feat(core,cli): add support for Gemma 4 models (experimental) (#25604)

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

@@ -3055,6 +3055,18 @@ describe('loadCliConfig gemmaModelRouter', () => {
     expect(gemmaSettings.classifier?.model).toBe('custom-gemma');
   });
 
+  it('should load experimental.gemma setting from merged settings', async () => {
+    process.argv = ['node', 'script.js'];
+    const argv = await parseArguments(createTestMergedSettings());
+    const settings = createTestMergedSettings({
+      experimental: {
+        gemma: true,
+      },
+    });
+    const config = await loadCliConfig(settings, 'test-session', argv);
+    expect(config.getExperimentalGemma()).toBe(true);
+  });
+
   it('should handle partial gemmaModelRouter settings', async () => {
     process.argv = ['node', 'script.js'];
     const argv = await parseArguments(createTestMergedSettings());

packages/cli/src/config/config.ts

@@ -1011,6 +1011,7 @@ export async function loadCliConfig(
     experimentalJitContext,
     experimentalMemoryV2: settings.experimental?.memoryV2,
     experimentalAutoMemory: settings.experimental?.autoMemory,
+    experimentalGemma: settings.experimental?.gemma,
     contextManagement,
     modelSteering: settings.experimental?.modelSteering,
     topicUpdateNarration:

packages/cli/src/config/settingsSchema.ts

@@ -2052,6 +2052,15 @@ const SETTINGS_SCHEMA = {
     description: 'Setting to enable experimental features',
     showInDialog: false,
     properties: {
+      gemma: {
+        type: 'boolean',
+        label: 'Gemma Models',
+        category: 'Experimental',
+        requiresRestart: true,
+        default: false,
+        description: 'Enable access to Gemma 4 models (experimental).',
+        showInDialog: true,
+      },
       adk: {
         type: 'object',
         label: 'ADK',