Problems: auto-fix & problem panel (#541)

e2e-tests/fixtures/create-ts-errors-complex.md

+Tests delete-rename-write order
+<dyad-delete path="src/main.tsx">
+</dyad-delete>
+<dyad-rename from="src/App.tsx" to="src/main.tsx">
+</dyad-rename>
+<dyad-write path="src/main.tsx" description="final main.tsx file.">
+finalMainTsxFileWithError();
+</dyad-write>
+EOM

e2e-tests/fixtures/create-ts-errors.md

+This will get a TypeScript error.
+
+<dyad-write path="src/bad-file.ts" description="This will get a TypeScript error.">
+import NonExistentClass from 'non-existent-class';
+
+const x = new Object();
+x.nonExistentMethod();
+</dyad-write>
+
+EOM

e2e-tests/fixtures/create-unfixable-ts-errors.md

+This should not get fixed
+
+<dyad-write path="src/bad-file.ts" description="This will produce 5 TypeScript errors.">
+import NonExistentClass from 'non-existent-class';
+import NonExistentClass2 from 'non-existent-class';
+import NonExistentClass3 from 'non-existent-class';
+import NonExistentClass4 from 'non-existent-class';
+import NonExistentClass5 from 'non-existent-class';
+</dyad-write>
+
+EOM

e2e-tests/helpers/test_helper.ts

@@ -205,7 +205,12 @@ export class PageObject {
   async setUp({
     autoApprove = false,
     nativeGit = false,
-  }: { autoApprove?: boolean; nativeGit?: boolean } = {}) {
+    disableAutoFixProblems = false,
+  }: {
+    autoApprove?: boolean;
+    nativeGit?: boolean;
+    disableAutoFixProblems?: boolean;
+  } = {}) {
     await this.baseSetup();
     await this.goToSettingsTab();
     if (autoApprove) {
@@ -214,6 +219,9 @@ export class PageObject {
     if (nativeGit) {
       await this.toggleNativeGit();
     }
+    if (disableAutoFixProblems) {
+      await this.toggleAutoFixProblems();
+    }
     await this.setUpTestProvider();
     await this.setUpTestModel();
 
@@ -231,6 +239,61 @@ export class PageObject {
     await this.goToAppsTab();
   }
 
+  async runPnpmInstall() {
+    const appPath = await this.getCurrentAppPath();
+    if (!appPath) {
+      throw new Error("No app selected");
+    }
+
+    const maxRetries = 3;
+    let lastError: any;
+
+    for (let attempt = 1; attempt <= maxRetries; attempt++) {
+      try {
+        console.log(
+          `Running 'pnpm install' in ${appPath} (attempt ${attempt}/${maxRetries})`,
+        );
+        execSync("pnpm install", {
+          cwd: appPath,
+          stdio: "pipe",
+          encoding: "utf8",
+        });
+        console.log(`'pnpm install' succeeded on attempt ${attempt}`);
+        return; // Success, exit the function
+      } catch (error: any) {
+        lastError = error;
+        console.error(
+          `Attempt ${attempt}/${maxRetries} failed to run 'pnpm install' in ${appPath}`,
+        );
+        console.error(`Exit code: ${error.status}`);
+        console.error(`Command: ${error.cmd || "pnpm install"}`);
+
+        if (error.stdout) {
+          console.error(`STDOUT:\n${error.stdout}`);
+        }
+
+        if (error.stderr) {
+          console.error(`STDERR:\n${error.stderr}`);
+        }
+
+        // If this wasn't the last attempt, wait a bit before retrying
+        if (attempt < maxRetries) {
+          const delayMs = 1000 * attempt; // Exponential backoff: 1s, 2s
+          console.log(`Waiting ${delayMs}ms before retry...`);
+          await new Promise((resolve) => setTimeout(resolve, delayMs));
+        }
+      }
+    }
+
+    // All attempts failed, throw the last error with enhanced message
+    throw new Error(
+      `pnpm install failed in ${appPath} after ${maxRetries} attempts. ` +
+        `Exit code: ${lastError.status}. ` +
+        `${lastError.stderr ? `Error: ${lastError.stderr}` : ""}` +
+        `${lastError.stdout ? ` Output: ${lastError.stdout}` : ""}`,
+    );
+  }
+
   async setUpDyadProvider() {
     await this.page
       .locator("div")
@@ -335,7 +398,7 @@ export class PageObject {
           throw new Error("Messages list not found");
         }
         messagesList.innerHTML = messagesList.innerHTML.replace(
-          /\[\[dyad-dump-path=([^\]]+)\]\]/,
+          /\[\[dyad-dump-path=([^\]]+)\]\]/g,
           "[[dyad-dump-path=*]]",
         );
       });
@@ -355,6 +418,27 @@ export class PageObject {
     await this.page.getByRole("button", { name: "Restart" }).click();
   }
 
+  ////////////////////////////////
+  // Preview panel
+  ////////////////////////////////
+
+  async selectPreviewMode(mode: "code" | "problems" | "preview") {
+    await this.page.getByTestId(`${mode}-mode-button`).click();
+  }
+
+  async clickRecheckProblems() {
+    await this.page.getByTestId("recheck-button").click();
+  }
+
+  async clickFixAllProblems() {
+    await this.page.getByTestId("fix-all-button").click();
+    await this.waitForChatCompletion();
+  }
+
+  async snapshotProblemsPane() {
+    await expect(this.page.getByTestId("problems-pane")).toMatchAriaSnapshot();
+  }
+
   async clickRebuild() {
     await this.clickPreviewMoreOptions();
     await this.page.getByText("Rebuild").click();
@@ -402,6 +486,12 @@ export class PageObject {
     return this.page.getByTestId("preview-iframe-element");
   }
 
+  expectPreviewIframeIsVisible() {
+    return expect(this.getPreviewIframeElement()).toBeVisible({
+      timeout: Timeout.LONG,
+    });
+  }
+
   async clickFixErrorWithAI() {
     await this.page.getByRole("button", { name: "Fix error with AI" }).click();
   }
@@ -438,23 +528,46 @@ export class PageObject {
 
   async snapshotServerDump(
     type: "all-messages" | "last-message" | "request" = "all-messages",
-    { name = "" }: { name?: string } = {},
+    { name = "", dumpIndex = -1 }: { name?: string; dumpIndex?: number } = {},
   ) {
     // Get the text content of the messages list
     const messagesListText = await this.page
       .getByTestId("messages-list")
       .textContent();
 
-    // Find the dump path using regex
-    const dumpPathMatch = messagesListText?.match(
-      /.*\[\[dyad-dump-path=([^\]]+)\]\]/,
+    // Find ALL dump paths using global regex
+    const dumpPathMatches = messagesListText?.match(
+      /\[\[dyad-dump-path=([^\]]+)\]\]/g,
     );
 
-    if (!dumpPathMatch) {
+    if (!dumpPathMatches || dumpPathMatches.length === 0) {
       throw new Error("No dump path found in messages list");
     }
 
-    const dumpFilePath = dumpPathMatch[1];
+    // Extract the actual paths from the matches
+    const dumpPaths = dumpPathMatches
+      .map((match) => {
+        const pathMatch = match.match(/\[\[dyad-dump-path=([^\]]+)\]\]/);
+        return pathMatch ? pathMatch[1] : null;
+      })
+      .filter(Boolean);
+
+    // Select the dump path based on index
+    // -1 means last, -2 means second to last, etc.
+    // 0 means first, 1 means second, etc.
+    const selectedIndex =
+      dumpIndex < 0 ? dumpPaths.length + dumpIndex : dumpIndex;
+
+    if (selectedIndex < 0 || selectedIndex >= dumpPaths.length) {
+      throw new Error(
+        `Dump index ${dumpIndex} is out of range. Found ${dumpPaths.length} dump paths.`,
+      );
+    }
+
+    const dumpFilePath = dumpPaths[selectedIndex];
+    if (!dumpFilePath) {
+      throw new Error("No dump file path found");
+    }
 
     // Read the JSON file
     const dumpContent: string = (
@@ -701,6 +814,10 @@ export class PageObject {
     await this.page.getByRole("switch", { name: "Enable Native Git" }).click();
   }
 
+  async toggleAutoFixProblems() {
+    await this.page.getByRole("switch", { name: "Auto-fix problems" }).click();
+  }
+
   async snapshotSettings() {
     const settings = path.join(this.userDataDir, "user-settings.json");
     const settingsContent = fs.readFileSync(settings, "utf-8");
@@ -740,10 +857,16 @@ export class PageObject {
     await this.page.getByRole("link", { name: "Hub" }).click();
   }
 
-  async selectTemplate(templateName: string) {
+  private async selectTemplate(templateName: string) {
     await this.page.getByRole("img", { name: templateName }).click();
   }
 
+  async selectHubTemplate(templateName: "Next.js Template") {
+    await this.goToHubTab();
+    await this.selectTemplate(templateName);
+    await this.goToAppsTab();
+  }
+
   ////////////////////////////////
   // Toast assertions
   ////////////////////////////////

e2e-tests/problems.spec.ts

+import { test, testSkipIfWindows } from "./helpers/test_helper";
+import { expect } from "@playwright/test";
+import fs from "fs";
+import path from "path";
+
+const MINIMAL_APP = "minimal-with-ai-rules";
+
+testSkipIfWindows("problems auto-fix - enabled", async ({ po }) => {
+  await po.setUp();
+  await po.importApp(MINIMAL_APP);
+  await po.expectPreviewIframeIsVisible();
+
+  await po.sendPrompt("tc=create-ts-errors");
+
+  await po.snapshotServerDump("all-messages", { dumpIndex: -2 });
+  await po.snapshotServerDump("all-messages", { dumpIndex: -1 });
+
+  await po.snapshotMessages({ replaceDumpPath: true });
+});
+
+testSkipIfWindows(
+  "problems auto-fix - gives up after 2 attempts",
+  async ({ po }) => {
+    await po.setUp();
+    await po.importApp(MINIMAL_APP);
+    await po.expectPreviewIframeIsVisible();
+
+    await po.sendPrompt("tc=create-unfixable-ts-errors");
+
+    await po.snapshotServerDump("all-messages", { dumpIndex: -2 });
+    await po.snapshotServerDump("all-messages", { dumpIndex: -1 });
+
+    await po.page.getByTestId("problem-summary").last().click();
+    await expect(
+      po.page.getByTestId("problem-summary").last(),
+    ).toMatchAriaSnapshot();
+    await po.snapshotMessages({ replaceDumpPath: true });
+  },
+);
+
+testSkipIfWindows(
+  "problems auto-fix - complex delete-rename-write",
+  async ({ po }) => {
+    await po.setUp();
+    await po.importApp(MINIMAL_APP);
+    await po.expectPreviewIframeIsVisible();
+
+    await po.sendPrompt("tc=create-ts-errors-complex");
+
+    await po.snapshotServerDump("all-messages", { dumpIndex: -2 });
+    await po.snapshotServerDump("all-messages", { dumpIndex: -1 });
+
+    await po.snapshotMessages({ replaceDumpPath: true });
+  },
+);
+
+test("problems auto-fix - disabled", async ({ po }) => {
+  await po.setUp({ disableAutoFixProblems: true });
+  await po.importApp(MINIMAL_APP);
+  await po.expectPreviewIframeIsVisible();
+
+  await po.sendPrompt("tc=create-ts-errors");
+
+  await po.snapshotMessages();
+});
+
+test("problems - fix all", async ({ po }) => {
+  await po.setUp({ disableAutoFixProblems: true });
+  await po.importApp(MINIMAL_APP);
+  const appPath = await po.getCurrentAppPath();
+  const badFilePath = path.join(appPath, "src", "bad-file.tsx");
+  fs.writeFileSync(
+    badFilePath,
+    `const App = () => <div>Minimal imported app</div>;
+nonExistentFunction1();
+nonExistentFunction2();
+nonExistentFunction3();
+
+export default App;
+`,
+  );
+  await po.runPnpmInstall();
+
+  await po.sendPrompt("tc=create-ts-errors");
+  await po.selectPreviewMode("problems");
+  await po.clickFixAllProblems();
+
+  await po.snapshotServerDump("last-message");
+  await po.snapshotMessages({ replaceDumpPath: true });
+});
+
+test("problems - manual edit (react/vite)", async ({ po }) => {
+  await po.setUp();
+  await po.sendPrompt("tc=1");
+
+  const appPath = await po.getCurrentAppPath();
+  const badFilePath = path.join(appPath, "src", "bad-file.tsx");
+  fs.writeFileSync(
+    badFilePath,
+    `const App = () => <div>Minimal imported app</div>;
+nonExistentFunction();    
+
+export default App;
+`,
+  );
+  await po.runPnpmInstall();
+  await po.clickTogglePreviewPanel();
+
+  await po.selectPreviewMode("problems");
+  await po.clickRecheckProblems();
+  await po.snapshotProblemsPane();
+
+  fs.unlinkSync(badFilePath);
+
+  await po.clickRecheckProblems();
+  await po.snapshotProblemsPane();
+});
+
+test("problems - manual edit (next.js)", async ({ po }) => {
+  await po.setUp();
+  await po.selectHubTemplate("Next.js Template");
+  await po.sendPrompt("tc=1");
+
+  const appPath = await po.getCurrentAppPath();
+  const badFilePath = path.join(appPath, "src", "bad-file.tsx");
+  fs.writeFileSync(
+    badFilePath,
+    `const App = () => <div>Minimal imported app</div>;
+  nonExistentFunction();    
+  
+  export default App;
+  `,
+  );
+  await po.runPnpmInstall();
+  await po.clickTogglePreviewPanel();
+
+  await po.selectPreviewMode("problems");
+  await po.clickRecheckProblems();
+  await po.snapshotProblemsPane();
+
+  fs.unlinkSync(badFilePath);
+
+  await po.clickRecheckProblems();
+  await po.snapshotProblemsPane();
+});

e2e-tests/select_component.spec.ts

@@ -81,10 +81,7 @@ testSkipIfWindows("upgrade app to select component", async ({ po }) => {
 testSkipIfWindows("select component next.js", async ({ po }) => {
   await po.setUp();
 
-  // Select Next.js template
-  await po.goToHubTab();
-  await po.selectTemplate("Next.js Template");
-  await po.goToAppsTab();
+  await po.selectHubTemplate("Next.js Template");
 
   await po.sendPrompt("tc=basic");
   await po.clickTogglePreviewPanel();

e2e-tests/snapshots/context_window.spec.ts_context-window-4.txt

@@ -14,5 +14,6 @@
   "enableProLazyEditsMode": true,
   "enableProSmartFilesContextMode": true,
   "selectedChatMode": "build",
+  "enableAutoFixProblems": true,
   "isTestMode": true
 }
\ No newline at end of file

e2e-tests/snapshots/problems.spec.ts_problems---fix-all-1.aria.yml

+- paragraph: tc=create-ts-errors
+- paragraph: This will get a TypeScript error.
+- img
+- text: bad-file.ts
+- img
+- text: "src/bad-file.ts Summary: This will get a TypeScript error."
+- paragraph: EOM
+- paragraph: "Fix these 3 TypeScript compile-time errors:"
+- list:
+  - listitem: src/bad-file.tsx:2:1 - Cannot find name 'nonExistentFunction1'. (TS2304)
+  - listitem: src/bad-file.tsx:3:1 - Cannot find name 'nonExistentFunction2'. (TS2304)
+  - listitem: src/bad-file.tsx:4:1 - Cannot find name 'nonExistentFunction3'. (TS2304)
+- paragraph: Please fix all errors in a concise way.
+- img
+- text: file1.txt
+- img
+- text: file1.txt
+- paragraph: More EOM
+- paragraph: "[[dyad-dump-path=*]]"
+- button "Retry":
+  - img
\ No newline at end of file

e2e-tests/snapshots/problems.spec.ts_problems---fix-all-1.txt

+===
+role: user
+message: Fix these 3 TypeScript compile-time errors:
+
+1. src/bad-file.tsx:2:1 - Cannot find name 'nonExistentFunction1'. (TS2304)
+2. src/bad-file.tsx:3:1 - Cannot find name 'nonExistentFunction2'. (TS2304)
+3. src/bad-file.tsx:4:1 - Cannot find name 'nonExistentFunction3'. (TS2304)
+
+Please fix all errors in a concise way.
\ No newline at end of file

e2e-tests/snapshots/problems.spec.ts_problems---manual-edit-1.aria.yml

+- img
+- text: 1 error
+- button "Recheck":
+  - img
+- button "Fix All":
+  - img
+- img
+- img
+- text: src/bad-file.tsx 2:1
+- paragraph: Cannot find name 'nonExistentFunction'.
\ No newline at end of file

e2e-tests/snapshots/problems.spec.ts_problems---manual-edit-2.aria.yml

+- paragraph: No problems found
+- button "Recheck":
+  - img
\ No newline at end of file

e2e-tests/snapshots/problems.spec.ts_problems---manual-edit-next-js-1.aria.yml

+- img
+- text: 1 error
+- button "Recheck":
+  - img
+- button "Fix All":
+  - img
+- img
+- img
+- text: src/bad-file.tsx 2:3
+- paragraph: Cannot find name 'nonExistentFunction'.
\ No newline at end of file

e2e-tests/snapshots/problems.spec.ts_problems---manual-edit-next-js-2.aria.yml

+- paragraph: No problems found
+- button "Recheck":
+  - img
\ No newline at end of file

e2e-tests/snapshots/problems.spec.ts_problems---manual-edit-react-vite-1.aria.yml

+- img
+- text: 1 error
+- button "Recheck":
+  - img
+- button "Fix All":
+  - img
+- img
+- img
+- text: src/bad-file.tsx 2:1
+- paragraph: Cannot find name 'nonExistentFunction'.
\ No newline at end of file

e2e-tests/snapshots/problems.spec.ts_problems---manual-edit-react-vite-2.aria.yml

+- paragraph: No problems found
+- button "Recheck":
+  - img
\ No newline at end of file

e2e-tests/snapshots/problems.spec.ts_problems-auto-fix---complex-delete-rename-write-1.aria.yml

+- paragraph: tc=create-ts-errors-complex
+- paragraph: Tests delete-rename-write order
+- img
+- text: main.tsx Delete src/main.tsx
+- img
+- text: "App.tsx → main.tsx Rename From: src/App.tsx To: src/main.tsx"
+- img
+- text: main.tsx
+- img
+- text: "src/main.tsx Summary: final main.tsx file."
+- paragraph: EOM
+- img
+- text: Auto-fix1 problems
+- img
+- img
+- text: bad-file.ts
+- img
+- text: "src/bad-file.ts Summary: Fix remaining error."
+- paragraph: "[[dyad-dump-path=*]]"
+- img
+- text: Auto-fix1 problems
+- img
+- img
+- text: bad-file.ts
+- img
+- text: "src/bad-file.ts Summary: Fix remaining error."
+- paragraph: "[[dyad-dump-path=*]]"
+- button "Retry":
+  - img
\ No newline at end of file

e2e-tests/snapshots/problems.spec.ts_problems-auto-fix---disabled-1.aria.yml

+- paragraph: tc=create-ts-errors
+- paragraph: This will get a TypeScript error.
+- img
+- text: bad-file.ts
+- img
+- text: "src/bad-file.ts Summary: This will get a TypeScript error."
+- paragraph: EOM
+- button "Retry":
+  - img
\ No newline at end of file

e2e-tests/snapshots/problems.spec.ts_problems-auto-fix---enabled-1.aria.yml

+- paragraph: tc=create-ts-errors
+- paragraph: This will get a TypeScript error.
+- img
+- text: bad-file.ts
+- img
+- text: "src/bad-file.ts Summary: This will get a TypeScript error."
+- paragraph: EOM
+- img
+- text: Auto-fix2 problems
+- img
+- img
+- text: bad-file.ts
+- img
+- text: "src/bad-file.ts Summary: Fix 2 errors and introduce a new error."
+- paragraph: "[[dyad-dump-path=*]]"
+- img
+- text: Auto-fix1 problems
+- img
+- img
+- text: bad-file.ts
+- img
+- text: "src/bad-file.ts Summary: Fix remaining error."
+- paragraph: "[[dyad-dump-path=*]]"
+- button "Retry":
+  - img
\ No newline at end of file

e2e-tests/snapshots/problems.spec.ts_problems-auto-fix---gives-up-after-2-attempts-1.aria.yml

+- img
+- text: Auto-fix5 problems
+- img
+- text: "1"
+- img
+- text: /src\/bad-file\.ts 1:\d+ TS2307/
+- paragraph: Cannot find module 'non-existent-class' or its corresponding type declarations.
+- text: "2"
+- img
+- text: /src\/bad-file\.ts 2:\d+ TS2307/
+- paragraph: Cannot find module 'non-existent-class' or its corresponding type declarations.
+- text: "3"
+- img
+- text: /src\/bad-file\.ts 3:\d+ TS2307/
+- paragraph: Cannot find module 'non-existent-class' or its corresponding type declarations.
+- text: "4"
+- img
+- text: /src\/bad-file\.ts 4:\d+ TS2307/
+- paragraph: Cannot find module 'non-existent-class' or its corresponding type declarations.
+- text: "5"
+- img
+- text: /src\/bad-file\.ts 5:\d+ TS2307/
+- paragraph: Cannot find module 'non-existent-class' or its corresponding type declarations.
\ No newline at end of file

e2e-tests/snapshots/problems.spec.ts_problems-auto-fix---gives-up-after-2-attempts-2.aria.yml

+- paragraph: tc=create-unfixable-ts-errors
+- paragraph: This should not get fixed
+- img
+- text: bad-file.ts
+- img
+- text: "src/bad-file.ts Summary: This will produce 5 TypeScript errors."
+- paragraph: EOM
+- img
+- text: Auto-fix5 problems
+- img
+- img
+- text: file1.txt
+- img
+- text: file1.txt
+- paragraph: More EOM
+- paragraph: "[[dyad-dump-path=*]]"
+- img
+- text: Auto-fix5 problems
+- img
+- text: "1"
+- img
+- text: /src\/bad-file\.ts 1:\d+ TS2307/
+- paragraph: Cannot find module 'non-existent-class' or its corresponding type declarations.
+- text: "2"
+- img
+- text: /src\/bad-file\.ts 2:\d+ TS2307/
+- paragraph: Cannot find module 'non-existent-class' or its corresponding type declarations.
+- text: "3"
+- img
+- text: /src\/bad-file\.ts 3:\d+ TS2307/
+- paragraph: Cannot find module 'non-existent-class' or its corresponding type declarations.
+- text: "4"
+- img
+- text: /src\/bad-file\.ts 4:\d+ TS2307/
+- paragraph: Cannot find module 'non-existent-class' or its corresponding type declarations.
+- text: "5"
+- img
+- text: /src\/bad-file\.ts 5:\d+ TS2307/
+- paragraph: Cannot find module 'non-existent-class' or its corresponding type declarations.
+- img
+- text: file1.txt
+- img
+- text: file1.txt
+- paragraph: More EOM
+- paragraph: "[[dyad-dump-path=*]]"
+- button "Retry":
+  - img
\ No newline at end of file

e2e-tests/snapshots/telemetry.spec.ts_telemetry---accept-1.txt

@@ -11,5 +11,6 @@
   "enableProLazyEditsMode": true,
   "enableProSmartFilesContextMode": true,
   "selectedChatMode": "build",
+  "enableAutoFixProblems": true,
   "isTestMode": true
 }
\ No newline at end of file

e2e-tests/snapshots/telemetry.spec.ts_telemetry---accept-2.txt

@@ -12,5 +12,6 @@
   "enableProLazyEditsMode": true,
   "enableProSmartFilesContextMode": true,
   "selectedChatMode": "build",
+  "enableAutoFixProblems": true,
   "isTestMode": true
 }
\ No newline at end of file

e2e-tests/snapshots/telemetry.spec.ts_telemetry---later-1.txt

@@ -11,5 +11,6 @@
   "enableProLazyEditsMode": true,
   "enableProSmartFilesContextMode": true,
   "selectedChatMode": "build",
+  "enableAutoFixProblems": true,
   "isTestMode": true
 }
\ No newline at end of file

e2e-tests/snapshots/telemetry.spec.ts_telemetry---later-2.txt

@@ -12,5 +12,6 @@
   "enableProLazyEditsMode": true,
   "enableProSmartFilesContextMode": true,
   "selectedChatMode": "build",
+  "enableAutoFixProblems": true,
   "isTestMode": true
 }
\ No newline at end of file

e2e-tests/snapshots/telemetry.spec.ts_telemetry---reject-1.txt

@@ -11,5 +11,6 @@
   "enableProLazyEditsMode": true,
   "enableProSmartFilesContextMode": true,
   "selectedChatMode": "build",
+  "enableAutoFixProblems": true,
   "isTestMode": true
 }
\ No newline at end of file

e2e-tests/snapshots/telemetry.spec.ts_telemetry---reject-2.txt

@@ -12,5 +12,6 @@
   "enableProLazyEditsMode": true,
   "enableProSmartFilesContextMode": true,
   "selectedChatMode": "build",
+  "enableAutoFixProblems": true,
   "isTestMode": true
 }
\ No newline at end of file

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

@@ -21,5 +21,6 @@
   "enableProLazyEditsMode": true,
   "enableProSmartFilesContextMode": true,
   "selectedChatMode": "build",
+  "enableAutoFixProblems": true,
   "isTestMode": true
 }
\ No newline at end of file

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

@@ -21,5 +21,6 @@
   "enableProLazyEditsMode": true,
   "enableProSmartFilesContextMode": true,
   "selectedChatMode": "build",
+  "enableAutoFixProblems": true,
   "isTestMode": true
 }
\ No newline at end of file

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

@@ -21,5 +21,6 @@
   "enableProLazyEditsMode": true,
   "enableProSmartFilesContextMode": true,
   "selectedChatMode": "build",
+  "enableAutoFixProblems": true,
   "isTestMode": true
 }
\ No newline at end of file

e2e-tests/template-create-nextjs.spec.ts

@@ -3,10 +3,7 @@ import { expect } from "@playwright/test";
 
 test("create next.js app", async ({ po }) => {
   await po.setUp();
-  // Select Next.js template
-  await po.goToHubTab();
-  await po.selectTemplate("Next.js Template");
-  await po.goToAppsTab();
+  await po.selectHubTemplate("Next.js Template");
 
   // Create an app
   await po.sendPrompt("tc=edit-made-with-dyad");

src/__tests__/__snapshots__/problem_prompt.test.ts.snap

+// Vitest Snapshot v1, https://vitest.dev/guide/snapshot.html
+
+exports[`problem_prompt > createConciseProblemFixPrompt > should format a concise prompt for multiple errors 1`] = `
+"Fix these 2 TypeScript compile-time errors:
+
+1. src/main.ts:5:12 - Cannot find module 'react-dom/client' or its corresponding type declarations. (TS2307)
+2. src/components/Modal.tsx:35:20 - Property 'isOpen' does not exist on type 'IntrinsicAttributes & ModalProps'. (TS2339)
+
+Please fix all errors in a concise way."
+`;
+
+exports[`problem_prompt > createConciseProblemFixPrompt > should format a concise prompt for single error 1`] = `
+"Fix these 1 TypeScript compile-time error:
+
+1. src/App.tsx:10:5 - Cannot find name 'consol'. Did you mean 'console'? (TS2552)
+
+Please fix all errors in a concise way."
+`;
+
+exports[`problem_prompt > createConciseProblemFixPrompt > should return a short message when no problems exist 1`] = `"No TypeScript problems detected."`;
+
+exports[`problem_prompt > createProblemFixPrompt > should format a single error correctly 1`] = `
+"Fix these 1 TypeScript compile-time error:
+
+1. src/components/Button.tsx:15:23 - Property 'onClick' does not exist on type 'ButtonProps'. (TS2339)
+
+Please fix all errors in a concise way."
+`;
+
+exports[`problem_prompt > createProblemFixPrompt > should format multiple errors across multiple files 1`] = `
+"Fix these 4 TypeScript compile-time errors:
+
+1. src/components/Button.tsx:15:23 - Property 'onClick' does not exist on type 'ButtonProps'. (TS2339)
+2. src/components/Button.tsx:8:12 - Type 'string | undefined' is not assignable to type 'string'. (TS2322)
+3. src/hooks/useApi.ts:42:5 - Argument of type 'unknown' is not assignable to parameter of type 'string'. (TS2345)
+4. src/utils/helpers.ts:45:8 - Function lacks ending return statement and return type does not include 'undefined'. (TS2366)
+
+Please fix all errors in a concise way."
+`;
+
+exports[`problem_prompt > createProblemFixPrompt > should handle realistic React TypeScript errors 1`] = `
+"Fix these 4 TypeScript compile-time errors:
+
+1. src/components/UserProfile.tsx:12:35 - Type '{ children: string; }' is missing the following properties from type 'UserProfileProps': user, onEdit (TS2739)
+2. src/components/UserProfile.tsx:25:15 - Object is possibly 'null'. (TS2531)
+3. src/hooks/useLocalStorage.ts:18:12 - Type 'string | null' is not assignable to type 'T'. (TS2322)
+4. src/types/api.ts:45:3 - Duplicate identifier 'UserRole'. (TS2300)
+
+Please fix all errors in a concise way."
+`;
+
+exports[`problem_prompt > createProblemFixPrompt > should return a message when no problems exist 1`] = `"No TypeScript problems detected."`;
+
+exports[`problem_prompt > realistic TypeScript error scenarios > should handle common React + TypeScript errors 1`] = `
+"Fix these 4 TypeScript compile-time errors:
+
+1. src/components/ProductCard.tsx:22:18 - Property 'price' is missing in type '{ name: string; description: string; }' but required in type 'Product'. (TS2741)
+2. src/components/SearchInput.tsx:15:45 - Type '(value: string) => void' is not assignable to type 'ChangeEventHandler<HTMLInputElement>'. (TS2322)
+3. src/api/userService.ts:8:1 - Function lacks ending return statement and return type does not include 'undefined'. (TS2366)
+4. src/utils/dataProcessor.ts:34:25 - Object is possibly 'undefined'. (TS2532)
+
+Please fix all errors in a concise way."
+`;

src/__tests__/problem_prompt.test.ts

+import { describe, it, expect } from "vitest";
+import { createProblemFixPrompt } from "../shared/problem_prompt";
+import type { ProblemReport } from "../ipc/ipc_types";
+
+describe("problem_prompt", () => {
+  describe("createProblemFixPrompt", () => {
+    it("should return a message when no problems exist", () => {
+      const problemReport: ProblemReport = {
+        problems: [],
+      };
+
+      const result = createProblemFixPrompt(problemReport);
+      expect(result).toMatchSnapshot();
+    });
+
+    it("should format a single error correctly", () => {
+      const problemReport: ProblemReport = {
+        problems: [
+          {
+            file: "src/components/Button.tsx",
+            line: 15,
+            column: 23,
+            message: "Property 'onClick' does not exist on type 'ButtonProps'.",
+            code: 2339,
+          },
+        ],
+      };
+
+      const result = createProblemFixPrompt(problemReport);
+      expect(result).toMatchSnapshot();
+    });
+
+    it("should format multiple errors across multiple files", () => {
+      const problemReport: ProblemReport = {
+        problems: [
+          {
+            file: "src/components/Button.tsx",
+            line: 15,
+            column: 23,
+            message: "Property 'onClick' does not exist on type 'ButtonProps'.",
+            code: 2339,
+          },
+          {
+            file: "src/components/Button.tsx",
+            line: 8,
+            column: 12,
+            message:
+              "Type 'string | undefined' is not assignable to type 'string'.",
+            code: 2322,
+          },
+          {
+            file: "src/hooks/useApi.ts",
+            line: 42,
+            column: 5,
+            message:
+              "Argument of type 'unknown' is not assignable to parameter of type 'string'.",
+            code: 2345,
+          },
+          {
+            file: "src/utils/helpers.ts",
+            line: 45,
+            column: 8,
+            message:
+              "Function lacks ending return statement and return type does not include 'undefined'.",
+            code: 2366,
+          },
+        ],
+      };
+
+      const result = createProblemFixPrompt(problemReport);
+      expect(result).toMatchSnapshot();
+    });
+
+    it("should handle realistic React TypeScript errors", () => {
+      const problemReport: ProblemReport = {
+        problems: [
+          {
+            file: "src/components/UserProfile.tsx",
+            line: 12,
+            column: 35,
+            message:
+              "Type '{ children: string; }' is missing the following properties from type 'UserProfileProps': user, onEdit",
+            code: 2739,
+          },
+          {
+            file: "src/components/UserProfile.tsx",
+            line: 25,
+            column: 15,
+            message: "Object is possibly 'null'.",
+            code: 2531,
+          },
+          {
+            file: "src/hooks/useLocalStorage.ts",
+            line: 18,
+            column: 12,
+            message: "Type 'string | null' is not assignable to type 'T'.",
+            code: 2322,
+          },
+          {
+            file: "src/types/api.ts",
+            line: 45,
+            column: 3,
+            message: "Duplicate identifier 'UserRole'.",
+            code: 2300,
+          },
+        ],
+      };
+
+      const result = createProblemFixPrompt(problemReport);
+      expect(result).toMatchSnapshot();
+    });
+  });
+
+  describe("createConciseProblemFixPrompt", () => {
+    it("should return a short message when no problems exist", () => {
+      const problemReport: ProblemReport = {
+        problems: [],
+      };
+
+      const result = createProblemFixPrompt(problemReport);
+      expect(result).toMatchSnapshot();
+    });
+
+    it("should format a concise prompt for single error", () => {
+      const problemReport: ProblemReport = {
+        problems: [
+          {
+            file: "src/App.tsx",
+            line: 10,
+            column: 5,
+            message: "Cannot find name 'consol'. Did you mean 'console'?",
+            code: 2552,
+          },
+        ],
+      };
+
+      const result = createProblemFixPrompt(problemReport);
+      expect(result).toMatchSnapshot();
+    });
+
+    it("should format a concise prompt for multiple errors", () => {
+      const problemReport: ProblemReport = {
+        problems: [
+          {
+            file: "src/main.ts",
+            line: 5,
+            column: 12,
+            message:
+              "Cannot find module 'react-dom/client' or its corresponding type declarations.",
+            code: 2307,
+          },
+          {
+            file: "src/components/Modal.tsx",
+            line: 35,
+            column: 20,
+            message:
+              "Property 'isOpen' does not exist on type 'IntrinsicAttributes & ModalProps'.",
+            code: 2339,
+          },
+        ],
+      };
+
+      const result = createProblemFixPrompt(problemReport);
+      expect(result).toMatchSnapshot();
+    });
+  });
+
+  describe("realistic TypeScript error scenarios", () => {
+    it("should handle common React + TypeScript errors", () => {
+      const problemReport: ProblemReport = {
+        problems: [
+          // Missing interface property
+          {
+            file: "src/components/ProductCard.tsx",
+            line: 22,
+            column: 18,
+            message:
+              "Property 'price' is missing in type '{ name: string; description: string; }' but required in type 'Product'.",
+            code: 2741,
+          },
+          // Incorrect event handler type
+          {
+            file: "src/components/SearchInput.tsx",
+            line: 15,
+            column: 45,
+            message:
+              "Type '(value: string) => void' is not assignable to type 'ChangeEventHandler<HTMLInputElement>'.",
+            code: 2322,
+          },
+          // Async/await without Promise return type
+          {
+            file: "src/api/userService.ts",
+            line: 8,
+            column: 1,
+            message:
+              "Function lacks ending return statement and return type does not include 'undefined'.",
+            code: 2366,
+          },
+          // Strict null check
+          {
+            file: "src/utils/dataProcessor.ts",
+            line: 34,
+            column: 25,
+            message: "Object is possibly 'undefined'.",
+            code: 2532,
+          },
+        ],
+      };
+
+      const result = createProblemFixPrompt(problemReport);
+      expect(result).toMatchSnapshot();
+    });
+  });
+});

src/atoms/appAtoms.ts

@@ -7,7 +7,7 @@ export const selectedAppIdAtom = atom<number | null>(null);
 export const appsListAtom = atom<App[]>([]);
 export const appBasePathAtom = atom<string>("");
 export const versionsListAtom = atom<Version[]>([]);
-export const previewModeAtom = atom<"preview" | "code">("preview");
+export const previewModeAtom = atom<"preview" | "code" | "problems">("preview");
 export const selectedVersionIdAtom = atom<string | null>(null);
 export const appOutputAtom = atom<AppOutput[]>([]);
 export const appUrlAtom = atom<

src/components/AutoFixProblemsSwitch.tsx

+import { useSettings } from "@/hooks/useSettings";
+import { Label } from "@/components/ui/label";
+import { Switch } from "@/components/ui/switch";
+
+export function AutoFixProblemsSwitch() {
+  const { settings, updateSettings } = useSettings();
+  return (
+    <div className="flex items-center space-x-2">
+      <Switch
+        id="auto-fix-problems"
+        checked={settings?.enableAutoFixProblems}
+        onCheckedChange={() => {
+          updateSettings({
+            enableAutoFixProblems: !settings?.enableAutoFixProblems,
+          });
+        }}
+      />
+      <Label htmlFor="auto-fix-problems">Auto-fix problems</Label>
+    </div>
+  );
+}

src/components/chat/ChatInput.tsx

@@ -63,6 +63,7 @@ import { ChatInputControls } from "../ChatInputControls";
 import { ChatErrorBox } from "./ChatErrorBox";
 import { selectedComponentPreviewAtom } from "@/atoms/previewAtoms";
 import { SelectedComponentDisplay } from "./SelectedComponentDisplay";
+import { useCheckProblems } from "@/hooks/useCheckProblems";
 
 const showTokenBarAtom = atom(false);
 
@@ -84,7 +85,7 @@ export function ChatInput({ chatId }: { chatId?: number }) {
   const [selectedComponent, setSelectedComponent] = useAtom(
     selectedComponentPreviewAtom,
   );
-
+  const { checkProblems } = useCheckProblems(appId);
   // Use the attachments hook
   const {
     attachments,
@@ -207,6 +208,7 @@ export function ChatInput({ chatId }: { chatId?: number }) {
       setIsApproving(false);
       setIsPreviewOpen(true);
       refreshVersions();
+      checkProblems();
 
       // Keep same as handleReject
       refreshProposal();

src/components/chat/DyadMarkdownParser.tsx

@@ -15,6 +15,7 @@ import { useAtomValue } from "jotai";
 import { isStreamingAtom } from "@/atoms/chatAtoms";
 import { CustomTagState } from "./stateTypes";
 import { DyadOutput } from "./DyadOutput";
+import { DyadProblemSummary } from "./DyadProblemSummary";
 import { IpcClient } from "@/ipc/ipc_client";
 
 interface DyadMarkdownParserProps {
@@ -117,6 +118,7 @@ function preprocessUnclosedTags(content: string): {
     "dyad-execute-sql",
     "dyad-add-integration",
     "dyad-output",
+    "dyad-problem-report",
     "dyad-chat-summary",
     "dyad-edit",
     "dyad-codebase-context",
@@ -182,6 +184,7 @@ function parseCustomTags(content: string): ContentPiece[] {
     "dyad-execute-sql",
     "dyad-add-integration",
     "dyad-output",
+    "dyad-problem-report",
     "dyad-chat-summary",
     "dyad-edit",
     "dyad-codebase-context",
@@ -404,6 +407,13 @@ function renderCustomTag(
         </DyadOutput>
       );
 
+    case "dyad-problem-report":
+      return (
+        <DyadProblemSummary summary={attributes.summary}>
+          {content}
+        </DyadProblemSummary>
+      );
+
     case "dyad-chat-summary":
       // Don't render anything for dyad-chat-summary
       return null;

src/components/chat/DyadProblemSummary.tsx

+import React, { useState } from "react";
+import {
+  ChevronsDownUp,
+  ChevronsUpDown,
+  AlertTriangle,
+  FileText,
+} from "lucide-react";
+import type { Problem } from "@/ipc/ipc_types";
+
+interface DyadProblemSummaryProps {
+  summary?: string;
+  children?: React.ReactNode;
+}
+
+interface ProblemItemProps {
+  problem: Problem;
+  index: number;
+}
+
+const ProblemItem: React.FC<ProblemItemProps> = ({ problem, index }) => {
+  return (
+    <div className="flex items-start gap-3 py-2 px-3 border-b border-gray-200 dark:border-gray-700 last:border-b-0">
+      <div className="flex-shrink-0 w-6 h-6 rounded-full bg-gray-100 dark:bg-gray-800 flex items-center justify-center mt-0.5">
+        <span className="text-xs font-medium text-gray-600 dark:text-gray-400">
+          {index + 1}
+        </span>
+      </div>
+      <div className="flex-1 min-w-0">
+        <div className="flex items-center gap-2 mb-2">
+          <FileText size={14} className="text-gray-500 flex-shrink-0" />
+          <span className="text-sm font-medium text-gray-900 dark:text-gray-100 truncate">
+            {problem.file}
+          </span>
+
+          <span className="text-xs text-gray-500 dark:text-gray-400">
+            {problem.line}:{problem.column}
+          </span>
+          <span className="text-xs bg-gray-100 dark:bg-gray-800 px-2 py-0.5 rounded text-gray-600 dark:text-gray-300">
+            TS{problem.code}
+          </span>
+        </div>
+        <p className="text-sm text-gray-700 dark:text-gray-300 leading-relaxed">
+          {problem.message}
+        </p>
+      </div>
+    </div>
+  );
+};
+
+export const DyadProblemSummary: React.FC<DyadProblemSummaryProps> = ({
+  summary,
+  children,
+}) => {
+  const [isContentVisible, setIsContentVisible] = useState(false);
+
+  // Parse problems from children content if available
+  const problems: Problem[] = React.useMemo(() => {
+    if (!children || typeof children !== "string") return [];
+
+    // Parse structured format with <problem> tags
+    const problemTagRegex =
+      /<problem\s+file="([^"]+)"\s+line="(\d+)"\s+column="(\d+)"\s+code="(\d+)">([^<]+)<\/problem>/g;
+    const problems: Problem[] = [];
+    let match;
+
+    while ((match = problemTagRegex.exec(children)) !== null) {
+      try {
+        problems.push({
+          file: match[1],
+          line: parseInt(match[2], 10),
+          column: parseInt(match[3], 10),
+          message: match[5].trim(),
+          code: parseInt(match[4], 10),
+        });
+      } catch {
+        return [
+          {
+            file: "unknown",
+            line: 0,
+            column: 0,
+            message: children,
+            code: 0,
+          },
+        ];
+      }
+    }
+
+    return problems;
+  }, [children]);
+
+  const totalProblems = problems.length;
+  const displaySummary =
+    summary || `${totalProblems} problems found (TypeScript errors)`;
+
+  return (
+    <div
+      className="bg-(--background-lightest) hover:bg-(--background-lighter) rounded-lg px-4 py-2 border border-border my-2 cursor-pointer"
+      onClick={() => setIsContentVisible(!isContentVisible)}
+      data-testid="problem-summary"
+    >
+      <div className="flex items-center justify-between">
+        <div className="flex items-center gap-2">
+          <AlertTriangle
+            size={16}
+            className="text-amber-600 dark:text-amber-500"
+          />
+          <span className="text-gray-700 dark:text-gray-300 font-medium text-sm">
+            <span className="font-bold mr-2 outline-2 outline-amber-200 dark:outline-amber-700 bg-amber-100 dark:bg-amber-900/30 text-amber-800 dark:text-amber-200 rounded-md px-1">
+              Auto-fix
+            </span>
+            {displaySummary}
+          </span>
+        </div>
+        <div className="flex items-center">
+          {isContentVisible ? (
+            <ChevronsDownUp
+              size={20}
+              className="text-gray-500 hover:text-gray-700 dark:text-gray-400 dark:hover:text-gray-200"
+            />
+          ) : (
+            <ChevronsUpDown
+              size={20}
+              className="text-gray-500 hover:text-gray-700 dark:text-gray-400 dark:hover:text-gray-200"
+            />
+          )}
+        </div>
+      </div>
+
+      {/* Content area - show individual problems */}
+      {isContentVisible && totalProblems > 0 && (
+        <div className="mt-4">
+          <div className="bg-white dark:bg-gray-800 rounded-lg border border-gray-200 dark:border-gray-700 overflow-hidden">
+            {problems.map((problem, index) => (
+              <ProblemItem
+                key={`${problem.file}-${problem.line}-${problem.column}-${index}`}
+                problem={problem}
+                index={index}
+              />
+            ))}
+          </div>
+        </div>
+      )}
+
+      {/* Fallback content area for raw children */}
+      {isContentVisible && totalProblems === 0 && children && (
+        <div className="mt-4 text-sm text-gray-800 dark:text-gray-200">
+          <pre className="whitespace-pre-wrap font-mono text-xs bg-gray-100 dark:bg-gray-800 p-3 rounded">
+            {children}
+          </pre>
+        </div>
+      )}
+    </div>
+  );
+};

src/components/preview_panel/PreviewPanel.tsx

@@ -9,6 +9,7 @@ import { IpcClient } from "@/ipc/ipc_client";
 
 import { CodeView } from "./CodeView";
 import { PreviewIframe } from "./PreviewIframe";
+import { Problems } from "./Problems";
 import {
   Eye,
   Code,
@@ -19,6 +20,7 @@ import {
   Cog,
   Power,
   Trash2,
+  AlertTriangle,
 } from "lucide-react";
 import { motion } from "framer-motion";
 import { useEffect, useRef, useState, useCallback } from "react";
@@ -33,8 +35,9 @@ import {
 } from "@/components/ui/dropdown-menu";
 import { showError, showSuccess } from "@/lib/toast";
 import { useMutation } from "@tanstack/react-query";
+import { useCheckProblems } from "@/hooks/useCheckProblems";
 
-type PreviewMode = "preview" | "code";
+type PreviewMode = "preview" | "code" | "problems";
 
 interface PreviewHeaderProps {
   previewMode: PreviewMode;
@@ -57,35 +60,109 @@ const PreviewHeader = ({
   onRestart,
   onCleanRestart,
   onClearSessionData,
-}: PreviewHeaderProps) => (
+}: PreviewHeaderProps) => {
+  const selectedAppId = useAtomValue(selectedAppIdAtom);
+  const previewRef = useRef<HTMLButtonElement>(null);
+  const codeRef = useRef<HTMLButtonElement>(null);
+  const problemsRef = useRef<HTMLButtonElement>(null);
+  const [indicatorStyle, setIndicatorStyle] = useState({ left: 0, width: 0 });
+  const { problemReport } = useCheckProblems(selectedAppId);
+  // Get the problem count for the selected app
+  const problemCount = problemReport ? problemReport.problems.length : 0;
+
+  // Format the problem count for display
+  const formatProblemCount = (count: number): string => {
+    if (count === 0) return "";
+    if (count > 100) return "100+";
+    return count.toString();
+  };
+
+  const displayCount = formatProblemCount(problemCount);
+
+  // Update indicator position when mode changes
+  useEffect(() => {
+    const updateIndicator = () => {
+      let targetRef: React.RefObject<HTMLButtonElement | null>;
+
+      switch (previewMode) {
+        case "preview":
+          targetRef = previewRef;
+          break;
+        case "code":
+          targetRef = codeRef;
+          break;
+        case "problems":
+          targetRef = problemsRef;
+          break;
+        default:
+          return;
+      }
+
+      if (targetRef.current) {
+        const button = targetRef.current;
+        const container = button.parentElement;
+        if (container) {
+          const containerRect = container.getBoundingClientRect();
+          const buttonRect = button.getBoundingClientRect();
+          const left = buttonRect.left - containerRect.left;
+          const width = buttonRect.width;
+
+          setIndicatorStyle({ left, width });
+        }
+      }
+    };
+
+    // Small delay to ensure DOM is updated
+    const timeoutId = setTimeout(updateIndicator, 10);
+    return () => clearTimeout(timeoutId);
+  }, [previewMode, displayCount]);
+
+  return (
     <div className="flex items-center justify-between px-4 py-2 border-b border-border">
-    <div className="relative flex space-x-2 bg-[var(--background-darkest)] rounded-md p-0.5">
+      <div className="relative flex bg-[var(--background-darkest)] rounded-md p-0.5">
+        <motion.div
+          className="absolute top-0.5 bottom-0.5 bg-[var(--background-lightest)] shadow rounded-md"
+          animate={{
+            left: indicatorStyle.left,
+            width: indicatorStyle.width,
+          }}
+          transition={{
+            type: "spring",
+            stiffness: 600,
+            damping: 35,
+            mass: 0.6,
+          }}
+        />
         <button
-        className="relative flex items-center space-x-1 px-3 py-1 rounded-md text-sm z-10"
+          data-testid="preview-mode-button"
+          ref={previewRef}
+          className="relative flex items-center gap-1 px-2 py-1 rounded-md text-sm font-medium z-10"
           onClick={() => setPreviewMode("preview")}
         >
-        {previewMode === "preview" && (
-          <motion.div
-            layoutId="activeIndicator"
-            className="absolute inset-0 bg-(--background-lightest) shadow rounded-md -z-1"
-            transition={{ type: "spring", stiffness: 500, damping: 35 }}
-          />
-        )}
-        <Eye size={16} />
+          <Eye size={14} />
           <span>Preview</span>
         </button>
         <button
-        className="relative flex items-center space-x-1 px-3 py-1 rounded-md text-sm z-10"
-        onClick={() => setPreviewMode("code")}
+          data-testid="problems-mode-button"
+          ref={problemsRef}
+          className="relative flex items-center gap-1 px-2 py-1 rounded-md text-sm font-medium z-10"
+          onClick={() => setPreviewMode("problems")}
         >
-        {previewMode === "code" && (
-          <motion.div
-            layoutId="activeIndicator"
-            className="absolute inset-0 bg-(--background-lightest) shadow rounded-md -z-1"
-            transition={{ type: "spring", stiffness: 500, damping: 35 }}
-          />
+          <AlertTriangle size={14} />
+          <span>Problems</span>
+          {displayCount && (
+            <span className="ml-0.5 px-1 py-0.5 text-xs font-medium bg-red-100 dark:bg-red-900/30 text-red-700 dark:text-red-300 rounded-full min-w-[16px] text-center">
+              {displayCount}
+            </span>
           )}
-        <Code size={16} />
+        </button>
+        <button
+          data-testid="code-mode-button"
+          ref={codeRef}
+          className="relative flex items-center gap-1 px-2 py-1 rounded-md text-sm font-medium z-10"
+          onClick={() => setPreviewMode("code")}
+        >
+          <Code size={14} />
           <span>Code</span>
         </button>
       </div>
@@ -131,7 +208,8 @@ const PreviewHeader = ({
         </DropdownMenu>
       </div>
     </div>
-);
+  );
+};
 
 // Console header component
 const ConsoleHeader = ({
@@ -262,8 +340,10 @@ export function PreviewPanel() {
             <div className="h-full overflow-y-auto">
               {previewMode === "preview" ? (
                 <PreviewIframe key={key} loading={loading} />
-              ) : (
+              ) : previewMode === "code" ? (
                 <CodeView loading={loading} app={app} />
+              ) : (
+                <Problems />
               )}
             </div>
           </Panel>

src/components/preview_panel/Problems.tsx

+import { useAtom, useAtomValue } from "jotai";
+import { selectedChatIdAtom } from "@/atoms/chatAtoms";
+import { selectedAppIdAtom } from "@/atoms/appAtoms";
+import {
+  AlertTriangle,
+  XCircle,
+  FileText,
+  Wrench,
+  RefreshCw,
+} from "lucide-react";
+import { Problem, ProblemReport } from "@/ipc/ipc_types";
+import { Button } from "@/components/ui/button";
+
+import { useStreamChat } from "@/hooks/useStreamChat";
+import { useCheckProblems } from "@/hooks/useCheckProblems";
+import { createProblemFixPrompt } from "@/shared/problem_prompt";
+import { showError } from "@/lib/toast";
+
+interface ProblemItemProps {
+  problem: Problem;
+}
+
+const ProblemItem = ({ problem }: ProblemItemProps) => {
+  return (
+    <div className="flex items-start gap-3 p-3 border-b border-border hover:bg-[var(--background-darkest)] transition-colors">
+      <div className="flex-shrink-0 mt-0.5">
+        <XCircle size={16} className="text-red-500" />
+      </div>
+      <div className="flex-1 min-w-0">
+        <div className="flex items-center gap-2 mb-1">
+          <FileText size={14} className="text-muted-foreground flex-shrink-0" />
+          <span className="text-sm font-medium truncate">{problem.file}</span>
+
+          <span className="text-xs text-muted-foreground">
+            {problem.line}:{problem.column}
+          </span>
+        </div>
+        <p className="text-sm text-foreground leading-relaxed">
+          {problem.message}
+        </p>
+      </div>
+    </div>
+  );
+};
+
+interface RecheckButtonProps {
+  appId: number;
+  size?: "sm" | "default" | "lg";
+  variant?:
+    | "default"
+    | "destructive"
+    | "outline"
+    | "secondary"
+    | "ghost"
+    | "link";
+  className?: string;
+}
+
+const RecheckButton = ({
+  appId,
+  size = "sm",
+  variant = "outline",
+  className = "h-7 px-3 text-xs",
+}: RecheckButtonProps) => {
+  const { checkProblems, isChecking } = useCheckProblems(appId);
+
+  const handleRecheck = async () => {
+    const res = await checkProblems();
+    if (res.error) {
+      showError(res.error);
+    }
+  };
+
+  return (
+    <Button
+      size={size}
+      variant={variant}
+      onClick={handleRecheck}
+      disabled={isChecking}
+      className={className}
+      data-testid="recheck-button"
+    >
+      <RefreshCw
+        size={14}
+        className={`mr-1 ${isChecking ? "animate-spin" : ""}`}
+      />
+      {isChecking ? "Checking..." : "Recheck"}
+    </Button>
+  );
+};
+
+interface ProblemsSummaryProps {
+  problemReport: ProblemReport;
+  appId: number;
+}
+
+const ProblemsSummary = ({ problemReport, appId }: ProblemsSummaryProps) => {
+  const { streamMessage } = useStreamChat();
+  const { problems } = problemReport;
+  const totalErrors = problems.length;
+  const [selectedChatId] = useAtom(selectedChatIdAtom);
+  const handleFixAll = () => {
+    if (!selectedChatId) {
+      return;
+    }
+    streamMessage({
+      prompt: createProblemFixPrompt(problemReport),
+      chatId: selectedChatId,
+    });
+  };
+
+  if (problems.length === 0) {
+    return (
+      <div className="flex flex-col items-center justify-center h-32 text-center">
+        <div className="w-12 h-12 rounded-full bg-green-100 dark:bg-green-900/20 flex items-center justify-center mb-3">
+          <div className="w-6 h-6 rounded-full bg-green-500"></div>
+        </div>
+        <p className="text-sm text-muted-foreground mb-3">No problems found</p>
+        <RecheckButton appId={appId} />
+      </div>
+    );
+  }
+
+  return (
+    <div className="flex items-center justify-between px-4 py-3 bg-[var(--background-darkest)] border-b border-border">
+      <div className="flex items-center gap-4">
+        {totalErrors > 0 && (
+          <div className="flex items-center gap-2">
+            <XCircle size={16} className="text-red-500" />
+            <span className="text-sm font-medium">
+              {totalErrors} {totalErrors === 1 ? "error" : "errors"}
+            </span>
+          </div>
+        )}
+      </div>
+      <div className="flex items-center gap-2">
+        <RecheckButton appId={appId} />
+        <Button
+          size="sm"
+          variant="default"
+          onClick={handleFixAll}
+          className="h-7 px-3 text-xs"
+          data-testid="fix-all-button"
+        >
+          <Wrench size={14} className="mr-1" />
+          Fix All
+        </Button>
+      </div>
+    </div>
+  );
+};
+
+export function Problems() {
+  return (
+    <div data-testid="problems-pane">
+      <_Problems />
+    </div>
+  );
+}
+
+export function _Problems() {
+  const selectedAppId = useAtomValue(selectedAppIdAtom);
+  const { problemReport } = useCheckProblems(selectedAppId);
+
+  if (!selectedAppId) {
+    return (
+      <div className="flex flex-col items-center justify-center h-full text-center p-8">
+        <div className="w-16 h-16 rounded-full bg-[var(--background-darkest)] flex items-center justify-center mb-4">
+          <AlertTriangle size={24} className="text-muted-foreground" />
+        </div>
+        <h3 className="text-lg font-medium mb-2">No App Selected</h3>
+        <p className="text-sm text-muted-foreground max-w-md">
+          Select an app to view TypeScript problems and diagnostic information.
+        </p>
+      </div>
+    );
+  }
+
+  if (!problemReport) {
+    return (
+      <div className="flex flex-col items-center justify-center h-full text-center p-8">
+        <div className="w-16 h-16 rounded-full bg-[var(--background-darkest)] flex items-center justify-center mb-4">
+          <FileText size={24} className="text-muted-foreground" />
+        </div>
+        <h3 className="text-lg font-medium mb-2">No Problems Data</h3>
+        <p className="text-sm text-muted-foreground max-w-md mb-4">
+          No TypeScript diagnostics available for this app yet. Problems will
+          appear here after running type checking.
+        </p>
+        <RecheckButton appId={selectedAppId} />
+      </div>
+    );
+  }
+
+  return (
+    <div className="flex flex-col h-full">
+      <ProblemsSummary problemReport={problemReport} appId={selectedAppId} />
+      <div className="flex-1 overflow-y-auto">
+        {problemReport.problems.map((problem, index) => (
+          <ProblemItem
+            key={`${problem.file}-${problem.line}-${problem.column}-${index}`}
+            problem={problem}
+          />
+        ))}
+      </div>
+    </div>
+  );
+}

src/hooks/useCheckProblems.ts

+import { useQuery } from "@tanstack/react-query";
+import { IpcClient } from "@/ipc/ipc_client";
+import type { ProblemReport } from "@/ipc/ipc_types";
+
+export function useCheckProblems(appId: number | null) {
+  const {
+    data: problemReport,
+    isLoading: isChecking,
+    error,
+    refetch: checkProblems,
+  } = useQuery<ProblemReport, Error>({
+    queryKey: ["problems", appId],
+    queryFn: async (): Promise<ProblemReport> => {
+      if (!appId) {
+        throw new Error("App ID is required");
+      }
+      const ipcClient = IpcClient.getInstance();
+      return ipcClient.checkProblems({ appId });
+    },
+    enabled: !!appId,
+    // DO NOT SHOW ERROR TOAST.
+  });
+
+  return {
+    problemReport,
+    isChecking,
+    error,
+    checkProblems,
+  };
+}

src/hooks/useStreamChat.ts

@@ -21,6 +21,7 @@ import { useRunApp } from "./useRunApp";
 import { useCountTokens } from "./useCountTokens";
 import { useUserBudgetInfo } from "./useUserBudgetInfo";
 import { usePostHog } from "posthog-js/react";
+import { useCheckProblems } from "./useCheckProblems";
 
 export function getRandomNumberId() {
   return Math.floor(Math.random() * 1_000_000_000_000_000);
@@ -41,6 +42,7 @@ export function useStreamChat({
   const { refreshAppIframe } = useRunApp();
   const { countTokens } = useCountTokens();
   const { refetchUserBudget } = useUserBudgetInfo();
+  const { checkProblems } = useCheckProblems(selectedAppId);
   const posthog = usePostHog();
   let chatId: number | undefined;
 
@@ -73,6 +75,7 @@ export function useStreamChat({
 
       setError(null);
       setIsStreaming(true);
+
       let hasIncrementedStreamCount = false;
       try {
         IpcClient.getInstance().streamMessage(prompt, {
@@ -92,6 +95,7 @@ export function useStreamChat({
             if (response.updatedFiles) {
               setIsPreviewOpen(true);
               refreshAppIframe();
+              checkProblems();
             }
             if (response.extraFiles) {
               showExtraFilesToast({
@@ -129,7 +133,14 @@ export function useStreamChat({
         setError(error instanceof Error ? error.message : String(error));
       }
     },
-    [setMessages, setIsStreaming, setIsPreviewOpen, refetchUserBudget],
+    [
+      setMessages,
+      setIsStreaming,
+      setIsPreviewOpen,
+      checkProblems,
+      selectedAppId,
+      refetchUserBudget,
+    ],
   );
 
   return {

src/ipc/handlers/problems_handlers.ts

+import { db } from "../../db";
+import { ipcMain } from "electron";
+import { apps } from "../../db/schema";
+import { eq } from "drizzle-orm";
+import { generateProblemReport } from "../processors/tsc";
+import { getDyadAppPath } from "@/paths/paths";
+import { logger } from "./app_upgrade_handlers";
+
+export function registerProblemsHandlers() {
+  // Handler to check problems using autofix with empty response
+  ipcMain.handle("check-problems", async (event, params: { appId: number }) => {
+    try {
+      // Get the app to find its path
+      const app = await db.query.apps.findFirst({
+        where: eq(apps.id, params.appId),
+      });
+
+      if (!app) {
+        throw new Error(`App not found: ${params.appId}`);
+      }
+
+      const appPath = getDyadAppPath(app.path);
+
+      // Call autofix with empty full response to just run TypeScript checking
+      const problemReport = await generateProblemReport({
+        fullResponse: "",
+        appPath,
+      });
+
+      return problemReport;
+    } catch (error) {
+      logger.error("Error checking problems:", error);
+      throw error;
+    }
+  });
+}

src/ipc/handlers/testing_chat_handlers.ts

@@ -4,6 +4,16 @@ import { cleanFullResponse } from "../utils/cleanFullResponse";
 // e.g. [dyad-qa=add-dep]
 // Canned responses for test prompts
 const TEST_RESPONSES: Record<string, string> = {
+  "ts-error": `This will get a TypeScript error.
+  
+  <dyad-write path="src/bad-file.ts" description="This will get a TypeScript error.">
+  import NonExistentClass from 'non-existent-class';
+
+  const x = new Object();
+  x.nonExistentMethod();
+  </dyad-write>
+  
+  EOM`,
   "add-dep": `I'll add that dependency for you.
   
   <dyad-add-dependency packages="deno"></dyad-add-dependency>

src/ipc/ipc_client.ts

@@ -9,6 +9,7 @@ import type {
   AppOutput,
   Chat,
   ChatResponseEnd,
+  ChatProblemsEvent,
   CreateAppParams,
   CreateAppResult,
   ListAppsResponse,
@@ -35,6 +36,7 @@ import type {
   App,
   ComponentSelection,
   AppUpgrade,
+  ProblemReport,
 } from "./ipc_types";
 import type { AppChatContext, ProposalResult } from "@/lib/schemas";
 import { showError } from "@/lib/toast";
@@ -233,6 +235,7 @@ export class IpcClient {
       onUpdate: (messages: Message[]) => void;
       onEnd: (response: ChatResponseEnd) => void;
       onError: (error: string) => void;
+      onProblems?: (problems: ChatProblemsEvent) => void;
     },
   ): void {
     const {
@@ -934,4 +937,10 @@ export class IpcClient {
   public async openAndroid(params: { appId: number }): Promise<void> {
     return this.ipcRenderer.invoke("open-android", params);
   }
+
+  public async checkProblems(params: {
+    appId: number;
+  }): Promise<ProblemReport> {
+    return this.ipcRenderer.invoke("check-problems", params);
+  }
 }

src/ipc/ipc_host.ts

@@ -22,6 +22,7 @@ import { registerProHandlers } from "./handlers/pro_handlers";
 import { registerContextPathsHandlers } from "./handlers/context_paths_handlers";
 import { registerAppUpgradeHandlers } from "./handlers/app_upgrade_handlers";
 import { registerCapacitorHandlers } from "./handlers/capacitor_handlers";
+import { registerProblemsHandlers } from "./handlers/problems_handlers";
 
 export function registerIpcHandlers() {
   // Register all IPC handlers by category
@@ -33,6 +34,7 @@ export function registerIpcHandlers() {
   registerDependencyHandlers();
   registerGithubHandlers();
   registerNodeHandlers();
+  registerProblemsHandlers();
   registerProposalHandlers();
   registerDebugHandlers();
   registerSupabaseHandlers();

src/ipc/ipc_types.ts

@@ -31,6 +31,12 @@ export interface ChatResponseEnd {
   extraFilesError?: string;
 }
 
+export interface ChatProblemsEvent {
+  chatId: number;
+  appId: number;
+  problems: ProblemReport;
+}
+
 export interface CreateAppParams {
   name: string;
 }
@@ -240,3 +246,15 @@ export interface AppUpgrade {
   manualUpgradeUrl: string;
   isNeeded: boolean;
 }
+
+export interface Problem {
+  file: string;
+  line: number;
+  column: number;
+  message: string;
+  code: number;
+}
+
+export interface ProblemReport {
+  problems: Problem[];
+}