Configurable thinking budget (default to medium) (#494)

e2e-tests/snapshots/context_manage.spec.ts_manage-context---smart-context---auto-includes-only-1.txt

@@ -16,7 +16,8 @@
     "stream": true,
     "thinking": {
       "type": "enabled",
-      "include_thoughts": true
+      "include_thoughts": true,
+      "budget_tokens": 4000
     },
     "dyad_options": {
       "files": [

e2e-tests/snapshots/context_manage.spec.ts_manage-context---smart-context-1.txt

@@ -16,7 +16,8 @@
     "stream": true,
     "thinking": {
       "type": "enabled",
-      "include_thoughts": true
+      "include_thoughts": true,
+      "budget_tokens": 4000
     },
     "dyad_options": {
       "files": [

e2e-tests/snapshots/context_manage.spec.ts_manage-context---smart-context-3.txt

@@ -24,7 +24,8 @@
     "stream": true,
     "thinking": {
       "type": "enabled",
-      "include_thoughts": true
+      "include_thoughts": true,
+      "budget_tokens": 4000
     },
     "dyad_options": {
       "files": [

e2e-tests/snapshots/context_manage.spec.ts_manage-context---smart-context-4.txt

@@ -32,7 +32,8 @@
     "stream": true,
     "thinking": {
       "type": "enabled",
-      "include_thoughts": true
+      "include_thoughts": true,
+      "budget_tokens": 4000
     },
     "dyad_options": {
       "files": [

e2e-tests/snapshots/engine.spec.ts_regular-auto-should-send-message-to-engine-1.txt

@@ -16,7 +16,8 @@
     "stream": true,
     "thinking": {
       "type": "enabled",
-      "include_thoughts": true
+      "include_thoughts": true,
+      "budget_tokens": 4000
     },
     "dyad_options": {
       "files": [

e2e-tests/snapshots/engine.spec.ts_send-message-to-engine-1.txt

@@ -16,7 +16,8 @@
     "stream": true,
     "thinking": {
       "type": "enabled",
-      "include_thoughts": true
+      "include_thoughts": true,
+      "budget_tokens": 4000
     },
     "dyad_options": {
       "files": [

e2e-tests/snapshots/engine.spec.ts_smart-auto-should-send-message-to-engine-1.txt

@@ -16,7 +16,8 @@
     "stream": true,
     "thinking": {
       "type": "enabled",
-      "include_thoughts": true
+      "include_thoughts": true,
+      "budget_tokens": 4000
     },
     "dyad_options": {
       "files": [

e2e-tests/snapshots/thinking_budget.spec.ts_thinking-budget-1.txt

+{
+  "selectedModel": {
+    "name": "gemini-2.5-pro",
+    "provider": "google"
+  },
+  "providerSettings": {
+    "auto": {
+      "apiKey": {
+        "value": "testdyadkey",
+        "encryptionType": "plaintext"
+      }
+    }
+  },
+  "telemetryConsent": "unset",
+  "telemetryUserId": "[UUID]",
+  "hasRunBefore": true,
+  "enableDyadPro": true,
+  "experiments": {},
+  "lastShownReleaseNotesVersion": "[scrubbed]",
+  "thinkingBudget": "low",
+  "enableProLazyEditsMode": true,
+  "enableProSmartFilesContextMode": true,
+  "selectedChatMode": "build",
+  "isTestMode": true
+}
\ No newline at end of file

e2e-tests/snapshots/thinking_budget.spec.ts_thinking-budget-3.txt

+{
+  "selectedModel": {
+    "name": "gemini-2.5-pro",
+    "provider": "google"
+  },
+  "providerSettings": {
+    "auto": {
+      "apiKey": {
+        "value": "testdyadkey",
+        "encryptionType": "plaintext"
+      }
+    }
+  },
+  "telemetryConsent": "unset",
+  "telemetryUserId": "[UUID]",
+  "hasRunBefore": true,
+  "enableDyadPro": true,
+  "experiments": {},
+  "lastShownReleaseNotesVersion": "[scrubbed]",
+  "thinkingBudget": "medium",
+  "enableProLazyEditsMode": true,
+  "enableProSmartFilesContextMode": true,
+  "selectedChatMode": "build",
+  "isTestMode": true
+}
\ No newline at end of file

e2e-tests/snapshots/thinking_budget.spec.ts_thinking-budget-5.txt

+{
+  "selectedModel": {
+    "name": "gemini-2.5-pro",
+    "provider": "google"
+  },
+  "providerSettings": {
+    "auto": {
+      "apiKey": {
+        "value": "testdyadkey",
+        "encryptionType": "plaintext"
+      }
+    }
+  },
+  "telemetryConsent": "unset",
+  "telemetryUserId": "[UUID]",
+  "hasRunBefore": true,
+  "enableDyadPro": true,
+  "experiments": {},
+  "lastShownReleaseNotesVersion": "[scrubbed]",
+  "thinkingBudget": "high",
+  "enableProLazyEditsMode": true,
+  "enableProSmartFilesContextMode": true,
+  "selectedChatMode": "build",
+  "isTestMode": true
+}
\ No newline at end of file

e2e-tests/thinking_budget.spec.ts

+import { testSkipIfWindows } from "./helpers/test_helper";
+
+testSkipIfWindows("thinking budget", async ({ po }) => {
+  await po.setUpDyadPro();
+  await po.selectModel({ provider: "Google", model: "Gemini 2.5 Pro" });
+  await po.sendPrompt("tc=1");
+
+  // Low
+  await po.goToSettingsTab();
+  await po.page.getByRole("combobox", { name: "Thinking Budget" }).click();
+  await po.page.getByRole("option", { name: "Low" }).click();
+  await po.snapshotSettings();
+  await po.page.getByText("Go Back").click();
+  await po.sendPrompt("[dump] hi");
+  await po.snapshotServerDump("request");
+
+  // Medium
+  await po.goToSettingsTab();
+  await po.page.getByRole("combobox", { name: "Thinking Budget" }).click();
+  await po.page.getByRole("option", { name: "Medium (default)" }).click();
+  await po.snapshotSettings();
+  await po.page.getByText("Go Back").click();
+  await po.sendPrompt("[dump] hi");
+  await po.snapshotServerDump("request");
+
+  // High
+  await po.goToSettingsTab();
+  await po.page.getByRole("combobox", { name: "Thinking Budget" }).click();
+  await po.page.getByRole("option", { name: "High" }).click();
+  await po.snapshotSettings();
+  await po.page.getByText("Go Back").click();
+  await po.sendPrompt("[dump] hi");
+  await po.snapshotServerDump("request");
+});

src/components/ThinkingBudgetSelector.tsx

+import React from "react";
+import { useSettings } from "@/hooks/useSettings";
+import {
+  Select,
+  SelectContent,
+  SelectItem,
+  SelectTrigger,
+  SelectValue,
+} from "@/components/ui/select";
+
+interface OptionInfo {
+  value: string;
+  label: string;
+  description: string;
+}
+
+const defaultValue = "medium";
+
+const options: OptionInfo[] = [
+  {
+    value: "low",
+    label: "Low",
+    description:
+      "Minimal thinking tokens for faster responses and lower costs.",
+  },
+  {
+    value: defaultValue,
+    label: "Medium (default)",
+    description: "Balanced thinking for most conversations.",
+  },
+  {
+    value: "high",
+    label: "High",
+    description:
+      "Extended thinking for complex problems requiring deep analysis.",
+  },
+];
+
+export const ThinkingBudgetSelector: React.FC = () => {
+  const { settings, updateSettings } = useSettings();
+
+  const handleValueChange = (value: string) => {
+    updateSettings({ thinkingBudget: value as "low" | "medium" | "high" });
+  };
+
+  // Determine the current value
+  const currentValue = settings?.thinkingBudget || defaultValue;
+
+  // Find the current option to display its description
+  const currentOption =
+    options.find((opt) => opt.value === currentValue) || options[1];
+
+  return (
+    <div className="space-y-1">
+      <div className="flex items-center gap-4">
+        <label
+          htmlFor="thinking-budget"
+          className="text-sm font-medium text-gray-700 dark:text-gray-300"
+        >
+          Thinking Budget
+        </label>
+        <Select value={currentValue} onValueChange={handleValueChange}>
+          <SelectTrigger className="w-[180px]" id="thinking-budget">
+            <SelectValue placeholder="Select budget" />
+          </SelectTrigger>
+          <SelectContent>
+            {options.map((option) => (
+              <SelectItem key={option.value} value={option.value}>
+                {option.label}
+              </SelectItem>
+            ))}
+          </SelectContent>
+        </Select>
+      </div>
+      <div className="text-sm text-gray-500 dark:text-gray-400">
+        {currentOption.description}
+      </div>
+    </div>
+  );
+};

src/ipc/handlers/chat_stream_handlers.ts

@@ -464,6 +464,7 @@ This conversation includes one or more image attachments. When the user uploads
             providerOptions: {
               "dyad-gateway": getExtraProviderOptions(
                 modelClient.builtinProviderId,
+                settings,
               ),
               google: {
                 thinkingConfig: {

src/ipc/utils/get_model_client.ts

@@ -84,6 +84,7 @@ export async function getModelClient(
                   : settings.enableProLazyEditsMode,
               enableSmartFilesContext: settings.enableProSmartFilesContextMode,
             },
+            settings,
           })
         : createOpenAICompatible({
             name: "dyad-gateway",

src/ipc/utils/llm_engine_provider.ts

@@ -12,6 +12,7 @@ import {
 import { OpenAICompatibleChatSettings } from "@ai-sdk/openai-compatible";
 import log from "electron-log";
 import { getExtraProviderOptions } from "./thinking_utils";
+import type { UserSettings } from "../../lib/schemas";
 
 const logger = log.scope("llm_engine_provider");
 
@@ -48,6 +49,7 @@ or to provide a custom fetch implementation for e.g. testing.
     enableLazyEdits?: boolean;
     enableSmartFilesContext?: boolean;
   };
+  settings: UserSettings;
 }
 
 export interface DyadEngineProvider {
@@ -125,7 +127,10 @@ export function createDyadEngine(
           // Parse the request body to manipulate it
           const parsedBody = {
             ...JSON.parse(init.body),
-            ...getExtraProviderOptions(options.originalProviderId),
+            ...getExtraProviderOptions(
+              options.originalProviderId,
+              options.settings,
+            ),
           };
 
           // Add files to the request if they exist

src/ipc/utils/thinking_utils.ts

 import { PROVIDERS_THAT_SUPPORT_THINKING } from "../shared/language_model_helpers";
+import type { UserSettings } from "../../lib/schemas";
+
+function getThinkingBudgetTokens(
+  thinkingBudget?: "low" | "medium" | "high",
+): number {
+  switch (thinkingBudget) {
+    case "low":
+      return 1_000;
+    case "medium":
+      return 4_000;
+    case "high":
+      return -1;
+    default:
+      return 4_000; // Default to medium
+  }
+}
 
 export function getExtraProviderOptions(
   providerId: string | undefined,
+  settings: UserSettings,
 ): Record<string, any> {
   if (!providerId) {
     return {};
   }
   if (PROVIDERS_THAT_SUPPORT_THINKING.includes(providerId)) {
+    const budgetTokens = getThinkingBudgetTokens(settings?.thinkingBudget);
     return {
       thinking: {
         type: "enabled",
         include_thoughts: true,
+        // -1 means dynamic thinking where model determines.
+        // budget_tokens: 128, // minimum for Gemini Pro is 128
+        budget_tokens: budgetTokens,
       },
     };
   }

src/lib/schemas.ts

@@ -142,6 +142,7 @@ export const UserSettingsSchema = z.object({
   experiments: ExperimentsSchema.optional(),
   lastShownReleaseNotesVersion: z.string().optional(),
   maxChatTurnsInContext: z.number().optional(),
+  thinkingBudget: z.enum(["low", "medium", "high"]).optional(),
   enableProLazyEditsMode: z.boolean().optional(),
   enableProSmartFilesContextMode: z.boolean().optional(),
   selectedTemplateId: z.string().optional(),

src/pages/settings.tsx

@@ -7,6 +7,7 @@ import { showSuccess, showError } from "@/lib/toast";
 import { AutoApproveSwitch } from "@/components/AutoApproveSwitch";
 import { TelemetrySwitch } from "@/components/TelemetrySwitch";
 import { MaxChatTurnsSelector } from "@/components/MaxChatTurnsSelector";
+import { ThinkingBudgetSelector } from "@/components/ThinkingBudgetSelector";
 import { useSettings } from "@/hooks/useSettings";
 import { useAppVersion } from "@/hooks/useAppVersion";
 import { Button } from "@/components/ui/button";
@@ -138,6 +139,10 @@ export default function SettingsPage() {
               </div>
             </div>
 
+            <div className="mt-4">
+              <ThinkingBudgetSelector />
+            </div>
+
             <div className="mt-4">
               <MaxChatTurnsSelector />
             </div>