diff --git a/claudetool/browse/browse.go b/claudetool/browse/browse.go
index e96a7f9..99f6ea7 100644
--- a/claudetool/browse/browse.go
+++ b/claudetool/browse/browse.go
@@ -182,19 +182,19 @@
 	}
 }
 
-func (b *BrowseTools) navigateRun(ctx context.Context, m json.RawMessage) ([]llm.Content, error) {
+func (b *BrowseTools) navigateRun(ctx context.Context, m json.RawMessage) llm.ToolOut {
 	var input navigateInput
 	if err := json.Unmarshal(m, &input); err != nil {
-		return nil, fmt.Errorf("invalid input: %w", err)
+		return llm.ErrorfToolOut("invalid input: %w", err)
 	}
 
 	if isPort80(input.URL) {
-		return nil, fmt.Errorf("port 80 is not the port you're looking for--port 80 is the main sketch server")
+		return llm.ErrorToolOut(fmt.Errorf("port 80 is not the port you're looking for--port 80 is the main sketch server"))
 	}
 
 	browserCtx, err := b.GetBrowserContext()
 	if err != nil {
-		return nil, err
+		return llm.ErrorToolOut(err)
 	}
 
 	// Create a timeout context for this operation
@@ -206,10 +206,10 @@
 		chromedp.WaitReady("body"),
 	)
 	if err != nil {
-		return nil, err
+		return llm.ErrorToolOut(err)
 	}
 
-	return llm.TextContent("done"), nil
+	return llm.ToolOut{LLMContent: llm.TextContent("done")}
 }
 
 // ClickTool definition
@@ -246,15 +246,15 @@
 	}
 }
 
-func (b *BrowseTools) clickRun(ctx context.Context, m json.RawMessage) ([]llm.Content, error) {
+func (b *BrowseTools) clickRun(ctx context.Context, m json.RawMessage) llm.ToolOut {
 	var input clickInput
 	if err := json.Unmarshal(m, &input); err != nil {
-		return nil, fmt.Errorf("invalid input: %w", err)
+		return llm.ErrorfToolOut("invalid input: %w", err)
 	}
 
 	browserCtx, err := b.GetBrowserContext()
 	if err != nil {
-		return nil, err
+		return llm.ErrorToolOut(err)
 	}
 
 	// Create a timeout context for this operation
@@ -273,10 +273,10 @@
 
 	err = chromedp.Run(timeoutCtx, actions...)
 	if err != nil {
-		return nil, err
+		return llm.ErrorToolOut(err)
 	}
 
-	return llm.TextContent("done"), nil
+	return llm.ToolOut{LLMContent: llm.TextContent("done")}
 }
 
 // TypeTool definition
@@ -318,15 +318,15 @@
 	}
 }
 
-func (b *BrowseTools) typeRun(ctx context.Context, m json.RawMessage) ([]llm.Content, error) {
+func (b *BrowseTools) typeRun(ctx context.Context, m json.RawMessage) llm.ToolOut {
 	var input typeInput
 	if err := json.Unmarshal(m, &input); err != nil {
-		return nil, fmt.Errorf("invalid input: %w", err)
+		return llm.ErrorfToolOut("invalid input: %w", err)
 	}
 
 	browserCtx, err := b.GetBrowserContext()
 	if err != nil {
-		return nil, err
+		return llm.ErrorToolOut(err)
 	}
 
 	// Create a timeout context for this operation
@@ -346,10 +346,10 @@
 
 	err = chromedp.Run(timeoutCtx, actions...)
 	if err != nil {
-		return nil, err
+		return llm.ErrorToolOut(err)
 	}
 
-	return llm.TextContent("done"), nil
+	return llm.ToolOut{LLMContent: llm.TextContent("done")}
 }
 
 // WaitForTool definition
@@ -381,15 +381,15 @@
 	}
 }
 
-func (b *BrowseTools) waitForRun(ctx context.Context, m json.RawMessage) ([]llm.Content, error) {
+func (b *BrowseTools) waitForRun(ctx context.Context, m json.RawMessage) llm.ToolOut {
 	var input waitForInput
 	if err := json.Unmarshal(m, &input); err != nil {
-		return nil, fmt.Errorf("invalid input: %w", err)
+		return llm.ErrorfToolOut("invalid input: %w", err)
 	}
 
 	browserCtx, err := b.GetBrowserContext()
 	if err != nil {
-		return nil, err
+		return llm.ErrorToolOut(err)
 	}
 
 	timeoutCtx, cancel := context.WithTimeout(browserCtx, parseTimeout(input.Timeout))
@@ -397,10 +397,10 @@
 
 	err = chromedp.Run(timeoutCtx, chromedp.WaitReady(input.Selector))
 	if err != nil {
-		return nil, err
+		return llm.ErrorToolOut(err)
 	}
 
-	return llm.TextContent("done"), nil
+	return llm.ToolOut{LLMContent: llm.TextContent("done")}
 }
 
 // GetTextTool definition
@@ -432,15 +432,15 @@
 	}
 }
 
-func (b *BrowseTools) getTextRun(ctx context.Context, m json.RawMessage) ([]llm.Content, error) {
+func (b *BrowseTools) getTextRun(ctx context.Context, m json.RawMessage) llm.ToolOut {
 	var input getTextInput
 	if err := json.Unmarshal(m, &input); err != nil {
-		return nil, fmt.Errorf("invalid input: %w", err)
+		return llm.ErrorfToolOut("invalid input: %w", err)
 	}
 
 	browserCtx, err := b.GetBrowserContext()
 	if err != nil {
-		return nil, err
+		return llm.ErrorToolOut(err)
 	}
 
 	// Create a timeout context for this operation
@@ -453,10 +453,10 @@
 		chromedp.Text(input.Selector, &text),
 	)
 	if err != nil {
-		return nil, err
+		return llm.ErrorToolOut(err)
 	}
 
-	return llm.TextContent("<innerText>" + text + "</innerText>"), nil
+	return llm.ToolOut{LLMContent: llm.TextContent("<innerText>" + text + "</innerText>")}
 }
 
 // EvalTool definition
@@ -488,15 +488,15 @@
 	}
 }
 
-func (b *BrowseTools) evalRun(ctx context.Context, m json.RawMessage) ([]llm.Content, error) {
+func (b *BrowseTools) evalRun(ctx context.Context, m json.RawMessage) llm.ToolOut {
 	var input evalInput
 	if err := json.Unmarshal(m, &input); err != nil {
-		return nil, fmt.Errorf("invalid input: %w", err)
+		return llm.ErrorfToolOut("invalid input: %w", err)
 	}
 
 	browserCtx, err := b.GetBrowserContext()
 	if err != nil {
-		return nil, err
+		return llm.ErrorToolOut(err)
 	}
 
 	// Create a timeout context for this operation
@@ -506,16 +506,16 @@
 	var result any
 	err = chromedp.Run(timeoutCtx, chromedp.Evaluate(input.Expression, &result))
 	if err != nil {
-		return nil, err
+		return llm.ErrorToolOut(err)
 	}
 
 	// Return the result as JSON
 	response, err := json.Marshal(result)
 	if err != nil {
-		return nil, fmt.Errorf("failed to marshal response: %w", err)
+		return llm.ErrorfToolOut("failed to marshal response: %w", err)
 	}
 
-	return llm.TextContent("<javascript_result>" + string(response) + "</javascript_result>"), nil
+	return llm.ToolOut{LLMContent: llm.TextContent("<javascript_result>" + string(response) + "</javascript_result>")}
 }
 
 // ScreenshotTool definition
@@ -552,15 +552,15 @@
 	}
 }
 
-func (b *BrowseTools) screenshotRun(ctx context.Context, m json.RawMessage) ([]llm.Content, error) {
+func (b *BrowseTools) screenshotRun(ctx context.Context, m json.RawMessage) llm.ToolOut {
 	var input screenshotInput
 	if err := json.Unmarshal(m, &input); err != nil {
-		return nil, fmt.Errorf("invalid input: %w", err)
+		return llm.ErrorfToolOut("invalid input: %w", err)
 	}
 
 	browserCtx, err := b.GetBrowserContext()
 	if err != nil {
-		return nil, err
+		return llm.ErrorToolOut(err)
 	}
 
 	// Create a timeout context for this operation
@@ -583,13 +583,13 @@
 
 	err = chromedp.Run(timeoutCtx, actions...)
 	if err != nil {
-		return nil, err
+		return llm.ErrorToolOut(err)
 	}
 
 	// Save the screenshot and get its ID for potential future reference
 	id := b.SaveScreenshot(buf)
 	if id == "" {
-		return nil, fmt.Errorf("failed to save screenshot")
+		return llm.ErrorToolOut(fmt.Errorf("failed to save screenshot"))
 	}
 
 	// Get the full path to the screenshot
@@ -599,7 +599,7 @@
 	base64Data := base64.StdEncoding.EncodeToString(buf)
 
 	// Return the screenshot directly to the LLM
-	return []llm.Content{
+	return llm.ToolOut{LLMContent: []llm.Content{
 		{
 			Type: llm.ContentTypeText,
 			Text: fmt.Sprintf("Screenshot taken (saved as %s)", screenshotPath),
@@ -609,7 +609,7 @@
 			MediaType: "image/png",
 			Data:      base64Data,
 		},
-	}, nil
+	}}
 }
 
 // ScrollIntoViewTool definition
@@ -641,15 +641,15 @@
 	}
 }
 
-func (b *BrowseTools) scrollIntoViewRun(ctx context.Context, m json.RawMessage) ([]llm.Content, error) {
+func (b *BrowseTools) scrollIntoViewRun(ctx context.Context, m json.RawMessage) llm.ToolOut {
 	var input scrollIntoViewInput
 	if err := json.Unmarshal(m, &input); err != nil {
-		return nil, fmt.Errorf("invalid input: %w", err)
+		return llm.ErrorfToolOut("invalid input: %w", err)
 	}
 
 	browserCtx, err := b.GetBrowserContext()
 	if err != nil {
-		return nil, err
+		return llm.ErrorToolOut(err)
 	}
 
 	// Create a timeout context for this operation
@@ -671,14 +671,14 @@
 		chromedp.Evaluate(script, &result),
 	)
 	if err != nil {
-		return nil, err
+		return llm.ErrorToolOut(err)
 	}
 
 	if !result {
-		return nil, fmt.Errorf("element not found: %s", input.Selector)
+		return llm.ErrorToolOut(fmt.Errorf("element not found: %s", input.Selector))
 	}
 
-	return llm.TextContent("done"), nil
+	return llm.ToolOut{LLMContent: llm.TextContent("done")}
 }
 
 // ResizeTool definition
@@ -715,15 +715,15 @@
 	}
 }
 
-func (b *BrowseTools) resizeRun(ctx context.Context, m json.RawMessage) ([]llm.Content, error) {
+func (b *BrowseTools) resizeRun(ctx context.Context, m json.RawMessage) llm.ToolOut {
 	var input resizeInput
 	if err := json.Unmarshal(m, &input); err != nil {
-		return nil, fmt.Errorf("invalid input: %w", err)
+		return llm.ErrorfToolOut("invalid input: %w", err)
 	}
 
 	browserCtx, err := b.GetBrowserContext()
 	if err != nil {
-		return nil, err
+		return llm.ErrorToolOut(err)
 	}
 
 	// Create a timeout context for this operation
@@ -732,7 +732,7 @@
 
 	// Validate dimensions
 	if input.Width <= 0 || input.Height <= 0 {
-		return nil, fmt.Errorf("invalid dimensions: width and height must be positive")
+		return llm.ErrorToolOut(fmt.Errorf("invalid dimensions: width and height must be positive"))
 	}
 
 	// Resize the browser window
@@ -740,10 +740,10 @@
 		chromedp.EmulateViewport(int64(input.Width), int64(input.Height)),
 	)
 	if err != nil {
-		return nil, err
+		return llm.ErrorToolOut(err)
 	}
 
-	return llm.TextContent("done"), nil
+	return llm.ToolOut{LLMContent: llm.TextContent("done")}
 }
 
 // GetTools returns browser tools, optionally filtering out screenshot-related tools
@@ -824,34 +824,34 @@
 	}
 }
 
-func (b *BrowseTools) readImageRun(ctx context.Context, m json.RawMessage) ([]llm.Content, error) {
+func (b *BrowseTools) readImageRun(ctx context.Context, m json.RawMessage) llm.ToolOut {
 	var input readImageInput
 	if err := json.Unmarshal(m, &input); err != nil {
-		return nil, fmt.Errorf("invalid input: %w", err)
+		return llm.ErrorfToolOut("invalid input: %w", err)
 	}
 
 	// Check if the path exists
 	if _, err := os.Stat(input.Path); os.IsNotExist(err) {
-		return nil, fmt.Errorf("image file not found: %s", input.Path)
+		return llm.ErrorfToolOut("image file not found: %s", input.Path)
 	}
 
 	// Read the file
 	imageData, err := os.ReadFile(input.Path)
 	if err != nil {
-		return nil, fmt.Errorf("failed to read image file: %w", err)
+		return llm.ErrorfToolOut("failed to read image file: %w", err)
 	}
 
 	// Detect the image type
 	imageType := http.DetectContentType(imageData)
 	if !strings.HasPrefix(imageType, "image/") {
-		return nil, fmt.Errorf("file is not an image: %s", imageType)
+		return llm.ErrorfToolOut("file is not an image: %s", imageType)
 	}
 
 	// Encode the image as base64
 	base64Data := base64.StdEncoding.EncodeToString(imageData)
 
 	// Create a Content object that includes both text and the image
-	return []llm.Content{
+	return llm.ToolOut{LLMContent: []llm.Content{
 		{
 			Type: llm.ContentTypeText,
 			Text: fmt.Sprintf("Image from %s (type: %s)", input.Path, imageType),
@@ -861,7 +861,7 @@
 			MediaType: imageType,
 			Data:      base64Data,
 		},
-	}, nil
+	}}
 }
 
 // parseTimeout parses a timeout string and returns a time.Duration
@@ -916,16 +916,16 @@
 	}
 }
 
-func (b *BrowseTools) recentConsoleLogsRun(ctx context.Context, m json.RawMessage) ([]llm.Content, error) {
+func (b *BrowseTools) recentConsoleLogsRun(ctx context.Context, m json.RawMessage) llm.ToolOut {
 	var input recentConsoleLogsInput
 	if err := json.Unmarshal(m, &input); err != nil {
-		return nil, fmt.Errorf("invalid input: %w", err)
+		return llm.ErrorfToolOut("invalid input: %w", err)
 	}
 
 	// Ensure browser is initialized
 	_, err := b.GetBrowserContext()
 	if err != nil {
-		return nil, err
+		return llm.ErrorToolOut(err)
 	}
 
 	// Apply limit (default to 100 if not specified)
@@ -947,7 +947,7 @@
 	// Format the logs as JSON
 	logData, err := json.MarshalIndent(logs, "", "  ")
 	if err != nil {
-		return nil, fmt.Errorf("failed to serialize logs: %w", err)
+		return llm.ErrorfToolOut("failed to serialize logs: %w", err)
 	}
 
 	// Format the logs
@@ -961,7 +961,7 @@
 		sb.WriteString(string(logData))
 	}
 
-	return llm.TextContent(sb.String()), nil
+	return llm.ToolOut{LLMContent: llm.TextContent(sb.String())}
 }
 
 // ClearConsoleLogsTool definition
@@ -977,16 +977,16 @@
 	}
 }
 
-func (b *BrowseTools) clearConsoleLogsRun(ctx context.Context, m json.RawMessage) ([]llm.Content, error) {
+func (b *BrowseTools) clearConsoleLogsRun(ctx context.Context, m json.RawMessage) llm.ToolOut {
 	var input clearConsoleLogsInput
 	if err := json.Unmarshal(m, &input); err != nil {
-		return nil, fmt.Errorf("invalid input: %w", err)
+		return llm.ErrorfToolOut("invalid input: %w", err)
 	}
 
 	// Ensure browser is initialized
 	_, err := b.GetBrowserContext()
 	if err != nil {
-		return nil, err
+		return llm.ErrorToolOut(err)
 	}
 
 	// Clear console logs with mutex protection
@@ -995,5 +995,5 @@
 	b.consoleLogs = make([]*runtime.EventConsoleAPICalled, 0)
 	b.consoleLogsMutex.Unlock()
 
-	return llm.TextContent(fmt.Sprintf("Cleared %d console log entries.", logCount)), nil
+	return llm.ToolOut{LLMContent: llm.TextContent(fmt.Sprintf("Cleared %d console log entries.", logCount))}
 }
diff --git a/claudetool/browse/browse_test.go b/claudetool/browse/browse_test.go
index ff17055..d1b1eec 100644
--- a/claudetool/browse/browse_test.go
+++ b/claudetool/browse/browse_test.go
@@ -177,10 +177,11 @@
 	inputJSON, _ := json.Marshal(input)
 
 	// Call the tool
-	result, err := navTool.Run(ctx, json.RawMessage(inputJSON))
-	if err != nil {
-		t.Fatalf("Error running navigate tool: %v", err)
+	toolOut := navTool.Run(ctx, json.RawMessage(inputJSON))
+	if toolOut.Error != nil {
+		t.Fatalf("Error running navigate tool: %v", toolOut.Error)
 	}
+	result := toolOut.LLMContent
 
 	// Verify the response is successful
 	resultText := result[0].Text
@@ -288,10 +289,11 @@
 	input := fmt.Sprintf(`{"path": "%s"}`, testImagePath)
 
 	// Run the tool
-	result, err := readImageTool.Run(ctx, json.RawMessage(input))
-	if err != nil {
-		t.Fatalf("Read image tool failed: %v", err)
+	toolOut := readImageTool.Run(ctx, json.RawMessage(input))
+	if toolOut.Error != nil {
+		t.Fatalf("Read image tool failed: %v", toolOut.Error)
 	}
+	result := toolOut.LLMContent
 
 	// In the updated code, result is already a []llm.Content
 	contents := result
@@ -338,20 +340,22 @@
 
 	// Navigate to a simple page to ensure the browser is ready
 	navInput := json.RawMessage(`{"url": "about:blank"}`)
-	content, err := tools.NewNavigateTool().Run(ctx, navInput)
-	if err != nil {
-		t.Fatalf("Navigation error: %v", err)
+	toolOut := tools.NewNavigateTool().Run(ctx, navInput)
+	if toolOut.Error != nil {
+		t.Fatalf("Navigation error: %v", toolOut.Error)
 	}
+	content := toolOut.LLMContent
 	if !strings.Contains(content[0].Text, "done") {
 		t.Fatalf("Expected done in navigation response, got: %s", content[0].Text)
 	}
 
 	// Check default viewport dimensions via JavaScript
 	evalInput := json.RawMessage(`{"expression": "({width: window.innerWidth, height: window.innerHeight})"}`)
-	content, err = tools.NewEvalTool().Run(ctx, evalInput)
-	if err != nil {
-		t.Fatalf("Evaluation error: %v", err)
+	toolOut = tools.NewEvalTool().Run(ctx, evalInput)
+	if toolOut.Error != nil {
+		t.Fatalf("Evaluation error: %v", toolOut.Error)
 	}
+	content = toolOut.LLMContent
 
 	// Parse the result to verify dimensions
 	var response struct {
@@ -398,30 +402,33 @@
 		// Resize to mobile dimensions
 		resizeTool := tools.NewResizeTool()
 		input := json.RawMessage(`{"width": 375, "height": 667}`)
-		content, err := resizeTool.Run(ctx, input)
-		if err != nil {
-			t.Fatalf("Error: %v", err)
+		toolOut := resizeTool.Run(ctx, input)
+		if toolOut.Error != nil {
+			t.Fatalf("Error: %v", toolOut.Error)
 		}
+		content := toolOut.LLMContent
 		if !strings.Contains(content[0].Text, "done") {
 			t.Fatalf("Expected done in response, got: %s", content[0].Text)
 		}
 
 		// Navigate to a test page and verify using JavaScript to get window dimensions
 		navInput := json.RawMessage(`{"url": "https://example.com"}`)
-		content, err = tools.NewNavigateTool().Run(ctx, navInput)
-		if err != nil {
-			t.Fatalf("Error: %v", err)
+		toolOut = tools.NewNavigateTool().Run(ctx, navInput)
+		if toolOut.Error != nil {
+			t.Fatalf("Error: %v", toolOut.Error)
 		}
+		content = toolOut.LLMContent
 		if !strings.Contains(content[0].Text, "done") {
 			t.Fatalf("Expected done in response, got: %s", content[0].Text)
 		}
 
 		// Check dimensions via JavaScript
 		evalInput := json.RawMessage(`{"expression": "({width: window.innerWidth, height: window.innerHeight})"}`)
-		content, err = tools.NewEvalTool().Run(ctx, evalInput)
-		if err != nil {
-			t.Fatalf("Error: %v", err)
+		toolOut = tools.NewEvalTool().Run(ctx, evalInput)
+		if toolOut.Error != nil {
+			t.Fatalf("Error: %v", toolOut.Error)
 		}
+		content = toolOut.LLMContent
 
 		// The dimensions might not be exactly what we set (browser chrome, etc.)
 		// but they should be close