feat: support appending request hints to prompt (#965)

app/(chat)/api/chat/route.ts

@@ -6,7 +6,7 @@ import {
   streamText,
 } from 'ai';
 import { auth, type UserType } from '@/app/(auth)/auth';
-import { systemPrompt } from '@/lib/ai/prompts';
+import { type RequestHints, systemPrompt } from '@/lib/ai/prompts';
 import {
   deleteChatById,
   getChatById,
@@ -25,6 +25,7 @@ import { isProductionEnvironment } from '@/lib/constants';
 import { myProvider } from '@/lib/ai/providers';
 import { entitlementsByUserType } from '@/lib/ai/entitlements';
 import { postRequestBodySchema, type PostRequestBody } from './schema';
+import { geolocation } from '@vercel/functions';
 
 export const maxDuration = 60;
 
@@ -85,6 +86,15 @@ export async function POST(request: Request) {
       message,
     });
 
+    const { longitude, latitude, city, country } = geolocation(request);
+
+    const requestHints: RequestHints = {
+      longitude,
+      latitude,
+      city,
+      country,
+    };
+
     await saveMessages({
       messages: [
         {
@@ -102,7 +112,7 @@ export async function POST(request: Request) {
       execute: (dataStream) => {
         const result = streamText({
           model: myProvider.languageModel(selectedChatModel),
-          system: systemPrompt({ selectedChatModel }),
+          system: systemPrompt({ selectedChatModel, requestHints }),
           messages,
           maxSteps: 5,
           experimental_activeTools: