feat (provider/google): support system instructions

.changeset/ninety-beers-do.md

@@ -0,0 +1,5 @@
+---
+'@ai-sdk/google': patch
+---
+
+feat (provider/google): support system instructions

content/providers/01-ai-sdk-providers/10-google-generative-ai.mdx

@@ -67,18 +67,18 @@ You can use the following optional settings to customize the Google Generative A
 ## Language Models
 
 You can create models that call the [Google Generative AI API](https://ai.google.dev/api/rest) using the provider instance.
-The first argument is the model id, e.g. `models/gemini-pro`.
+The first argument is the model id, e.g. `models/gemini-1.5-pro-latest`.
 The models support tool calls and some have multi-modal capabilities.
 
 ```ts
-const model = google('models/gemini-pro');
+const model = google('models/gemini-1.5-pro-latest');
 ```
 
 Google Generative AI models support also some model specific settings that are not part of the [standard call settings](/docs/ai-sdk-core/settings).
 You can pass them as an options argument:
 
 ```ts
-const model = google('models/gemini-pro', {
+const model = google('models/gemini-1.5-pro-latest', {
   topK: 0.2,
 });
 ```

examples/ai-core/src/generate-text/google-custom-fetch.ts

@@ -17,7 +17,7 @@ const google = createGoogleGenerativeAI({
 
 async function main() {
   const result = await generateText({
-    model: google('models/gemini-pro'),
+    model: google('models/gemini-1.5-pro-latest'),
     prompt: 'Invent a new holiday and describe its traditions.',
   });
 

examples/ai-core/src/generate-text/google-tool-call.ts

@@ -8,7 +8,7 @@ dotenv.config();
 
 async function main() {
   const result = await generateText({
-    model: google('models/gemini-pro'),
+    model: google('models/gemini-1.5-pro-latest'),
     maxTokens: 512,
     tools: {
       weather: weatherTool,

examples/ai-core/src/generate-text/google.ts

@@ -6,7 +6,7 @@ dotenv.config();
 
 async function main() {
   const result = await generateText({
-    model: google('models/gemini-pro'),
+    model: google('models/gemini-1.5-pro-latest'),
     prompt: 'Invent a new holiday and describe its traditions.',
   });
 

examples/ai-core/src/stream-text/google-chatbot-with-tools.ts

@@ -23,7 +23,7 @@ async function main() {
     }
 
     const result = await streamText({
-      model: google('models/gemini-pro'),
+      model: google('models/gemini-1.5-pro-latest'),
       tools: { weatherTool },
       system: `You are a helpful, respectful and honest assistant.`,
       messages,

examples/ai-core/src/stream-text/google-chatbot.ts

@@ -19,7 +19,7 @@ async function main() {
     messages.push({ role: 'user', content: userInput });
 
     const result = await streamText({
-      model: google('models/gemini-pro'),
+      model: google('models/gemini-1.5-pro-latest'),
       system: `You are a helpful, respectful and honest assistant.`,
       messages,
     });

examples/ai-core/src/stream-text/google-fullstream.ts

@@ -8,7 +8,7 @@ dotenv.config();
 
 async function main() {
   const result = await streamText({
-    model: google('models/gemini-pro'),
+    model: google('models/gemini-1.5-pro-latest'),
     tools: {
       weather: weatherTool,
       cityAttractions: {

examples/ai-core/src/stream-text/google.ts

@@ -6,7 +6,8 @@ dotenv.config();
 
 async function main() {
   const result = await streamText({
-    model: google('models/gemini-pro'),
+    model: google('models/gemini-1.5-pro-latest'),
+    system: 'You are a comedian. Only give funny answers.',
     prompt: 'Invent a new holiday and describe its traditions.',
   });
 

packages/google/README.md

@@ -25,7 +25,7 @@ import { google } from '@ai-sdk/google';
 import { generateText } from 'ai';
 
 const { text } = await generateText({
-  model: google('models/gemini-1.5-flash-latest'),
+  model: google('models/gemini-1.5-pro-latest'),
   prompt: 'Write a vegetarian lasagna recipe for 4 people.',
 });
 ```

packages/google/src/convert-to-google-generative-ai-messages.test.ts

@@ -1,5 +1,31 @@
 import { convertToGoogleGenerativeAIMessages } from './convert-to-google-generative-ai-messages';
 
+describe('system messages', () => {
+  it('should store system message in system instruction', async () => {
+    const result = await convertToGoogleGenerativeAIMessages({
+      prompt: [{ role: 'system', content: 'Test' }],
+    });
+
+    expect(result).toEqual({
+      systemInstruction: { parts: [{ text: 'Test' }] },
+      contents: [],
+    });
+  });
+
+  it('should throw error when there was already a user message', async () => {
+    await expect(
+      convertToGoogleGenerativeAIMessages({
+        prompt: [
+          { role: 'user', content: [{ type: 'text', text: 'Test' }] },
+          { role: 'system', content: 'Test' },
+        ],
+      }),
+    ).rejects.toThrow(
+      'system messages are only supported at the beginning of the conversation',
+    );
+  });
+});
+
 describe('user messages', () => {
   it('should download images for user image parts with URLs', async () => {
     const result = await convertToGoogleGenerativeAIMessages({
@@ -24,19 +50,22 @@ describe('user messages', () => {
       },
     });
 
-    expect(result).toEqual([
-      {
-        role: 'user',
-        parts: [
-          {
-            inlineData: {
-              data: 'AAECAw==',
-              mimeType: 'image/png',
+    expect(result).toEqual({
+      systemInstruction: undefined,
+      contents: [
+        {
+          role: 'user',
+          parts: [
+            {
+              inlineData: {
+                data: 'AAECAw==',
+                mimeType: 'image/png',
+              },
             },
-          },
-        ],
-      },
-    ]);
+          ],
+        },
+      ],
+    });
   });
 
   it('should add image parts for UInt8Array images', async () => {
@@ -54,23 +83,26 @@ describe('user messages', () => {
         },
       ],
 
-      downloadImplementation: async ({ url }) => {
+      downloadImplementation: async () => {
         throw new Error('Unexpected download call');
       },
     });
 
-    expect(result).toEqual([
-      {
-        role: 'user',
-        parts: [
-          {
-            inlineData: {
-              data: 'AAECAw==',
-              mimeType: 'image/png',
+    expect(result).toEqual({
+      systemInstruction: undefined,
+      contents: [
+        {
+          role: 'user',
+          parts: [
+            {
+              inlineData: {
+                data: 'AAECAw==',
+                mimeType: 'image/png',
+              },
             },
-          },
-        ],
-      },
-    ]);
+          ],
+        },
+      ],
+    });
   });
 });

packages/google/src/convert-to-google-generative-ai-messages.ts

@@ -1,6 +1,10 @@
-import { LanguageModelV1Prompt } from '@ai-sdk/provider';
+import {
+  LanguageModelV1Prompt,
+  UnsupportedFunctionalityError,
+} from '@ai-sdk/provider';
 import { convertUint8ArrayToBase64, download } from '@ai-sdk/provider-utils';
 import {
+  GoogleGenerativeAIContent,
   GoogleGenerativeAIContentPart,
   GoogleGenerativeAIPrompt,
 } from './google-generative-ai-prompt';
@@ -12,21 +16,27 @@ export async function convertToGoogleGenerativeAIMessages({
   prompt: LanguageModelV1Prompt;
   downloadImplementation?: typeof download;
 }): Promise<GoogleGenerativeAIPrompt> {
-  const messages: GoogleGenerativeAIPrompt = [];
+  const systemInstructionParts: Array<{ text: string }> = [];
+  const contents: Array<GoogleGenerativeAIContent> = [];
+  let systemMessagesAllowed = true;
 
   for (const { role, content } of prompt) {
     switch (role) {
       case 'system': {
-        // system message becomes user message:
-        messages.push({ role: 'user', parts: [{ text: content }] });
-
-        // required for to ensure turn-taking:
-        messages.push({ role: 'model', parts: [{ text: '' }] });
+        if (!systemMessagesAllowed) {
+          throw new UnsupportedFunctionalityError({
+            functionality:
+              'system messages are only supported at the beginning of the conversation',
+          });
+        }
 
+        systemInstructionParts.push({ text: content });
         break;
       }
 
       case 'user': {
+        systemMessagesAllowed = false;
+
         const parts: GoogleGenerativeAIContentPart[] = [];
 
         for (const part of content) {
@@ -63,12 +73,14 @@ export async function convertToGoogleGenerativeAIMessages({
           }
         }
 
-        messages.push({ role: 'user', parts });
+        contents.push({ role: 'user', parts });
         break;
       }
 
       case 'assistant': {
-        messages.push({
+        systemMessagesAllowed = false;
+
+        contents.push({
           role: 'model',
           parts: content
             .map(part => {
@@ -96,7 +108,9 @@ export async function convertToGoogleGenerativeAIMessages({
       }
 
       case 'tool': {
-        messages.push({
+        systemMessagesAllowed = false;
+
+        contents.push({
           role: 'user',
           parts: content.map(part => ({
             functionResponse: {
@@ -114,5 +128,11 @@ export async function convertToGoogleGenerativeAIMessages({
     }
   }
 
-  return messages;
+  return {
+    systemInstruction:
+      systemInstructionParts.length > 0
+        ? { parts: systemInstructionParts }
+        : undefined,
+    contents,
+  };
 }

packages/google/src/google-generative-ai-language-model.test.ts

@@ -207,7 +207,10 @@ describe('doGenerate', () => {
       await model.doGenerate({
         inputFormat: 'prompt',
         mode: { type: 'regular' },
-        prompt: TEST_PROMPT,
+        prompt: [
+          { role: 'system', content: 'test system instruction' },
+          { role: 'user', content: [{ type: 'text', text: 'Hello' }] },
+        ],
       });
 
       expect(await call(0).getRequestBodyJson()).toStrictEqual({
@@ -217,6 +220,7 @@ describe('doGenerate', () => {
             parts: [{ text: 'Hello' }],
           },
         ],
+        systemInstruction: { parts: [{ text: 'test system instruction' }] },
         generationConfig: {},
       });
     }),

packages/google/src/google-generative-ai-language-model.ts

@@ -98,14 +98,16 @@ export class GoogleGenerativeAILanguageModel implements LanguageModelV1 {
       topP,
     };
 
-    const contents = await convertToGoogleGenerativeAIMessages({ prompt });
+    const { contents, systemInstruction } =
+      await convertToGoogleGenerativeAIMessages({ prompt });
 
     switch (type) {
       case 'regular': {
         return {
           args: {
             generationConfig,
             contents,
+            systemInstruction,
             safetySettings: this.settings.safetySettings,
             ...prepareToolsAndToolConfig(mode),
           },
@@ -121,6 +123,7 @@ export class GoogleGenerativeAILanguageModel implements LanguageModelV1 {
               response_mime_type: 'application/json',
             },
             contents,
+            systemInstruction,
             safetySettings: this.settings.safetySettings,
           },
           warnings,

packages/google/src/google-generative-ai-prompt.ts

@@ -1,4 +1,11 @@
-export type GoogleGenerativeAIPrompt = Array<GoogleGenerativeAIContent>;
+export type GoogleGenerativeAIPrompt = {
+  systemInstruction?: GoogleGenerativeAISystemInstruction;
+  contents: Array<GoogleGenerativeAIContent>;
+};
+
+export type GoogleGenerativeAISystemInstruction = {
+  parts: Array<{ text: string }>;
+};
 
 export type GoogleGenerativeAIContent = {
   role: 'user' | 'model';