      });
+
+      const userSettingsContent = {
+        experimental: {
+          memoryManager: true,
+        },
+      };
+
+      (fs.readFileSync as Mock).mockImplementation(
+        (p: fs.PathOrFileDescriptor) => {
+          const normP = path.normalize(p.toString());
+          if (normP === path.normalize(USER_SETTINGS_PATH)) {
+            return JSON.stringify(userSettingsContent);
+          }
+          return '{}';
+        },
+      );
+
+      const settings = loadSettings(MOCK_WORKSPACE_DIR);
+
+      expect(settings.merged.experimental?.memoryManager).toBe(true);
+      expect(settings.merged.experimental?.autoMemory).toBe(true);
+    });
+
+    it('should let explicit autoMemory false override legacy memoryManager compatibility', () => {
+      (mockFsExistsSync as Mock).mockImplementation((p: fs.PathLike) => {
+        const normP = path.normalize(p.toString());
+        return (
+          normP === path.normalize(USER_SETTINGS_PATH) ||
+          normP === path.normalize(MOCK_WORKSPACE_SETTINGS_PATH)
+        );
+      });
+
+      const userSettingsContent = {
+        experimental: {
+          memoryManager: true,
+          autoMemory: false,
+        },
+      };
+
+      (fs.readFileSync as Mock).mockImplementation(
+        (p: fs.PathOrFileDescriptor) => {
+          const normP = path.normalize(p.toString());
+          if (normP === path.normalize(USER_SETTINGS_PATH)) {
+            return JSON.stringify(userSettingsContent);
+          }
+          return '{}';
+        },
+      );
+
+      const settings = loadSettings(MOCK_WORKSPACE_DIR);
+
+      expect(settings.merged.experimental?.memoryManager).toBe(true);
+      expect(settings.merged.experimental?.autoMemory).toBe(false);
+    });
+
     it('should merge all settings files with the correct precedence', () => {
       // Mock schema to test defaults application
       const mockSchema = {

packages/cli/src/config/settings.ts

@@ -244,6 +244,28 @@ export function getDefaultsFromSchema(
   return defaults as Settings;
 }
 
+function hasOwnNestedProperty(
+  obj: Settings | undefined,
+  path: string[],
+): boolean {
+  let current: unknown = obj;
+
+  for (const key of path) {
+    if (typeof current !== 'object' || current === null) {
+      return false;
+    }
+
+    const record = current as Record<string, unknown>;
+    if (!Object.hasOwn(record, key)) {
+      return false;
+    }
+
+    current = record[key];
+  }
+
+  return true;
+}
+
 export function mergeSettings(
   system: Settings,
   systemDefaults: Settings,
@@ -262,14 +284,30 @@ export function mergeSettings(
   // 4. Workspace Settings
   // 5. System Settings (as overrides)
   // eslint-disable-next-line @typescript-eslint/no-unsafe-type-assertion
-  return customDeepMerge(
+  const merged = customDeepMerge(
     getMergeStrategyForPath,
     schemaDefaults,
     systemDefaults,
     user,
     safeWorkspace,
     system,
   ) as MergedSettings;
+
+  const hasExplicitAutoMemory =
+    hasOwnNestedProperty(system, ['experimental', 'autoMemory']) ||
+    hasOwnNestedProperty(systemDefaults, ['experimental', 'autoMemory']) ||
+    hasOwnNestedProperty(user, ['experimental', 'autoMemory']) ||
+    hasOwnNestedProperty(safeWorkspace, ['experimental', 'autoMemory']);
+
+  if (
+    !hasExplicitAutoMemory &&
+    merged.experimental?.memoryManager &&
+    merged.experimental
+  ) {
+    merged.experimental.autoMemory = true;
+  }
+
+  return merged;
 }
 
 /**