diff --git a/packages/vertexai/src/methods/chrome-adapter.test.ts b/packages/vertexai/src/methods/chrome-adapter.test.ts
index 859a02a4e85..330adc48e32 100644
--- a/packages/vertexai/src/methods/chrome-adapter.test.ts
+++ b/packages/vertexai/src/methods/chrome-adapter.test.ts
@@ -122,13 +122,14 @@ describe('ChromeAdapter', () => {
       const createStub = stub(languageModelProvider, 'create').resolves(
         {} as LanguageModel
       );
-      const adapter = new ChromeAdapter(
-        languageModelProvider,
-        'prefer_on_device'
-      );
       const expectedOnDeviceParams = {
         expectedInputs: [{ type: 'image' }]
       } as LanguageModelCreateOptions;
+      const adapter = new ChromeAdapter(
+        languageModelProvider,
+        'prefer_on_device',
+        expectedOnDeviceParams
+      );
       expect(
         await adapter.isAvailable({
           contents: [{ role: 'user', parts: [{ text: 'hi' }] }]
@@ -221,9 +222,6 @@ describe('ChromeAdapter', () => {
       );
       const promptOutput = 'hi';
       const promptStub = stub(languageModel, 'prompt').resolves(promptOutput);
-      const onDeviceParams = {
-        systemPrompt: 'be yourself'
-      } as LanguageModelCreateOptions;
       const expectedOnDeviceParams = {
         systemPrompt: 'be yourself',
         expectedInputs: [{ type: 'image' }]
@@ -231,7 +229,7 @@ describe('ChromeAdapter', () => {
       const adapter = new ChromeAdapter(
         languageModelProvider,
         'prefer_on_device',
-        onDeviceParams
+        expectedOnDeviceParams
       );
       const request = {
         contents: [{ role: 'user', parts: [{ text: 'anything' }] }]
@@ -270,9 +268,6 @@ describe('ChromeAdapter', () => {
       );
       const promptOutput = 'hi';
       const promptStub = stub(languageModel, 'prompt').resolves(promptOutput);
-      const onDeviceParams = {
-        systemPrompt: 'be yourself'
-      } as LanguageModelCreateOptions;
       const expectedOnDeviceParams = {
         systemPrompt: 'be yourself',
         expectedInputs: [{ type: 'image' }]
@@ -280,7 +275,7 @@ describe('ChromeAdapter', () => {
       const adapter = new ChromeAdapter(
         languageModelProvider,
         'prefer_on_device',
-        onDeviceParams
+        expectedOnDeviceParams
       );
       const request = {
         contents: [
@@ -379,14 +374,13 @@ describe('ChromeAdapter', () => {
           }
         })
       );
-      const onDeviceParams = {} as LanguageModelCreateOptions;
       const expectedOnDeviceParams = {
         expectedInputs: [{ type: 'image' }]
       } as LanguageModelCreateOptions;
       const adapter = new ChromeAdapter(
         languageModelProvider,
         'prefer_on_device',
-        onDeviceParams
+        expectedOnDeviceParams
       );
       const request = {
         contents: [{ role: 'user', parts: [{ text: 'anything' }] }]
@@ -423,14 +417,13 @@ describe('ChromeAdapter', () => {
           }
         })
       );
-      const onDeviceParams = {} as LanguageModelCreateOptions;
       const expectedOnDeviceParams = {
         expectedInputs: [{ type: 'image' }]
       } as LanguageModelCreateOptions;
       const adapter = new ChromeAdapter(
         languageModelProvider,
         'prefer_on_device',
-        onDeviceParams
+        expectedOnDeviceParams
       );
       const request = {
         contents: [
diff --git a/packages/vertexai/src/methods/chrome-adapter.ts b/packages/vertexai/src/methods/chrome-adapter.ts
index 32dec23035d..57a219f7041 100644
--- a/packages/vertexai/src/methods/chrome-adapter.ts
+++ b/packages/vertexai/src/methods/chrome-adapter.ts
@@ -42,9 +42,7 @@ export class ChromeAdapter {
     private languageModelProvider?: LanguageModel,
     private mode?: InferenceMode,
     private onDeviceParams: LanguageModelCreateOptions = {}
-  ) {
-    this.addImageTypeAsExpectedInput();
-  }
+  ) {}
 
   /**
    * Checks if a given request can be made on-device.
@@ -237,11 +235,6 @@ export class ChromeAdapter {
     return newSession;
   }
 
-  private addImageTypeAsExpectedInput(): void {
-    // Defaults to support image inputs for convenience.
-    this.onDeviceParams.expectedInputs ??= [{ type: 'image' }];
-  }
-
   /**
    * Formats string returned by Chrome as a {@link Response} returned by Vertex.
    */