feat: enhance system prompt with app context and dynamic model name

- Add App Context section describing the left/right panel layout
- Add App Features section with icon locations (history, theme, upload, export, clear)
- Dynamically inject model name into system prompt via {{MODEL_NAME}} placeholder
- Expand edit_diagram tool description with usage guidelines

.gitignore

@@ -41,3 +41,4 @@ yarn-error.log*
 next-env.d.ts
 push-via-ec2.sh
 .claude/settings.local.json
+.playwright-mcp/

LICENSE

@@ -0,0 +1,190 @@
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+
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+   See the License for the specific language governing permissions and
+   limitations under the License.

README.md

@@ -81,7 +81,7 @@ Diagrams are represented as XML that can be rendered in draw.io. The AI processe
 ## Multi-Provider Support
 
 -   AWS Bedrock (default)
--   OpenAI / OpenAI-compatible APIs (via `OPENAI_BASE_URL`)
+-   OpenAI
 -   Anthropic
 -   Google AI
 -   Azure OpenAI
@@ -89,6 +89,12 @@ Diagrams are represented as XML that can be rendered in draw.io. The AI processe
 -   OpenRouter
 -   DeepSeek
 
+All providers except AWS Bedrock and OpenRouter support custom endpoints.
+
+📖 **[Detailed Provider Configuration Guide](./docs/ai-providers.md)** - See setup instructions for each provider.
+
+**Model Requirements**: This task requires strong model capabilities for generating long-form text with strict formatting constraints (draw.io XML). Recommended models include Claude Sonnet 4.5, GPT-4o, Gemini 2.0, and DeepSeek V3/R1.
+
 Note that `claude-sonnet-4-5` has trained on draw.io diagrams with AWS logos, so if you want to create AWS architecture diagrams, this is the best choice.
 
 ## Getting Started
@@ -143,8 +149,11 @@ Edit `.env.local` and configure your chosen provider:
 -   Set `AI_PROVIDER` to your chosen provider (bedrock, openai, anthropic, google, azure, ollama, openrouter, deepseek)
 -   Set `AI_MODEL` to the specific model you want to use
 -   Add the required API keys for your provider
+-   `ACCESS_CODE_LIST`: Optional access password(s), can be comma-separated for multiple passwords.
 
-See the [Multi-Provider Support](#multi-provider-support) section above for provider-specific configuration examples.
+> Warning: If you do not set `ACCESS_CODE_LIST`, anyone can access your deployed site directly, which may lead to rapid depletion of your token. It is recommended to set this option.
+
+See the [Provider Configuration Guide](./docs/ai-providers.md) for detailed setup instructions for each provider.
 
 4. Run the development server:
 

README_CN.md

@@ -81,7 +81,7 @@ https://github.com/user-attachments/assets/b2eef5f3-b335-4e71-a755-dc2e80931979
 ## 多提供商支持
 
 -   AWS Bedrock（默认）
--   OpenAI / OpenAI兼容API（通过 `OPENAI_BASE_URL`）
+-   OpenAI
 -   Anthropic
 -   Google AI
 -   Azure OpenAI
@@ -89,6 +89,12 @@ https://github.com/user-attachments/assets/b2eef5f3-b335-4e71-a755-dc2e80931979
 -   OpenRouter
 -   DeepSeek
 
+除AWS Bedrock和OpenRouter外，所有提供商都支持自定义端点。
+
+📖 **[详细的提供商配置指南](./docs/ai-providers.md)** - 查看各提供商的设置说明。
+
+**模型要求**：此任务需要强大的模型能力，因为它涉及生成具有严格格式约束的长文本（draw.io XML）。推荐使用Claude Sonnet 4.5、GPT-4o、Gemini 2.0和DeepSeek V3/R1。
+
 注意：`claude-sonnet-4-5` 已在带有AWS标志的draw.io图表上进行训练，因此如果您想创建AWS架构图，这是最佳选择。
 
 ## 快速开始
@@ -143,8 +149,11 @@ cp env.example .env.local
 -   将 `AI_PROVIDER` 设置为您选择的提供商（bedrock, openai, anthropic, google, azure, ollama, openrouter, deepseek）
 -   将 `AI_MODEL` 设置为您要使用的特定模型
 -   添加您的提供商所需的API密钥
+-   `ACCESS_CODE_LIST` 访问密码，可选，可以使用逗号隔开多个密码。
 
-请参阅上面的[多提供商支持](#多提供商支持)部分了解特定提供商的配置示例。
+> 警告：如果不填写 `ACCESS_CODE_LIST`，则任何人都可以直接使用你部署后的网站，可能会导致你的 token 被急速消耗完毕，建议填写此选项。
+
+详细设置说明请参阅[提供商配置指南](./docs/ai-providers.md)。
 
 4. 运行开发服务器：
 

README_JA.md

@@ -81,7 +81,7 @@ https://github.com/user-attachments/assets/b2eef5f3-b335-4e71-a755-dc2e80931979
 ## マルチプロバイダーサポート
 
 -   AWS Bedrock（デフォルト）
--   OpenAI / OpenAI互換API（`OPENAI_BASE_URL`経由）
+-   OpenAI
 -   Anthropic
 -   Google AI
 -   Azure OpenAI
@@ -89,6 +89,12 @@ https://github.com/user-attachments/assets/b2eef5f3-b335-4e71-a755-dc2e80931979
 -   OpenRouter
 -   DeepSeek
 
+AWS BedrockとOpenRouter以外のすべてのプロバイダーはカスタムエンドポイントをサポートしています。
+
+📖 **[詳細なプロバイダー設定ガイド](./docs/ai-providers.md)** - 各プロバイダーの設定手順をご覧ください。
+
+**モデル要件**：このタスクは厳密なフォーマット制約（draw.io XML）を持つ長文テキスト生成を伴うため、強力なモデル機能が必要です。Claude Sonnet 4.5、GPT-4o、Gemini 2.0、DeepSeek V3/R1を推奨します。
+
 注：`claude-sonnet-4-5`はAWSロゴ付きのdraw.ioダイアグラムで学習されているため、AWSアーキテクチャダイアグラムを作成したい場合は最適な選択です。
 
 ## はじめに
@@ -143,8 +149,11 @@ cp env.example .env.local
 -   `AI_PROVIDER`を選択したプロバイダーに設定（bedrock, openai, anthropic, google, azure, ollama, openrouter, deepseek）
 -   `AI_MODEL`を使用する特定のモデルに設定
 -   プロバイダーに必要なAPIキーを追加
+-   `ACCESS_CODE_LIST` アクセスパスワード（オプション）。カンマ区切りで複数のパスワードを指定できます。
 
-プロバイダー固有の設定例については、上記の[マルチプロバイダーサポート](#マルチプロバイダーサポート)セクションを参照してください。
+> 警告：`ACCESS_CODE_LIST`を設定しない場合、誰でもデプロイされたサイトに直接アクセスできるため、トークンが急速に消費される可能性があります。このオプションを設定することをお勧めします。
+
+詳細な設定手順については[プロバイダー設定ガイド](./docs/ai-providers.md)を参照してください。
 
 4. 開発サーバーを起動：
 

amplify.yml

@@ -0,0 +1,22 @@
+version: 1
+frontend:
+  phases:
+    preBuild:
+      commands:
+        - npm ci --cache .npm --prefer-offline
+    build:
+      commands:
+        # Write env vars to .env.production for Next.js SSR runtime
+        - env | grep -e AI_MODEL >> .env.production
+        - env | grep -e AI_PROVIDER >> .env.production
+        - env | grep -e OPENAI_API_KEY >> .env.production
+        - env | grep -e NEXT_PUBLIC_ >> .env.production
+        - npm run build
+  artifacts:
+    baseDirectory: .next
+    files:
+      - '**/*'
+  cache:
+    paths:
+      - .next/cache/**/*
+      - .npm/**/*

app/api/chat/route.ts

@@ -1,10 +1,42 @@
 import { streamText, convertToModelMessages, createUIMessageStream, createUIMessageStreamResponse } from 'ai';
 import { getAIModel } from '@/lib/ai-providers';
 import { findCachedResponse } from '@/lib/cached-responses';
+import { setTraceInput, setTraceOutput, getTelemetryConfig, wrapWithObserve } from '@/lib/langfuse';
+import { getSystemPrompt } from '@/lib/system-prompts';
 import { z } from "zod";
 
 export const maxDuration = 300;
 
+// File upload limits (must match client-side)
+const MAX_FILE_SIZE = 2 * 1024 * 1024; // 2MB
+const MAX_FILES = 5;
+
+// Helper function to validate file parts in messages
+function validateFileParts(messages: any[]): { valid: boolean; error?: string } {
+  const lastMessage = messages[messages.length - 1];
+  const fileParts = lastMessage?.parts?.filter((p: any) => p.type === 'file') || [];
+
+  if (fileParts.length > MAX_FILES) {
+    return { valid: false, error: `Too many files. Maximum ${MAX_FILES} allowed.` };
+  }
+
+  for (const filePart of fileParts) {
+    // Data URLs format: data:image/png;base64,<data>
+    // Base64 increases size by ~33%, so we check the decoded size
+    if (filePart.url && filePart.url.startsWith('data:')) {
+      const base64Data = filePart.url.split(',')[1];
+      if (base64Data) {
+        const sizeInBytes = Math.ceil((base64Data.length * 3) / 4);
+        if (sizeInBytes > MAX_FILE_SIZE) {
+          return { valid: false, error: `File exceeds ${MAX_FILE_SIZE / 1024 / 1024}MB limit.` };
+        }
+      }
+    }
+  }
+
+  return { valid: true };
+}
+
 // Helper function to check if diagram is minimal/empty
 function isMinimalDiagram(xml: string): boolean {
   const stripped = xml.replace(/\s/g, '');
@@ -28,266 +60,188 @@ function createCachedStreamResponse(xml: string): Response {
   return createUIMessageStreamResponse({ stream });
 }
 
-export async function POST(req: Request) {
-  try {
-    const { messages, xml, sessionId } = await req.json();
-
-    // Get user IP for Langfuse tracking
-    const forwardedFor = req.headers.get('x-forwarded-for');
-    const userId = forwardedFor?.split(',')[0]?.trim() || 'anonymous';
-
-    // Validate sessionId for Langfuse (must be string, max 200 chars)
-    const validSessionId = sessionId && typeof sessionId === 'string' && sessionId.length <= 200
-      ? sessionId
-      : undefined;
-
-    // === CACHE CHECK START ===
-    const isFirstMessage = messages.length === 1;
-    const isEmptyDiagram = !xml || xml.trim() === '' || isMinimalDiagram(xml);
-
-    if (isFirstMessage && isEmptyDiagram) {
-      const lastMessage = messages[0];
-      const textPart = lastMessage.parts?.find((p: any) => p.type === 'text');
-      const filePart = lastMessage.parts?.find((p: any) => p.type === 'file');
-
-      const cached = findCachedResponse(textPart?.text || '', !!filePart);
-
-      if (cached) {
-        console.log('[Cache] Returning cached response for:', textPart?.text);
-        return createCachedStreamResponse(cached.xml);
-      }
+// Inner handler function
+async function handleChatRequest(req: Request): Promise<Response> {
+  // Check for access code
+  const accessCodes = process.env.ACCESS_CODE_LIST?.split(',').map(code => code.trim()).filter(Boolean) || [];
+  if (accessCodes.length > 0) {
+    const accessCodeHeader = req.headers.get('x-access-code');
+    if (!accessCodeHeader || !accessCodes.includes(accessCodeHeader)) {
+      return Response.json(
+        { error: 'Invalid or missing access code. Please configure it in Settings.' },
+        { status: 401 }
+      );
     }
-    // === CACHE CHECK END ===
+  }
 
-    const systemMessage = `
-You are an expert diagram creation assistant specializing in draw.io XML generation.
-Your primary function is chat with user and crafting clear, well-organized visual diagrams through precise XML specifications.
-You can see the image that user uploaded.
+  const { messages, xml, sessionId } = await req.json();
 
-You utilize the following tools:
----Tool1---
-tool name: display_diagram
-description: Display a NEW diagram on draw.io. Use this when creating a diagram from scratch or when major structural changes are needed.
-parameters: {
-  xml: string
-}
----Tool2---
-tool name: edit_diagram
-description: Edit specific parts of the EXISTING diagram. Use this when making small targeted changes like adding/removing elements, changing labels, or adjusting properties. This is more efficient than regenerating the entire diagram.
-parameters: {
-  edits: Array<{search: string, replace: string}>
-}
----End of tools---
+  // Get user IP for Langfuse tracking
+  const forwardedFor = req.headers.get('x-forwarded-for');
+  const userId = forwardedFor?.split(',')[0]?.trim() || 'anonymous';
 
-IMPORTANT: Choose the right tool:
-- Use display_diagram for: Creating new diagrams, major restructuring, or when the current diagram XML is empty
-- Use edit_diagram for: Small modifications, adding/removing elements, changing text/colors, repositioning items
+  // Validate sessionId for Langfuse (must be string, max 200 chars)
+  const validSessionId = sessionId && typeof sessionId === 'string' && sessionId.length <= 200
+    ? sessionId
+    : undefined;
 
-Core capabilities:
-- Generate valid, well-formed XML strings for draw.io diagrams
-- Create professional flowcharts, mind maps, entity diagrams, and technical illustrations
-- Convert user descriptions into visually appealing diagrams using basic shapes and connectors
-- Apply proper spacing, alignment and visual hierarchy in diagram layouts
-- Adapt artistic concepts into abstract diagram representations using available shapes
-- Optimize element positioning to prevent overlapping and maintain readability
-- Structure complex systems into clear, organized visual components
+  // Extract user input text for Langfuse trace
+  const currentMessage = messages[messages.length - 1];
+  const userInputText = currentMessage?.parts?.find((p: any) => p.type === 'text')?.text || '';
 
-Layout constraints:
-- CRITICAL: Keep all diagram elements within a single page viewport to avoid page breaks
-- Position all elements with x coordinates between 0-800 and y coordinates between 0-600
-- Maximum width for containers (like AWS cloud boxes): 700 pixels
-- Maximum height for containers: 550 pixels
-- Use compact, efficient layouts that fit the entire diagram in one view
-- Start positioning from reasonable margins (e.g., x=40, y=40) and keep elements grouped closely
-- For large diagrams with many elements, use vertical stacking or grid layouts that stay within bounds
-- Avoid spreading elements too far apart horizontally - users should see the complete diagram without a page break line
+  // Update Langfuse trace with input, session, and user
+  setTraceInput({
+    input: userInputText,
+    sessionId: validSessionId,
+    userId: userId,
+  });
 
-Note that:
-- Use proper tool calls to generate or edit diagrams;
-  - never return raw XML in text responses,
-  - never use display_diagram to generate messages that you want to send user directly. e.g. to generate a "hello" text box when you want to greet user.
-- Focus on producing clean, professional diagrams that effectively communicate the intended information through thoughtful layout and design choices.
-- When artistic drawings are requested, creatively compose them using standard diagram shapes and connectors while maintaining visual clarity.
-- Return XML only via tool calls, never in text responses.
-- If user asks you to replicate a diagram based on an image, remember to match the diagram style and layout as closely as possible. Especially, pay attention to the lines and shapes, for example, if the lines are straight or curved, and if the shapes are rounded or square.
-- Note that when you need to generate diagram about aws architecture, use **AWS 2025 icons**.
+  // === FILE VALIDATION START ===
+  const fileValidation = validateFileParts(messages);
+  if (!fileValidation.valid) {
+    return Response.json({ error: fileValidation.error }, { status: 400 });
+  }
+  // === FILE VALIDATION END ===
 
-When using edit_diagram tool:
-- Keep edits minimal - only include the specific line being changed plus 1-2 context lines
-- Example GOOD edit: {"search": "  <mxCell id=\"2\" value=\"Old Text\">", "replace": "  <mxCell id=\"2\" value=\"New Text\">"}
-- Example BAD edit: Including 10+ unchanged lines just to change one attribute
-- For multiple changes, use separate edits: [{"search": "line1", "replace": "new1"}, {"search": "line2", "replace": "new2"}]
-- RETRY POLICY: If edit_diagram fails because the search pattern cannot be found:
-  * You may retry edit_diagram up to 3 times with adjusted search patterns
-  * After 3 failed attempts, you MUST fall back to using display_diagram to regenerate the entire diagram
-  * The error message will indicate how many retries remain
+  // === CACHE CHECK START ===
+  const isFirstMessage = messages.length === 1;
+  const isEmptyDiagram = !xml || xml.trim() === '' || isMinimalDiagram(xml);
 
-## Draw.io XML Structure Reference
+  if (isFirstMessage && isEmptyDiagram) {
+    const lastMessage = messages[0];
+    const textPart = lastMessage.parts?.find((p: any) => p.type === 'text');
+    const filePart = lastMessage.parts?.find((p: any) => p.type === 'file');
 
-Basic structure:
-\`\`\`xml
-<mxGraphModel>
-  <root>
-    <mxCell id="0"/>
-    <mxCell id="1" parent="0"/>
-    <!-- All other cells go here as siblings -->
-  </root>
-</mxGraphModel>
-\`\`\`
+    const cached = findCachedResponse(textPart?.text || '', !!filePart);
 
-CRITICAL RULES:
-1. Always include the two root cells: <mxCell id="0"/> and <mxCell id="1" parent="0"/>
-2. ALL mxCell elements must be DIRECT children of <root> - NEVER nest mxCell inside another mxCell
-3. Use unique sequential IDs for all cells (start from "2" for user content)
-4. Set parent="1" for top-level shapes, or parent="<container-id>" for grouped elements
+    if (cached) {
+      console.log('[Cache] Returning cached response for:', textPart?.text);
+      return createCachedStreamResponse(cached.xml);
+    }
+  }
+  // === CACHE CHECK END ===
 
-Shape (vertex) example:
-\`\`\`xml
-<mxCell id="2" value="Label" style="rounded=1;whiteSpace=wrap;html=1;" vertex="1" parent="1">
-  <mxGeometry x="100" y="100" width="120" height="60" as="geometry"/>
-</mxCell>
-\`\`\`
+  // Get AI model from environment configuration
+  const { model, providerOptions, headers, modelId } = getAIModel();
 
-Connector (edge) example:
-\`\`\`xml
-<mxCell id="3" style="endArrow=classic;html=1;" edge="1" parent="1" source="2" target="4">
-  <mxGeometry relative="1" as="geometry"/>
-</mxCell>
-\`\`\`
+  // Get the appropriate system prompt based on model (extended for Opus/Haiku 4.5)
+  const systemMessage = getSystemPrompt(modelId);
 
-Common styles:
-- Shapes: rounded=1 (rounded corners), fillColor=#hex, strokeColor=#hex
-- Edges: endArrow=classic/block/open/none, startArrow=none/classic, curved=1, edgeStyle=orthogonalEdgeStyle
-- Text: fontSize=14, fontStyle=1 (bold), align=center/left/right
-`;
+  const lastMessage = messages[messages.length - 1];
 
-    const lastMessage = messages[messages.length - 1];
+  // Extract text from the last message parts
+  const lastMessageText = lastMessage.parts?.find((part: any) => part.type === 'text')?.text || '';
 
-    // Extract text from the last message parts
-    const lastMessageText = lastMessage.parts?.find((part: any) => part.type === 'text')?.text || '';
+  // Extract file parts (images) from the last message
+  const fileParts = lastMessage.parts?.filter((part: any) => part.type === 'file') || [];
 
-    // Extract file parts (images) from the last message
-    const fileParts = lastMessage.parts?.filter((part: any) => part.type === 'file') || [];
-
-    const formattedTextContent = `
-Current diagram XML:
-"""xml
-${xml || ''}
-"""
-User input:
+  // User input only - XML is now in a separate cached system message
+  const formattedUserInput = `User input:
 """md
 ${lastMessageText}
 """`;
 
-    // Convert UIMessages to ModelMessages and add system message
-    const modelMessages = convertToModelMessages(messages);
+  // Convert UIMessages to ModelMessages and add system message
+  const modelMessages = convertToModelMessages(messages);
 
-    // Log messages with empty content for debugging (helps identify root cause)
-    const emptyMessages = modelMessages.filter((msg: any) =>
-      !msg.content || !Array.isArray(msg.content) || msg.content.length === 0
-    );
-    if (emptyMessages.length > 0) {
-      console.warn('[Chat API] Messages with empty content detected:',
-        JSON.stringify(emptyMessages.map((m: any) => ({ role: m.role, contentLength: m.content?.length })))
-      );
-      console.warn('[Chat API] Original UI messages structure:',
-        JSON.stringify(messages.map((m: any) => ({
-          id: m.id,
-          role: m.role,
-          partsCount: m.parts?.length,
-          partTypes: m.parts?.map((p: any) => p.type)
-        })))
-      );
+  // Filter out messages with empty content arrays (Bedrock API rejects these)
+  // This is a safety measure - ideally convertToModelMessages should handle all cases
+  let enhancedMessages = modelMessages.filter((msg: any) =>
+    msg.content && Array.isArray(msg.content) && msg.content.length > 0
+  );
+
+  // Update the last message with user input only (XML moved to separate cached system message)
+  if (enhancedMessages.length >= 1) {
+    const lastModelMessage = enhancedMessages[enhancedMessages.length - 1];
+    if (lastModelMessage.role === 'user') {
+      // Build content array with user input text and file parts
+      const contentParts: any[] = [
+        { type: 'text', text: formattedUserInput }
+      ];
+
+      // Add image parts back
+      for (const filePart of fileParts) {
+        contentParts.push({
+          type: 'image',
+          image: filePart.url,
+          mimeType: filePart.mediaType
+        });
+      }
+
+      enhancedMessages = [
+        ...enhancedMessages.slice(0, -1),
+        { ...lastModelMessage, content: contentParts }
+      ];
     }
+  }
 
-    // Filter out messages with empty content arrays (Bedrock API rejects these)
-    // This is a safety measure - ideally convertToModelMessages should handle all cases
-    let enhancedMessages = modelMessages.filter((msg: any) =>
-      msg.content && Array.isArray(msg.content) && msg.content.length > 0
-    );
-
-    // Update the last message with formatted content if it's a user message
-    if (enhancedMessages.length >= 1) {
-      const lastModelMessage = enhancedMessages[enhancedMessages.length - 1];
-      if (lastModelMessage.role === 'user') {
-        // Build content array with text and file parts
-        const contentParts: any[] = [
-          { type: 'text', text: formattedTextContent }
-        ];
-
-        // Add image parts back
-        for (const filePart of fileParts) {
-          contentParts.push({
-            type: 'image',
-            image: filePart.url,
-            mimeType: filePart.mediaType
-          });
-        }
-
-        enhancedMessages = [
-          ...enhancedMessages.slice(0, -1),
-          { ...lastModelMessage, content: contentParts }
-        ];
+  // Add cache point to the last assistant message in conversation history
+  // This caches the entire conversation prefix for subsequent requests
+  // Strategy: system (cached) + history with last assistant (cached) + new user message
+  if (enhancedMessages.length >= 2) {
+    // Find the last assistant message (should be second-to-last, before current user message)
+    for (let i = enhancedMessages.length - 2; i >= 0; i--) {
+      if (enhancedMessages[i].role === 'assistant') {
+        enhancedMessages[i] = {
+          ...enhancedMessages[i],
+          providerOptions: {
+            bedrock: { cachePoint: { type: 'default' } },
+          },
+        };
+        break; // Only cache the last assistant message
       }
     }
+  }
 
-    // Add cache point to the last assistant message in conversation history
-    // This caches the entire conversation prefix for subsequent requests
-    // Strategy: system (cached) + history with last assistant (cached) + new user message
-    if (enhancedMessages.length >= 2) {
-      // Find the last assistant message (should be second-to-last, before current user message)
-      for (let i = enhancedMessages.length - 2; i >= 0; i--) {
-        if (enhancedMessages[i].role === 'assistant') {
-          enhancedMessages[i] = {
-            ...enhancedMessages[i],
-            providerOptions: {
-              bedrock: { cachePoint: { type: 'default' } },
-            },
-          };
-          break; // Only cache the last assistant message
-        }
-      }
-    }
-
-    // Get AI model from environment configuration
-    const { model, providerOptions, headers } = getAIModel();
-
-    // System message with cache point for Bedrock (requires 1024+ tokens)
-    const systemMessageWithCache = {
+  // System messages with multiple cache breakpoints for optimal caching:
+  // - Breakpoint 1: Static instructions (~1500 tokens) - rarely changes
+  // - Breakpoint 2: Current XML context - changes per diagram, but constant within a conversation turn
+  // This allows: if only user message changes, both system caches are reused
+  //              if XML changes, instruction cache is still reused
+  const systemMessages = [
+    // Cache breakpoint 1: Instructions (rarely change)
+    {
       role: 'system' as const,
       content: systemMessage,
       providerOptions: {
         bedrock: { cachePoint: { type: 'default' } },
       },
-    };
-
-    const result = streamText({
-      model,
-      messages: [systemMessageWithCache, ...enhancedMessages],
-      ...(providerOptions && { providerOptions }),
-      ...(headers && { headers }),
-      // Only enable telemetry if Langfuse is configured
-      ...(process.env.LANGFUSE_PUBLIC_KEY && {
-        experimental_telemetry: {
-          isEnabled: true,
-          metadata: {
-            sessionId: validSessionId,
-            userId: userId,
-          },
-        },
-      }),
-      onFinish: ({ usage, providerMetadata }) => {
-        console.log('[Cache] Usage:', JSON.stringify({
-          inputTokens: usage?.inputTokens,
-          outputTokens: usage?.outputTokens,
-          cachedInputTokens: usage?.cachedInputTokens,
-        }, null, 2));
-        console.log('[Cache] Provider metadata:', JSON.stringify(providerMetadata, null, 2));
+    },
+    // Cache breakpoint 2: Current diagram XML context
+    {
+      role: 'system' as const,
+      content: `Current diagram XML:\n"""xml\n${xml || ''}\n"""\nWhen using edit_diagram, COPY search patterns exactly from this XML - attribute order matters!`,
+      providerOptions: {
+        bedrock: { cachePoint: { type: 'default' } },
       },
-      tools: {
-        // Client-side tool that will be executed on the client
-        display_diagram: {
-          description: `Display a diagram on draw.io. Pass the XML content inside <root> tags.
+    },
+  ];
+
+  const allMessages = [...systemMessages, ...enhancedMessages];
+
+  const result = streamText({
+    model,
+    messages: allMessages,
+    ...(providerOptions && { providerOptions }),
+    ...(headers && { headers }),
+    // Langfuse telemetry config (returns undefined if not configured)
+    ...(getTelemetryConfig({ sessionId: validSessionId, userId }) && {
+      experimental_telemetry: getTelemetryConfig({ sessionId: validSessionId, userId }),
+    }),
+    onFinish: ({ text, usage, providerMetadata }) => {
+      console.log('[Cache] Full providerMetadata:', JSON.stringify(providerMetadata, null, 2));
+      console.log('[Cache] Usage:', JSON.stringify(usage, null, 2));
+      // Pass usage to Langfuse (Bedrock streaming doesn't auto-report tokens to telemetry)
+      // AI SDK uses inputTokens/outputTokens, Langfuse expects promptTokens/completionTokens
+      setTraceOutput(text, {
+        promptTokens: usage?.inputTokens,
+        completionTokens: usage?.outputTokens,
+      });
+    },
+    tools: {
+      // Client-side tool that will be executed on the client
+      display_diagram: {
+        description: `Display a diagram on draw.io. Pass the XML content inside <root> tags.
 
 VALIDATION RULES (XML will be rejected if violated):
 1. All mxCell elements must be DIRECT children of <root> - never nested
@@ -322,58 +276,64 @@ Notes:
 - For AWS diagrams, use **AWS 2025 icons**.
 - For animated connectors, add "flowAnimation=1" to edge style.
 `,
-          inputSchema: z.object({
-            xml: z.string().describe("XML string to be displayed on draw.io")
-          })
-        },
-        edit_diagram: {
-          description: `Edit specific parts of the current diagram by replacing exact line matches. Use this tool to make targeted fixes without regenerating the entire XML.
-IMPORTANT: Keep edits concise:
-- Only include the lines that are changing, plus 1-2 surrounding lines for context if needed
-- Break large changes into multiple smaller edits
-- Each search must contain complete lines (never truncate mid-line)
-- First match only - be specific enough to target the right element`,
-          inputSchema: z.object({
-            edits: z.array(z.object({
-              search: z.string().describe("Exact lines to search for (including whitespace and indentation)"),
-              replace: z.string().describe("Replacement lines")
-            })).describe("Array of search/replace pairs to apply sequentially")
-          })
-        },
+        inputSchema: z.object({
+          xml: z.string().describe("XML string to be displayed on draw.io")
+        })
       },
-      temperature: 0,
-    });
+      edit_diagram: {
+        description: `Edit specific parts of the current diagram by replacing exact line matches. Use this tool to make targeted fixes without regenerating the entire XML.
 
-    // Error handler function to provide detailed error messages
-    function errorHandler(error: unknown) {
-      if (error == null) {
-        return 'unknown error';
-      }
+WHEN TO USE:
+- Changing text labels or values
+- Modifying colors, styles, or visual properties
+- Adding or removing individual elements (1-3 elements)
+- Repositioning specific elements
+- Any small, targeted modification
 
-      const errorString = typeof error === 'string'
-        ? error
-        : error instanceof Error
-          ? error.message
-          : JSON.stringify(error);
+WHEN TO USE display_diagram INSTEAD:
+- Creating a new diagram from scratch
+- Major restructuring (reorganizing layout, changing diagram type)
+- Adding many new elements (more than 3)
+- After 3 failed edit_diagram attempts
 
-      // Check for image not supported error (e.g., DeepSeek models)
-      if (errorString.includes('image_url') ||
-          errorString.includes('unknown variant') ||
-          (errorString.includes('image') && errorString.includes('not supported'))) {
-        return 'This model does not support image inputs. Please remove the image and try again, or switch to a vision-capable model.';
-      }
+CRITICAL RULES:
+1. Copy-paste the EXACT search pattern from the "Current diagram XML" in system context
+2. Do NOT reorder attributes - attribute order in draw.io XML varies, you MUST match exactly
+3. Always include the element's id attribute for unique targeting
+4. Include complete lines (never truncate mid-line)
+5. For multiple changes, use separate edits in the array
 
-      return errorString;
-    }
+ERROR RECOVERY:
+- If pattern not found, check attribute order matches current XML exactly
+- Retry up to 3 times with adjusted patterns
+- After 3 failures, use display_diagram instead`,
+        inputSchema: z.object({
+          edits: z.array(z.object({
+            search: z.string().describe("EXACT lines copied from current XML (preserve attribute order!)"),
+            replace: z.string().describe("Replacement lines")
+          })).describe("Array of search/replace pairs to apply sequentially")
+        })
+      },
+    },
+    temperature: 0,
+  });
 
-    return result.toUIMessageStreamResponse({
-      onError: errorHandler,
-    });
+  return result.toUIMessageStreamResponse();
+}
+
+// Wrap handler with error handling
+async function safeHandler(req: Request): Promise<Response> {
+  try {
+    return await handleChatRequest(req);
   } catch (error) {
     console.error('Error in chat route:', error);
-    return Response.json(
-      { error: 'Internal server error' },
-      { status: 500 }
-    );
+    return Response.json({ error: 'Internal server error' }, { status: 500 });
   }
 }
+
+// Wrap with Langfuse observe (if configured)
+const observedHandler = wrapWithObserve(safeHandler);
+
+export async function POST(req: Request) {
+  return observedHandler(req);
+}

app/api/config/route.ts

@@ -0,0 +1,9 @@
+import { NextResponse } from "next/server";
+
+export async function GET() {
+  const accessCodes = process.env.ACCESS_CODE_LIST?.split(',').map(code => code.trim()).filter(Boolean) || [];
+
+  return NextResponse.json({
+    accessCodeRequired: accessCodes.length > 0,
+  });
+}

app/api/log-feedback/route.ts

@@ -0,0 +1,103 @@
+import { getLangfuseClient } from '@/lib/langfuse';
+import { randomUUID } from 'crypto';
+import { z } from 'zod';
+
+const feedbackSchema = z.object({
+  messageId: z.string().min(1).max(200),
+  feedback: z.enum(['good', 'bad']),
+  sessionId: z.string().min(1).max(200).optional(),
+});
+
+export async function POST(req: Request) {
+  const langfuse = getLangfuseClient();
+  if (!langfuse) {
+    return Response.json({ success: true, logged: false });
+  }
+
+  // Validate input
+  let data;
+  try {
+    data = feedbackSchema.parse(await req.json());
+  } catch {
+    return Response.json({ success: false, error: 'Invalid input' }, { status: 400 });
+  }
+
+  const { messageId, feedback, sessionId } = data;
+
+  // Get user IP for tracking
+  const forwardedFor = req.headers.get('x-forwarded-for');
+  const userId = forwardedFor?.split(',')[0]?.trim() || 'anonymous';
+
+  try {
+    // Find the most recent chat trace for this session to attach the score to
+    const tracesResponse = await langfuse.api.trace.list({
+      sessionId,
+      limit: 1,
+    });
+
+    const traces = tracesResponse.data || [];
+    const latestTrace = traces[0];
+
+    if (!latestTrace) {
+      // No trace found for this session - create a standalone feedback trace
+      const traceId = randomUUID();
+      const timestamp = new Date().toISOString();
+
+      await langfuse.api.ingestion.batch({
+        batch: [
+          {
+            type: 'trace-create',
+            id: randomUUID(),
+            timestamp,
+            body: {
+              id: traceId,
+              name: 'user-feedback',
+              sessionId,
+              userId,
+              input: { messageId, feedback },
+              metadata: { source: 'feedback-button', note: 'standalone - no chat trace found' },
+              timestamp,
+            },
+          },
+          {
+            type: 'score-create',
+            id: randomUUID(),
+            timestamp,
+            body: {
+              id: randomUUID(),
+              traceId,
+              name: 'user-feedback',
+              value: feedback === 'good' ? 1 : 0,
+              comment: `User gave ${feedback} feedback`,
+            },
+          },
+        ],
+      });
+    } else {
+      // Attach score to the existing chat trace
+      const timestamp = new Date().toISOString();
+
+      await langfuse.api.ingestion.batch({
+        batch: [
+          {
+            type: 'score-create',
+            id: randomUUID(),
+            timestamp,
+            body: {
+              id: randomUUID(),
+              traceId: latestTrace.id,
+              name: 'user-feedback',
+              value: feedback === 'good' ? 1 : 0,
+              comment: `User gave ${feedback} feedback`,
+            },
+          },
+        ],
+      });
+    }
+
+    return Response.json({ success: true, logged: true });
+  } catch (error) {
+    console.error('Langfuse feedback error:', error);
+    return Response.json({ success: false, error: 'Failed to log feedback' }, { status: 500 });
+  }
+}

app/api/log-save/route.ts

@@ -0,0 +1,65 @@
+import { getLangfuseClient } from '@/lib/langfuse';
+import { randomUUID } from 'crypto';
+import { z } from 'zod';
+
+const saveSchema = z.object({
+  filename: z.string().min(1).max(255),
+  format: z.enum(['drawio', 'png', 'svg']),
+  sessionId: z.string().min(1).max(200).optional(),
+});
+
+export async function POST(req: Request) {
+  const langfuse = getLangfuseClient();
+  if (!langfuse) {
+    return Response.json({ success: true, logged: false });
+  }
+
+  // Validate input
+  let data;
+  try {
+    data = saveSchema.parse(await req.json());
+  } catch {
+    return Response.json({ success: false, error: 'Invalid input' }, { status: 400 });
+  }
+
+  const { filename, format, sessionId } = data;
+
+  try {
+    const timestamp = new Date().toISOString();
+
+    // Find the most recent chat trace for this session to attach the save flag
+    const tracesResponse = await langfuse.api.trace.list({
+      sessionId,
+      limit: 1,
+    });
+
+    const traces = tracesResponse.data || [];
+    const latestTrace = traces[0];
+
+    if (latestTrace) {
+      // Add a score to the existing trace to flag that user saved
+      await langfuse.api.ingestion.batch({
+        batch: [
+          {
+            type: 'score-create',
+            id: randomUUID(),
+            timestamp,
+            body: {
+              id: randomUUID(),
+              traceId: latestTrace.id,
+              name: 'diagram-saved',
+              value: 1,
+              comment: `User saved diagram as ${filename}.${format}`,
+            },
+          },
+        ],
+      });
+    }
+    // If no trace found, skip logging (user hasn't chatted yet)
+
+    return Response.json({ success: true, logged: !!latestTrace });
+  } catch (error) {
+    console.error('Langfuse save error:', error);
+    return Response.json({ success: false, error: 'Failed to log save' }, { status: 500 });
+  }
+}

app/globals.css

@@ -1,6 +1,7 @@
 @import "tailwindcss";
 
 @plugin "tailwindcss-animate";
+@plugin "@tailwindcss/typography";
 
 @custom-variant dark (&:is(.dark *));
 
@@ -152,6 +153,12 @@
   }
 }
 
+/* Fix for Radix ScrollArea viewport horizontal overflow */
+[data-slot="scroll-area-viewport"] > div {
+  display: block !important;
+  width: 100% !important;
+}
+
 /* Custom scrollbar */
 @layer utilities {
   .scrollbar-thin {

app/layout.tsx

@@ -1,4 +1,4 @@
-import type { Metadata } from "next";
+import type { Metadata, Viewport } from "next";
 import { Plus_Jakarta_Sans, JetBrains_Mono } from "next/font/google";
 import { Analytics } from "@vercel/analytics/react";
 import { GoogleAnalytics } from "@next/third-parties/google";
@@ -18,6 +18,13 @@ const jetbrainsMono = JetBrains_Mono({
     weight: ["400", "500"],
 });
 
+export const viewport: Viewport = {
+    width: "device-width",
+    initialScale: 1,
+    maximumScale: 1,
+    userScalable: false,
+};
+
 export const metadata: Metadata = {
     title: "Next AI Draw.io - AI-Powered Diagram Generator",
     description: "Create AWS architecture diagrams, flowcharts, and technical diagrams using AI. Free online tool integrating draw.io with AI assistance for professional diagram creation.",
@@ -96,7 +103,6 @@ export default function RootLayout({
                 className={`${plusJakarta.variable} ${jetbrainsMono.variable} antialiased`}
             >
                 <DiagramProvider>{children}</DiagramProvider>
-
                 <Analytics />
             </body>
             {process.env.NEXT_PUBLIC_GA_ID && (

app/page.tsx

@@ -1,14 +1,27 @@
 "use client";
-import React, { useState, useEffect } from "react";
+import React, { useState, useEffect, useRef } from "react";
 import { DrawIoEmbed } from "react-drawio";
 import ChatPanel from "@/components/chat-panel";
 import { useDiagram } from "@/contexts/diagram-context";
-import { Monitor } from "lucide-react";
+import {
+    ResizablePanelGroup,
+    ResizablePanel,
+    ResizableHandle,
+} from "@/components/ui/resizable";
+import type { ImperativePanelHandle } from "react-resizable-panels";
 
 export default function Home() {
     const { drawioRef, handleDiagramExport } = useDiagram();
     const [isMobile, setIsMobile] = useState(false);
     const [isChatVisible, setIsChatVisible] = useState(true);
+    const [drawioUi, setDrawioUi] = useState<"min" | "sketch">(() => {
+        if (typeof window !== "undefined") {
+            const saved = localStorage.getItem("drawio-theme");
+            if (saved === "min" || saved === "sketch") return saved;
+        }
+        return "min";
+    });
+    const chatPanelRef = useRef<ImperativePanelHandle>(null);
 
     useEffect(() => {
         const checkMobile = () => {
@@ -20,66 +33,99 @@ export default function Home() {
         return () => window.removeEventListener("resize", checkMobile);
     }, []);
 
+    const toggleChatPanel = () => {
+        const panel = chatPanelRef.current;
+        if (panel) {
+            if (panel.isCollapsed()) {
+                panel.expand();
+                setIsChatVisible(true);
+            } else {
+                panel.collapse();
+                setIsChatVisible(false);
+            }
+        }
+    };
+
     useEffect(() => {
         const handleKeyDown = (event: KeyboardEvent) => {
-            if ((event.ctrlKey || event.metaKey) && event.key === 'b') {
+            if ((event.ctrlKey || event.metaKey) && event.key === "b") {
                 event.preventDefault();
-                setIsChatVisible((prev) => !prev);
+                toggleChatPanel();
             }
         };
 
-        window.addEventListener('keydown', handleKeyDown);
-        return () => window.removeEventListener('keydown', handleKeyDown);
+        window.addEventListener("keydown", handleKeyDown);
+        return () => window.removeEventListener("keydown", handleKeyDown);
+    }, []);
+
+    // Show confirmation dialog when user tries to leave the page
+    // This helps prevent accidental navigation from browser back gestures
+    useEffect(() => {
+        const handleBeforeUnload = (event: BeforeUnloadEvent) => {
+            event.preventDefault();
+            return "";
+        };
+
+        window.addEventListener("beforeunload", handleBeforeUnload);
+        return () =>
+            window.removeEventListener("beforeunload", handleBeforeUnload);
     }, []);
 
     return (
-        <div className="flex h-screen bg-background relative overflow-hidden">
-            {/* Mobile warning overlay */}
-            {isMobile && (
-                <div className="absolute inset-0 z-50 flex items-center justify-center bg-background">
-                    <div className="text-center p-8 max-w-sm mx-auto animate-fade-in">
-                        <div className="w-16 h-16 rounded-2xl bg-primary/10 flex items-center justify-center mx-auto mb-6">
-                            <Monitor className="w-8 h-8 text-primary" />
+        <div className="h-screen bg-background relative overflow-hidden">
+            <ResizablePanelGroup
+                key={isMobile ? "mobile" : "desktop"}
+                direction={isMobile ? "vertical" : "horizontal"}
+                className="h-full"
+            >
+                {/* Draw.io Canvas */}
+                <ResizablePanel defaultSize={isMobile ? 50 : 67} minSize={20}>
+                    <div className={`h-full relative ${isMobile ? "p-1" : "p-2"}`}>
+                        <div className="h-full rounded-xl overflow-hidden shadow-soft-lg border border-border/30 bg-white">
+                            <DrawIoEmbed
+                                key={drawioUi}
+                                ref={drawioRef}
+                                onExport={handleDiagramExport}
+                                urlParameters={{
+                                    ui: drawioUi,
+                                    spin: true,
+                                    libraries: false,
+                                    saveAndExit: false,
+                                    noExitBtn: true,
+                                }}
+                            />
                         </div>
-                        <h1 className="text-xl font-semibold text-foreground mb-3">
-                            Desktop Required
-                        </h1>
-                        <p className="text-sm text-muted-foreground leading-relaxed">
-                            This application works best on desktop or laptop devices. Please open it on a larger screen for the full experience.
-                        </p>
                     </div>
-                </div>
-            )}
+                </ResizablePanel>
 
-            {/* Draw.io Canvas */}
-            <div
-                className={`${isChatVisible ? 'w-2/3' : 'w-full'} h-full relative transition-all duration-300 ease-out`}
-            >
-                <div className="absolute inset-2 rounded-xl overflow-hidden shadow-soft-lg border border-border/30 bg-white">
-                    <DrawIoEmbed
-                        ref={drawioRef}
-                        onExport={handleDiagramExport}
-                        urlParameters={{
-                            spin: true,
-                            libraries: false,
-                            saveAndExit: false,
-                            noExitBtn: true,
-                        }}
-                    />
-                </div>
-            </div>
+                <ResizableHandle withHandle />
 
-            {/* Chat Panel */}
-            <div
-                className={`${isChatVisible ? 'w-1/3' : 'w-12'} h-full transition-all duration-300 ease-out`}
-            >
-                <div className="h-full py-2 pr-2">
-                    <ChatPanel
-                        isVisible={isChatVisible}
-                        onToggleVisibility={() => setIsChatVisible(!isChatVisible)}
-                    />
-                </div>
-            </div>
+                {/* Chat Panel */}
+                <ResizablePanel
+                    ref={chatPanelRef}
+                    defaultSize={isMobile ? 50 : 33}
+                    minSize={isMobile ? 20 : 15}
+                    maxSize={isMobile ? 80 : 50}
+                    collapsible={!isMobile}
+                    collapsedSize={isMobile ? 0 : 3}
+                    onCollapse={() => setIsChatVisible(false)}
+                    onExpand={() => setIsChatVisible(true)}
+                >
+                    <div className={`h-full ${isMobile ? "p-1" : "py-2 pr-2"}`}>
+                        <ChatPanel
+                            isVisible={isChatVisible}
+                            onToggleVisibility={toggleChatPanel}
+                            drawioUi={drawioUi}
+                            onToggleDrawioUi={() => {
+                                const newTheme = drawioUi === "min" ? "sketch" : "min";
+                                localStorage.setItem("drawio-theme", newTheme);
+                                setDrawioUi(newTheme);
+                            }}
+                            isMobile={isMobile}
+                        />
+                    </div>
+                </ResizablePanel>
+            </ResizablePanelGroup>
         </div>
     );
 }

components/button-with-tooltip.tsx

@@ -27,7 +27,7 @@ export function ButtonWithTooltip({
                 <TooltipTrigger asChild>
                     <Button {...buttonProps}>{children}</Button>
                 </TooltipTrigger>
-                <TooltipContent>{tooltipContent}</TooltipContent>
+                <TooltipContent className="max-w-xs text-wrap">{tooltipContent}</TooltipContent>
             </Tooltip>
         </TooltipProvider>
     );

components/chat-example-panel.tsx

@@ -90,7 +90,10 @@ export default function ExamplePanel({
                         icon={<Zap className="w-4 h-4 text-primary" />}
                         title="Animated Diagram"
                         description="Draw a transformer architecture with animated connectors"
-                        onClick={() => setInput("Give me a **animated connector** diagram of transformer's architecture")}
+                        onClick={() => {
+                            setInput("Give me a **animated connector** diagram of transformer's architecture")
+                            setFiles([])
+                        }}
                     />
 
                     <ExampleCard
@@ -111,7 +114,10 @@ export default function ExamplePanel({
                         icon={<Palette className="w-4 h-4 text-primary" />}
                         title="Creative Drawing"
                         description="Draw something fun and creative"
-                        onClick={() => setInput("Draw a cat for me")}
+                        onClick={() => {
+                            setInput("Draw a cat for me")
+                            setFiles([])
+                        }}
                     />
                 </div>
 

components/chat-input.tsx

@@ -5,6 +5,14 @@ import { Button } from "@/components/ui/button";
 import { Textarea } from "@/components/ui/textarea";
 import { ResetWarningModal } from "@/components/reset-warning-modal";
 import { SaveDialog } from "@/components/save-dialog";
+import {
+    Dialog,
+    DialogContent,
+    DialogDescription,
+    DialogFooter,
+    DialogHeader,
+    DialogTitle,
+} from "@/components/ui/dialog";
 import {
     Loader2,
     Send,
@@ -12,12 +20,80 @@ import {
     Image as ImageIcon,
     History,
     Download,
-    Paperclip,
+    PenTool,
+    LayoutGrid,
 } from "lucide-react";
+import { toast } from "sonner";
 import { ButtonWithTooltip } from "@/components/button-with-tooltip";
 import { FilePreviewList } from "./file-preview-list";
 import { useDiagram } from "@/contexts/diagram-context";
 import { HistoryDialog } from "@/components/history-dialog";
+import { ErrorToast } from "@/components/error-toast";
+
+const MAX_FILE_SIZE = 2 * 1024 * 1024; // 2MB
+const MAX_FILES = 5;
+
+function formatFileSize(bytes: number): string {
+    const mb = bytes / 1024 / 1024;
+    if (mb < 0.01) return `${(bytes / 1024).toFixed(0)}KB`;
+    return `${mb.toFixed(2)}MB`;
+}
+
+function showErrorToast(message: React.ReactNode) {
+    toast.custom(
+        (t) => <ErrorToast message={message} onDismiss={() => toast.dismiss(t)} />,
+        { duration: 5000 }
+    );
+}
+
+interface ValidationResult {
+    validFiles: File[];
+    errors: string[];
+}
+
+function validateFiles(newFiles: File[], existingCount: number): ValidationResult {
+    const errors: string[] = [];
+    const validFiles: File[] = [];
+
+    const availableSlots = MAX_FILES - existingCount;
+
+    if (availableSlots <= 0) {
+        errors.push(`Maximum ${MAX_FILES} files allowed`);
+        return { validFiles, errors };
+    }
+
+    for (const file of newFiles) {
+        if (validFiles.length >= availableSlots) {
+            errors.push(`Only ${availableSlots} more file(s) allowed`);
+            break;
+        }
+        if (file.size > MAX_FILE_SIZE) {
+            errors.push(`"${file.name}" is ${formatFileSize(file.size)} (exceeds 2MB)`);
+        } else {
+            validFiles.push(file);
+        }
+    }
+
+    return { validFiles, errors };
+}
+
+function showValidationErrors(errors: string[]) {
+    if (errors.length === 0) return;
+
+    if (errors.length === 1) {
+        showErrorToast(<span className="text-muted-foreground">{errors[0]}</span>);
+    } else {
+        showErrorToast(
+            <div className="flex flex-col gap-1">
+                <span className="font-medium">{errors.length} files rejected:</span>
+                <ul className="text-muted-foreground text-xs list-disc list-inside">
+                    {errors.slice(0, 3).map((err, i) => <li key={i}>{err}</li>)}
+                    {errors.length > 3 && <li>...and {errors.length - 3} more</li>}
+                </ul>
+            </div>
+        );
+    }
+}
 
 interface ChatInputProps {
     input: string;
@@ -29,6 +105,10 @@ interface ChatInputProps {
     onFileChange?: (files: File[]) => void;
     showHistory?: boolean;
     onToggleHistory?: (show: boolean) => void;
+    sessionId?: string;
+    error?: Error | null;
+    drawioUi?: "min" | "sketch";
+    onToggleDrawioUi?: () => void;
 }
 
 export function ChatInput({
@@ -41,6 +121,10 @@ export function ChatInput({
     onFileChange = () => {},
     showHistory = false,
     onToggleHistory = () => {},
+    sessionId,
+    error = null,
+    drawioUi = "min",
+    onToggleDrawioUi = () => {},
 }: ChatInputProps) {
     const { diagramHistory, saveDiagramToFile } = useDiagram();
     const textareaRef = useRef<HTMLTextAreaElement>(null);
@@ -48,12 +132,11 @@ export function ChatInput({
     const [isDragging, setIsDragging] = useState(false);
     const [showClearDialog, setShowClearDialog] = useState(false);
     const [showSaveDialog, setShowSaveDialog] = useState(false);
+    const [showThemeWarning, setShowThemeWarning] = useState(false);
 
-    const isDisabled = status === "streaming" || status === "submitted";
-
-    useEffect(() => {
-        console.log('[ChatInput] Status changed to:', status, '| Input disabled:', isDisabled);
-    }, [status, isDisabled]);
+    // Allow retry when there's an error (even if status is still "streaming" or "submitted")
+    const isDisabled =
+        (status === "streaming" || status === "submitted") && !error;
 
     const adjustTextareaHeight = useCallback(() => {
         const textarea = textareaRef.current;
@@ -86,23 +169,20 @@ export function ChatInput({
         );
 
         if (imageItems.length > 0) {
-            const imageFiles = await Promise.all(
-                imageItems.map(async (item) => {
+            const imageFiles = (await Promise.all(
+                imageItems.map(async (item, index) => {
                     const file = item.getAsFile();
                     if (!file) return null;
                     return new File(
                         [file],
-                        `pasted-image-${Date.now()}.${file.type.split("/")[1]}`,
-                        {
-                            type: file.type,
-                        }
+                        `pasted-image-${Date.now()}-${index}.${file.type.split("/")[1]}`,
+                        { type: file.type }
                     );
                 })
-            );
+            )).filter((f): f is File => f !== null);
 
-            const validFiles = imageFiles.filter(
-                (file): file is File => file !== null
-            );
+            const { validFiles, errors } = validateFiles(imageFiles, files.length);
+            showValidationErrors(errors);
             if (validFiles.length > 0) {
                 onFileChange([...files, ...validFiles]);
             }
@@ -111,7 +191,15 @@ export function ChatInput({
 
     const handleFileChange = (e: React.ChangeEvent<HTMLInputElement>) => {
         const newFiles = Array.from(e.target.files || []);
-        onFileChange([...files, ...newFiles]);
+        const { validFiles, errors } = validateFiles(newFiles, files.length);
+        showValidationErrors(errors);
+        if (validFiles.length > 0) {
+            onFileChange([...files, ...validFiles]);
+        }
+        // Reset input so same file can be selected again
+        if (fileInputRef.current) {
+            fileInputRef.current.value = "";
+        }
     };
 
     const handleRemoveFile = (fileToRemove: File) => {
@@ -145,13 +233,14 @@ export function ChatInput({
         if (isDisabled) return;
 
         const droppedFiles = e.dataTransfer.files;
-
         const imageFiles = Array.from(droppedFiles).filter((file) =>
             file.type.startsWith("image/")
         );
 
-        if (imageFiles.length > 0) {
-            onFileChange([...files, ...imageFiles]);
+        const { validFiles, errors } = validateFiles(imageFiles, files.length);
+        showValidationErrors(errors);
+        if (validFiles.length > 0) {
+            onFileChange([...files, ...validFiles]);
         }
     };
 
@@ -175,7 +264,10 @@ export function ChatInput({
             {/* File previews */}
             {files.length > 0 && (
                 <div className="mb-3">
-                    <FilePreviewList files={files} onRemoveFile={handleRemoveFile} />
+                    <FilePreviewList
+                        files={files}
+                        onRemoveFile={handleRemoveFile}
+                    />
                 </div>
             )}
 
@@ -218,6 +310,50 @@ export function ChatInput({
                             showHistory={showHistory}
                             onToggleHistory={onToggleHistory}
                         />
+
+                        <ButtonWithTooltip
+                            type="button"
+                            variant="ghost"
+                            size="sm"
+                            onClick={() => setShowThemeWarning(true)}
+                            tooltipContent={drawioUi === "min" ? "Switch to Sketch theme" : "Switch to Minimal theme"}
+                            className="h-8 w-8 p-0 text-muted-foreground hover:text-foreground"
+                        >
+                            {drawioUi === "min" ? (
+                                <PenTool className="h-4 w-4" />
+                            ) : (
+                                <LayoutGrid className="h-4 w-4" />
+                            )}
+                        </ButtonWithTooltip>
+
+                        <Dialog open={showThemeWarning} onOpenChange={setShowThemeWarning}>
+                            <DialogContent>
+                                <DialogHeader>
+                                    <DialogTitle>Switch Theme?</DialogTitle>
+                                    <DialogDescription>
+                                        Switching themes will reload the diagram editor and clear any unsaved changes.
+                                    </DialogDescription>
+                                </DialogHeader>
+                                <DialogFooter>
+                                    <Button
+                                        variant="outline"
+                                        onClick={() => setShowThemeWarning(false)}
+                                    >
+                                        Cancel
+                                    </Button>
+                                    <Button
+                                        variant="destructive"
+                                        onClick={() => {
+                                            onClearChat();
+                                            onToggleDrawioUi();
+                                            setShowThemeWarning(false);
+                                        }}
+                                    >
+                                        Switch Theme
+                                    </Button>
+                                </DialogFooter>
+                            </DialogContent>
+                        </Dialog>
                     </div>
 
                     {/* Right actions */}
@@ -249,8 +385,12 @@ export function ChatInput({
                         <SaveDialog
                             open={showSaveDialog}
                             onOpenChange={setShowSaveDialog}
-                            onSave={saveDiagramToFile}
-                            defaultFilename={`diagram-${new Date().toISOString().slice(0, 10)}`}
+                            onSave={(filename, format) =>
+                                saveDiagramToFile(filename, format, sessionId)
+                            }
+                            defaultFilename={`diagram-${new Date()
+                                .toISOString()
+                                .slice(0, 10)}`}
                         />
 
                         <ButtonWithTooltip
@@ -282,7 +422,9 @@ export function ChatInput({
                             disabled={isDisabled || !input.trim()}
                             size="sm"
                             className="h-8 px-4 rounded-xl font-medium shadow-sm"
-                            aria-label={isDisabled ? "Sending..." : "Send message"}
+                            aria-label={
+                                isDisabled ? "Sending..." : "Send message"
+                            }
                         >
                             {isDisabled ? (
                                 <Loader2 className="h-4 w-4 animate-spin" />
@@ -296,7 +438,6 @@ export function ChatInput({
                     </div>
                 </div>
             </div>
-
         </form>
     );
 }

components/chat-message-display.tsx

@@ -2,11 +2,12 @@
 
 import { useRef, useEffect, useState, useCallback } from "react";
 import Image from "next/image";
+import ReactMarkdown from "react-markdown";
 import { ScrollArea } from "@/components/ui/scroll-area";
 import ExamplePanel from "./chat-example-panel";
 import { UIMessage } from "ai";
 import { convertToLegalXml, replaceNodes, validateMxCellStructure } from "@/lib/utils";
-import { Copy, Check, X, ChevronDown, ChevronUp, Cpu, Minus, Plus } from "lucide-react";
+import { Copy, Check, X, ChevronDown, ChevronUp, Cpu, Minus, Plus, ThumbsUp, ThumbsDown, RotateCcw, Pencil } from "lucide-react";
 import { CodeBlock } from "./code-block";
 
 interface EditPair {
@@ -64,16 +65,20 @@ const getMessageTextContent = (message: UIMessage): string => {
 
 interface ChatMessageDisplayProps {
     messages: UIMessage[];
-    error?: Error | null;
     setInput: (input: string) => void;
     setFiles: (files: File[]) => void;
+    sessionId?: string;
+    onRegenerate?: (messageIndex: number) => void;
+    onEditMessage?: (messageIndex: number, newText: string) => void;
 }
 
 export function ChatMessageDisplay({
     messages,
-    error,
     setInput,
     setFiles,
+    sessionId,
+    onRegenerate,
+    onEditMessage,
 }: ChatMessageDisplayProps) {
     const { chartXML, loadDiagram: onDisplayChart } = useDiagram();
     const messagesEndRef = useRef<HTMLDivElement>(null);
@@ -84,6 +89,9 @@ export function ChatMessageDisplay({
     );
     const [copiedMessageId, setCopiedMessageId] = useState<string | null>(null);
     const [copyFailedMessageId, setCopyFailedMessageId] = useState<string | null>(null);
+    const [feedback, setFeedback] = useState<Record<string, "good" | "bad">>({});
+    const [editingMessageId, setEditingMessageId] = useState<string | null>(null);
+    const [editText, setEditText] = useState<string>("");
 
     const copyMessageToClipboard = async (messageId: string, text: string) => {
         try {
@@ -97,6 +105,34 @@ export function ChatMessageDisplay({
         }
     };
 
+    const submitFeedback = async (messageId: string, value: "good" | "bad") => {
+        // Toggle off if already selected
+        if (feedback[messageId] === value) {
+            setFeedback((prev) => {
+                const next = { ...prev };
+                delete next[messageId];
+                return next;
+            });
+            return;
+        }
+
+        setFeedback((prev) => ({ ...prev, [messageId]: value }));
+
+        try {
+            await fetch("/api/log-feedback", {
+                method: "POST",
+                headers: { "Content-Type": "application/json" },
+                body: JSON.stringify({
+                    messageId,
+                    feedback: value,
+                    sessionId,
+                }),
+            });
+        } catch (error) {
+            console.warn("Failed to log feedback:", error);
+        }
+    };
+
     const handleDisplayChart = useCallback(
         (xml: string) => {
             const currentXml = xml || "";
@@ -109,7 +145,7 @@ export function ChatMessageDisplay({
                     previousXML.current = convertedXml;
                     onDisplayChart(replacedXML);
                 } else {
-                    console.error("[ChatMessageDisplay] XML validation failed:", validationError);
+                    console.log("[ChatMessageDisplay] XML validation failed:", validationError);
                 }
             }
         },
@@ -246,72 +282,159 @@ export function ChatMessageDisplay({
     };
 
     return (
-        <ScrollArea className="h-full px-4 scrollbar-thin">
+        <ScrollArea className="h-full w-full scrollbar-thin">
             {messages.length === 0 ? (
                 <ExamplePanel setInput={setInput} setFiles={setFiles} />
             ) : (
-                <div className="py-4 space-y-4">
+                <div className="py-4 px-4 space-y-4">
                     {messages.map((message, messageIndex) => {
                         const userMessageText = message.role === "user" ? getMessageTextContent(message) : "";
+                        const isLastAssistantMessage = message.role === "assistant" && (
+                            messageIndex === messages.length - 1 ||
+                            messages.slice(messageIndex + 1).every(m => m.role !== "assistant")
+                        );
+                        const isLastUserMessage = message.role === "user" && (
+                            messageIndex === messages.length - 1 ||
+                            messages.slice(messageIndex + 1).every(m => m.role !== "user")
+                        );
+                        const isEditing = editingMessageId === message.id;
                         return (
                             <div
                                 key={message.id}
-                                className={`flex ${message.role === "user" ? "justify-end" : "justify-start"} animate-message-in`}
+                                className={`flex w-full ${message.role === "user" ? "justify-end" : "justify-start"} animate-message-in`}
                                 style={{ animationDelay: `${messageIndex * 50}ms` }}
                             >
-                                {message.role === "user" && userMessageText && (
-                                    <button
-                                        onClick={() => copyMessageToClipboard(message.id, userMessageText)}
-                                        className="p-1.5 rounded-lg text-muted-foreground/60 hover:text-muted-foreground hover:bg-muted transition-colors self-center mr-2"
-                                        title={copiedMessageId === message.id ? "Copied!" : copyFailedMessageId === message.id ? "Failed to copy" : "Copy message"}
-                                    >
-                                        {copiedMessageId === message.id ? (
-                                            <Check className="h-3.5 w-3.5 text-green-500" />
-                                        ) : copyFailedMessageId === message.id ? (
-                                            <X className="h-3.5 w-3.5 text-red-500" />
-                                        ) : (
-                                            <Copy className="h-3.5 w-3.5" />
+                                {message.role === "user" && userMessageText && !isEditing && (
+                                    <div className="flex items-center gap-1 self-center mr-2">
+                                        {/* Edit button - only on last user message */}
+                                        {onEditMessage && isLastUserMessage && (
+                                            <button
+                                                onClick={() => {
+                                                    setEditingMessageId(message.id);
+                                                    setEditText(userMessageText);
+                                                }}
+                                                className="p-1.5 rounded-lg text-muted-foreground/60 hover:text-muted-foreground hover:bg-muted transition-colors"
+                                                title="Edit message"
+                                            >
+                                                <Pencil className="h-3.5 w-3.5" />
+                                            </button>
                                         )}
-                                    </button>
-                                )}
-                                <div className="max-w-[85%]">
-                                    {/* Text content in bubble */}
-                                    {message.parts?.some((part: any) => part.type === "text" || part.type === "file") && (
-                                        <div
-                                            className={`px-4 py-3 text-sm leading-relaxed ${
-                                                message.role === "user"
-                                                    ? "bg-primary text-primary-foreground rounded-2xl rounded-br-md shadow-sm"
-                                                    : "bg-muted/60 text-foreground rounded-2xl rounded-bl-md"
-                                            }`}
+                                        <button
+                                            onClick={() => copyMessageToClipboard(message.id, userMessageText)}
+                                            className="p-1.5 rounded-lg text-muted-foreground/60 hover:text-muted-foreground hover:bg-muted transition-colors"
+                                            title={copiedMessageId === message.id ? "Copied!" : copyFailedMessageId === message.id ? "Failed to copy" : "Copy message"}
                                         >
-                                            {message.parts?.map((part: any, index: number) => {
-                                                switch (part.type) {
-                                                    case "text":
-                                                        return (
-                                                            <div key={index} className="whitespace-pre-wrap break-words">
-                                                                {part.text}
-                                                            </div>
-                                                        );
-                                                    case "file":
-                                                        return (
-                                                            <div key={index} className="mt-2">
-                                                                <Image
-                                                                    src={part.url}
-                                                                    width={200}
-                                                                    height={200}
-                                                                    alt={`Uploaded diagram or image for AI analysis`}
-                                                                    className="rounded-lg border border-white/20"
-                                                                    style={{
-                                                                        objectFit: "contain",
-                                                                    }}
-                                                                />
-                                                            </div>
-                                                        );
-                                                    default:
-                                                        return null;
-                                                }
-                                            })}
+                                            {copiedMessageId === message.id ? (
+                                                <Check className="h-3.5 w-3.5 text-green-500" />
+                                            ) : copyFailedMessageId === message.id ? (
+                                                <X className="h-3.5 w-3.5 text-red-500" />
+                                            ) : (
+                                                <Copy className="h-3.5 w-3.5" />
+                                            )}
+                                        </button>
+                                    </div>
+                                )}
+                                <div className="max-w-[85%] min-w-0">
+                                    {/* Edit mode for user messages */}
+                                    {isEditing && message.role === "user" ? (
+                                        <div className="flex flex-col gap-2">
+                                            <textarea
+                                                value={editText}
+                                                onChange={(e) => setEditText(e.target.value)}
+                                                className="w-full min-w-[300px] px-4 py-3 text-sm rounded-2xl border border-primary bg-background text-foreground resize-none focus:outline-none focus:ring-2 focus:ring-primary"
+                                                rows={Math.min(editText.split('\n').length + 1, 6)}
+                                                autoFocus
+                                                onKeyDown={(e) => {
+                                                    if (e.key === "Escape") {
+                                                        setEditingMessageId(null);
+                                                        setEditText("");
+                                                    } else if (e.key === "Enter" && (e.metaKey || e.ctrlKey)) {
+                                                        e.preventDefault();
+                                                        if (editText.trim() && onEditMessage) {
+                                                            onEditMessage(messageIndex, editText.trim());
+                                                            setEditingMessageId(null);
+                                                            setEditText("");
+                                                        }
+                                                    }
+                                                }}
+                                            />
+                                            <div className="flex justify-end gap-2">
+                                                <button
+                                                    onClick={() => {
+                                                        setEditingMessageId(null);
+                                                        setEditText("");
+                                                    }}
+                                                    className="px-3 py-1.5 text-xs rounded-lg bg-muted hover:bg-muted/80 transition-colors"
+                                                >
+                                                    Cancel
+                                                </button>
+                                                <button
+                                                    onClick={() => {
+                                                        if (editText.trim() && onEditMessage) {
+                                                            onEditMessage(messageIndex, editText.trim());
+                                                            setEditingMessageId(null);
+                                                            setEditText("");
+                                                        }
+                                                    }}
+                                                    disabled={!editText.trim()}
+                                                    className="px-3 py-1.5 text-xs rounded-lg bg-primary text-primary-foreground hover:bg-primary/90 disabled:opacity-50 transition-colors"
+                                                >
+                                                    Save & Submit
+                                                </button>
+                                            </div>
                                         </div>
+                                    ) : (
+                                        /* Text content in bubble */
+                                        message.parts?.some((part: any) => part.type === "text" || part.type === "file") && (
+                                            <div
+                                                className={`px-4 py-3 text-sm leading-relaxed ${
+                                                    message.role === "user"
+                                                        ? "bg-primary text-primary-foreground rounded-2xl rounded-br-md shadow-sm"
+                                                        : message.role === "system"
+                                                        ? "bg-destructive/10 text-destructive border border-destructive/20 rounded-2xl rounded-bl-md"
+                                                        : "bg-muted/60 text-foreground rounded-2xl rounded-bl-md"
+                                                } ${message.role === "user" && isLastUserMessage && onEditMessage ? "cursor-pointer hover:opacity-90 transition-opacity" : ""}`}
+                                                onClick={() => {
+                                                    if (message.role === "user" && isLastUserMessage && onEditMessage) {
+                                                        setEditingMessageId(message.id);
+                                                        setEditText(userMessageText);
+                                                    }
+                                                }}
+                                                title={message.role === "user" && isLastUserMessage && onEditMessage ? "Click to edit" : undefined}
+                                            >
+                                                {message.parts?.map((part: any, index: number) => {
+                                                    switch (part.type) {
+                                                        case "text":
+                                                            return (
+                                                                <div key={index} className={`prose prose-sm max-w-none break-words [&>*:first-child]:mt-0 [&>*:last-child]:mb-0 ${
+                                                                    message.role === "user"
+                                                                        ? "[&_*]:!text-primary-foreground prose-code:bg-white/20"
+                                                                        : "dark:prose-invert"
+                                                                }`}>
+                                                                    <ReactMarkdown>{part.text}</ReactMarkdown>
+                                                                </div>
+                                                            );
+                                                        case "file":
+                                                            return (
+                                                                <div key={index} className="mt-2">
+                                                                    <Image
+                                                                        src={part.url}
+                                                                        width={200}
+                                                                        height={200}
+                                                                        alt={`Uploaded diagram or image for AI analysis`}
+                                                                        className="rounded-lg border border-white/20"
+                                                                        style={{
+                                                                            objectFit: "contain",
+                                                                        }}
+                                                                    />
+                                                                </div>
+                                                            );
+                                                        default:
+                                                            return null;
+                                                    }
+                                                })}
+                                            </div>
+                                        )
                                     )}
                                     {/* Tool calls outside bubble */}
                                     {message.parts?.map((part: any) => {
@@ -320,17 +443,69 @@ export function ChatMessageDisplay({
                                         }
                                         return null;
                                     })}
+                                    {/* Action buttons for assistant messages */}
+                                    {message.role === "assistant" && (
+                                        <div className="flex items-center gap-1 mt-2">
+                                            {/* Copy button */}
+                                            <button
+                                                onClick={() => copyMessageToClipboard(message.id, getMessageTextContent(message))}
+                                                className={`p-1.5 rounded-lg transition-colors ${
+                                                    copiedMessageId === message.id
+                                                        ? "text-green-600 bg-green-100"
+                                                        : "text-muted-foreground/60 hover:text-foreground hover:bg-muted"
+                                                }`}
+                                                title={copiedMessageId === message.id ? "Copied!" : "Copy response"}
+                                            >
+                                                {copiedMessageId === message.id ? (
+                                                    <Check className="h-3.5 w-3.5" />
+                                                ) : (
+                                                    <Copy className="h-3.5 w-3.5" />
+                                                )}
+                                            </button>
+                                            {/* Regenerate button - only on last assistant message */}
+                                            {onRegenerate && isLastAssistantMessage && (
+                                                <button
+                                                    onClick={() => onRegenerate(messageIndex)}
+                                                    className="p-1.5 rounded-lg text-muted-foreground/60 hover:text-foreground hover:bg-muted transition-colors"
+                                                    title="Regenerate response"
+                                                >
+                                                    <RotateCcw className="h-3.5 w-3.5" />
+                                                </button>
+                                            )}
+                                            {/* Divider */}
+                                            <div className="w-px h-4 bg-border mx-1" />
+                                            {/* Thumbs up */}
+                                            <button
+                                                onClick={() => submitFeedback(message.id, "good")}
+                                                className={`p-1.5 rounded-lg transition-colors ${
+                                                    feedback[message.id] === "good"
+                                                        ? "text-green-600 bg-green-100"
+                                                        : "text-muted-foreground/60 hover:text-green-600 hover:bg-green-50"
+                                                }`}
+                                                title="Good response"
+                                            >
+                                                <ThumbsUp className="h-3.5 w-3.5" />
+                                            </button>
+                                            {/* Thumbs down */}
+                                            <button
+                                                onClick={() => submitFeedback(message.id, "bad")}
+                                                className={`p-1.5 rounded-lg transition-colors ${
+                                                    feedback[message.id] === "bad"
+                                                        ? "text-red-600 bg-red-100"
+                                                        : "text-muted-foreground/60 hover:text-red-600 hover:bg-red-50"
+                                                }`}
+                                                title="Bad response"
+                                            >
+                                                <ThumbsDown className="h-3.5 w-3.5" />
+                                            </button>
+                                        </div>
+                                    )}
                                 </div>
                             </div>
                         );
                     })}
                 </div>
             )}
-            {error && (
-                <div className="mx-4 mb-4 p-4 rounded-xl bg-red-50 border border-red-200 text-red-600 text-sm">
-                    <span className="font-medium">Error:</span> {error.message}
-                </div>
-            )}
             <div ref={messagesEndRef} />
         </ScrollArea>
     );

components/chat-panel.tsx

@@ -2,8 +2,14 @@
 
 import type React from "react";
 import { useRef, useEffect, useState } from "react";
+import { flushSync } from "react-dom";
 import { FaGithub } from "react-icons/fa";
-import { PanelRightClose, PanelRightOpen } from "lucide-react";
+import {
+    PanelRightClose,
+    PanelRightOpen,
+    Settings,
+    CheckCircle,
+} from "lucide-react";
 import Link from "next/link";
 import Image from "next/image";
 
@@ -14,15 +20,26 @@ import { ChatMessageDisplay } from "./chat-message-display";
 import { useDiagram } from "@/contexts/diagram-context";
 import { replaceNodes, formatXML, validateMxCellStructure } from "@/lib/utils";
 import { ButtonWithTooltip } from "@/components/button-with-tooltip";
+import { Toaster } from "sonner";
+import {
+    SettingsDialog,
+    STORAGE_ACCESS_CODE_KEY,
+} from "@/components/settings-dialog";
 
 interface ChatPanelProps {
     isVisible: boolean;
     onToggleVisibility: () => void;
+    drawioUi: "min" | "sketch";
+    onToggleDrawioUi: () => void;
+    isMobile?: boolean;
 }
 
 export default function ChatPanel({
     isVisible,
     onToggleVisibility,
+    drawioUi,
+    onToggleDrawioUi,
+    isMobile = false,
 }: ChatPanelProps) {
     const {
         loadDiagram: onDisplayChart,
@@ -59,10 +76,31 @@ export default function ChatPanel({
 
     const [files, setFiles] = useState<File[]>([]);
     const [showHistory, setShowHistory] = useState(false);
+    const [showSettingsDialog, setShowSettingsDialog] = useState(false);
+    const [accessCodeRequired, setAccessCodeRequired] = useState(false);
     const [input, setInput] = useState("");
 
+    // Check if access code is required on mount
+    useEffect(() => {
+        fetch("/api/config")
+            .then((res) => res.json())
+            .then((data) => setAccessCodeRequired(data.accessCodeRequired))
+            .catch(() => setAccessCodeRequired(false));
+    }, []);
+
     // Generate a unique session ID for Langfuse tracing
-    const [sessionId, setSessionId] = useState(() => `session-${Date.now()}-${Math.random().toString(36).slice(2, 9)}`);
+    const [sessionId, setSessionId] = useState(
+        () => `session-${Date.now()}-${Math.random().toString(36).slice(2, 9)}`
+    );
+
+    // Store XML snapshots for each user message (keyed by message index)
+    const xmlSnapshotsRef = useRef<Map<number, string>>(new Map());
+
+    // Ref to track latest chartXML for use in callbacks (avoids stale closure)
+    const chartXMLRef = useRef(chartXML);
+    useEffect(() => {
+        chartXMLRef.current = chartXML;
+    }, [chartXML]);
 
     const { messages, sendMessage, addToolResult, status, error, setMessages } =
         useChat({
@@ -95,8 +133,28 @@ export default function ChatPanel({
 
                     let currentXml = "";
                     try {
-                        // Fetch without saving to history - edit_diagram shouldn't create history entry
-                        currentXml = await onFetchChart(false);
+                        console.log("[edit_diagram] Starting...");
+                        // Use chartXML from ref directly - more reliable than export
+                        // especially on Vercel where DrawIO iframe may have latency issues
+                        // Using ref to avoid stale closure in callback
+                        const cachedXML = chartXMLRef.current;
+                        if (cachedXML) {
+                            currentXml = cachedXML;
+                            console.log(
+                                "[edit_diagram] Using cached chartXML, length:",
+                                currentXml.length
+                            );
+                        } else {
+                            // Fallback to export only if no cached XML
+                            console.log(
+                                "[edit_diagram] No cached XML, fetching from DrawIO..."
+                            );
+                            currentXml = await onFetchChart(false);
+                            console.log(
+                                "[edit_diagram] Got XML from export, length:",
+                                currentXml.length
+                            );
+                        }
 
                         const { replaceXMLParts } = await import("@/lib/utils");
                         const editedXml = replaceXMLParts(currentXml, edits);
@@ -108,8 +166,9 @@ export default function ChatPanel({
                             toolCallId: toolCall.toolCallId,
                             output: `Successfully applied ${edits.length} edit(s) to the diagram.`,
                         });
+                        console.log("[edit_diagram] Success");
                     } catch (error) {
-                        console.error("Edit diagram failed:", error);
+                        console.error("[edit_diagram] Failed:", error);
 
                         const errorMessage =
                             error instanceof Error
@@ -123,7 +182,7 @@ export default function ChatPanel({
 
 Current diagram XML:
 \`\`\`xml
-${currentXml}
+${currentXml || "No XML available"}
 \`\`\`
 
 Please retry with an adjusted search pattern or use display_diagram if retries are exhausted.`,
@@ -132,7 +191,27 @@ Please retry with an adjusted search pattern or use display_diagram if retries a
                 }
             },
             onError: (error) => {
-                console.error("Chat error:", error);
+                // Silence access code error in console since it's handled by UI
+                if (!error.message.includes("Invalid or missing access code")) {
+                    console.error("Chat error:", error);
+                }
+
+                // Add system message for error so it can be cleared
+                setMessages((currentMessages) => {
+                    const errorMessage = {
+                        id: `error-${Date.now()}`,
+                        role: "system" as const,
+                        content: error.message,
+                        parts: [{ type: "text" as const, text: error.message }],
+                    };
+                    return [...currentMessages, errorMessage];
+                });
+
+                if (error.message.includes("Invalid or missing access code")) {
+                    // Show settings button and open dialog to help user fix it
+                    setAccessCodeRequired(true);
+                    setShowSettingsDialog(true);
+                }
             },
         });
 
@@ -144,10 +223,6 @@ Please retry with an adjusted search pattern or use display_diagram if retries a
         }
     }, [messages]);
 
-    useEffect(() => {
-        console.log("[ChatPanel] Status changed to:", status);
-    }, [status]);
-
     const onFormSubmit = async (e: React.FormEvent<HTMLFormElement>) => {
         e.preventDefault();
         const isProcessing = status === "streaming" || status === "submitted";
@@ -156,6 +231,10 @@ Please retry with an adjusted search pattern or use display_diagram if retries a
                 let chartXml = await onFetchChart();
                 chartXml = formatXML(chartXml);
 
+                // Update ref directly to avoid race condition with React's async state update
+                // This ensures edit_diagram has the correct XML before AI responds
+                chartXMLRef.current = chartXml;
+
                 const parts: any[] = [{ type: "text", text: input }];
 
                 if (files.length > 0) {
@@ -175,6 +254,12 @@ Please retry with an adjusted search pattern or use display_diagram if retries a
                     }
                 }
 
+                // Save XML snapshot for this message (will be at index = current messages.length)
+                const messageIndex = messages.length;
+                xmlSnapshotsRef.current.set(messageIndex, chartXml);
+
+                const accessCode =
+                    localStorage.getItem(STORAGE_ACCESS_CODE_KEY) || "";
                 sendMessage(
                     { parts },
                     {
@@ -182,6 +267,9 @@ Please retry with an adjusted search pattern or use display_diagram if retries a
                             xml: chartXml,
                             sessionId,
                         },
+                        headers: {
+                            "x-access-code": accessCode,
+                        },
                     }
                 );
 
@@ -203,8 +291,129 @@ Please retry with an adjusted search pattern or use display_diagram if retries a
         setFiles(newFiles);
     };
 
-    // Collapsed view
-    if (!isVisible) {
+    const handleRegenerate = async (messageIndex: number) => {
+        const isProcessing = status === "streaming" || status === "submitted";
+        if (isProcessing) return;
+
+        // Find the user message before this assistant message
+        let userMessageIndex = messageIndex - 1;
+        while (
+            userMessageIndex >= 0 &&
+            messages[userMessageIndex].role !== "user"
+        ) {
+            userMessageIndex--;
+        }
+
+        if (userMessageIndex < 0) return;
+
+        const userMessage = messages[userMessageIndex];
+        const userParts = userMessage.parts;
+
+        // Get the text from the user message
+        const textPart = userParts?.find((p: any) => p.type === "text");
+        if (!textPart) return;
+
+        // Get the saved XML snapshot for this user message
+        const savedXml = xmlSnapshotsRef.current.get(userMessageIndex);
+        if (!savedXml) {
+            console.error(
+                "No saved XML snapshot for message index:",
+                userMessageIndex
+            );
+            return;
+        }
+
+        // Restore the diagram to the saved state
+        onDisplayChart(savedXml);
+
+        // Update ref directly to ensure edit_diagram has the correct XML
+        chartXMLRef.current = savedXml;
+
+        // Clean up snapshots for messages after the user message (they will be removed)
+        for (const key of xmlSnapshotsRef.current.keys()) {
+            if (key > userMessageIndex) {
+                xmlSnapshotsRef.current.delete(key);
+            }
+        }
+
+        // Remove the user message AND assistant message onwards (sendMessage will re-add the user message)
+        // Use flushSync to ensure state update is processed synchronously before sending
+        const newMessages = messages.slice(0, userMessageIndex);
+        flushSync(() => {
+            setMessages(newMessages);
+        });
+
+        // Now send the message after state is guaranteed to be updated
+        sendMessage(
+            { parts: userParts },
+            {
+                body: {
+                    xml: savedXml,
+                    sessionId,
+                },
+            }
+        );
+    };
+
+    const handleEditMessage = async (messageIndex: number, newText: string) => {
+        const isProcessing = status === "streaming" || status === "submitted";
+        if (isProcessing) return;
+
+        const message = messages[messageIndex];
+        if (!message || message.role !== "user") return;
+
+        // Get the saved XML snapshot for this user message
+        const savedXml = xmlSnapshotsRef.current.get(messageIndex);
+        if (!savedXml) {
+            console.error(
+                "No saved XML snapshot for message index:",
+                messageIndex
+            );
+            return;
+        }
+
+        // Restore the diagram to the saved state
+        onDisplayChart(savedXml);
+
+        // Update ref directly to ensure edit_diagram has the correct XML
+        chartXMLRef.current = savedXml;
+
+        // Clean up snapshots for messages after the user message (they will be removed)
+        for (const key of xmlSnapshotsRef.current.keys()) {
+            if (key > messageIndex) {
+                xmlSnapshotsRef.current.delete(key);
+            }
+        }
+
+        // Create new parts with updated text
+        const newParts = message.parts?.map((part: any) => {
+            if (part.type === "text") {
+                return { ...part, text: newText };
+            }
+            return part;
+        }) || [{ type: "text", text: newText }];
+
+        // Remove the user message AND assistant message onwards (sendMessage will re-add the user message)
+        // Use flushSync to ensure state update is processed synchronously before sending
+        const newMessages = messages.slice(0, messageIndex);
+        flushSync(() => {
+            setMessages(newMessages);
+        });
+
+        // Now send the edited message after state is guaranteed to be updated
+        sendMessage(
+            { parts: newParts },
+            {
+                body: {
+                    xml: savedXml,
+                    sessionId,
+                },
+            }
+        );
+    };
+
+    // Collapsed view (desktop only)
+    if (!isVisible && !isMobile) {
         return (
             <div className="h-full flex flex-col items-center pt-4 bg-card border border-border/30 rounded-xl">
                 <ButtonWithTooltip
@@ -231,29 +440,46 @@ Please retry with an adjusted search pattern or use display_diagram if retries a
 
     // Full view
     return (
-        <div className="h-full flex flex-col bg-card shadow-soft animate-slide-in-right rounded-xl border border-border/30">
+        <div className="h-full flex flex-col bg-card shadow-soft animate-slide-in-right rounded-xl border border-border/30 relative">
+            <Toaster
+                position="bottom-center"
+                richColors
+                style={{ position: "absolute" }}
+            />
             {/* Header */}
-            <header className="px-5 py-4 border-b border-border/50">
+            <header className={`${isMobile ? "px-3 py-2" : "px-5 py-4"} border-b border-border/50`}>
                 <div className="flex items-center justify-between">
-                    <div className="flex items-center gap-3">
+                    <div className="flex items-center gap-2">
                         <div className="flex items-center gap-2">
                             <Image
                                 src="/favicon.ico"
                                 alt="Next AI Drawio"
-                                width={28}
-                                height={28}
+                                width={isMobile ? 24 : 28}
+                                height={isMobile ? 24 : 28}
                                 className="rounded"
                             />
-                            <h1 className="text-base font-semibold tracking-tight whitespace-nowrap">
+                            <h1 className={`${isMobile ? "text-sm" : "text-base"} font-semibold tracking-tight whitespace-nowrap`}>
                                 Next AI Drawio
                             </h1>
                         </div>
-                        <Link
-                            href="/about"
-                            className="text-sm text-muted-foreground hover:text-foreground transition-colors ml-2"
-                        >
-                            About
-                        </Link>
+                        {!isMobile && (
+                            <Link
+                                href="/about"
+                                className="text-sm text-muted-foreground hover:text-foreground transition-colors ml-2"
+                            >
+                                About
+                            </Link>
+                        )}
+                        {!isMobile && (
+                            <ButtonWithTooltip
+                                tooltipContent="Recent generation failures were caused by our AI provider's infrastructure issue, not the app code. After extensive debugging, I've switched providers and observed 6 hours of stability. If issues persist, please report on GitHub."
+                                variant="ghost"
+                                size="icon"
+                                className="h-6 w-6 text-green-500 hover:text-green-600"
+                            >
+                                <CheckCircle className="h-4 w-4" />
+                            </ButtonWithTooltip>
+                        )}
                     </div>
                     <div className="flex items-center gap-1">
                         <a
@@ -262,33 +488,48 @@ Please retry with an adjusted search pattern or use display_diagram if retries a
                             rel="noopener noreferrer"
                             className="p-2 rounded-lg text-muted-foreground hover:text-foreground hover:bg-accent transition-colors"
                         >
-                            <FaGithub className="w-5 h-5" />
+                            <FaGithub className={`${isMobile ? "w-4 h-4" : "w-5 h-5"}`} />
                         </a>
-                        <ButtonWithTooltip
-                            tooltipContent="Hide chat panel (Ctrl+B)"
-                            variant="ghost"
-                            size="icon"
-                            onClick={onToggleVisibility}
-                            className="hover:bg-accent"
-                        >
-                            <PanelRightClose className="h-5 w-5 text-muted-foreground" />
-                        </ButtonWithTooltip>
+                        {accessCodeRequired && (
+                            <ButtonWithTooltip
+                                tooltipContent="Settings"
+                                variant="ghost"
+                                size="icon"
+                                onClick={() => setShowSettingsDialog(true)}
+                                className="hover:bg-accent"
+                            >
+                                <Settings className={`${isMobile ? "h-4 w-4" : "h-5 w-5"} text-muted-foreground`} />
+                            </ButtonWithTooltip>
+                        )}
+                        {!isMobile && (
+                            <ButtonWithTooltip
+                                tooltipContent="Hide chat panel (Ctrl+B)"
+                                variant="ghost"
+                                size="icon"
+                                onClick={onToggleVisibility}
+                                className="hover:bg-accent"
+                            >
+                                <PanelRightClose className="h-5 w-5 text-muted-foreground" />
+                            </ButtonWithTooltip>
+                        )}
                     </div>
                 </div>
             </header>
 
             {/* Messages */}
-            <main className="flex-1 overflow-hidden">
+            <main className="flex-1 w-full overflow-hidden">
                 <ChatMessageDisplay
                     messages={messages}
-                    error={error}
                     setInput={setInput}
                     setFiles={handleFileChange}
+                    sessionId={sessionId}
+                    onRegenerate={handleRegenerate}
+                    onEditMessage={handleEditMessage}
                 />
             </main>
 
             {/* Input */}
-            <footer className="p-4 border-t border-border/50 bg-card/50">
+            <footer className={`${isMobile ? "p-2" : "p-4"} border-t border-border/50 bg-card/50`}>
                 <ChatInput
                     input={input}
                     status={status}
@@ -297,14 +538,28 @@ Please retry with an adjusted search pattern or use display_diagram if retries a
                     onClearChat={() => {
                         setMessages([]);
                         clearDiagram();
-                        setSessionId(`session-${Date.now()}-${Math.random().toString(36).slice(2, 9)}`);
+                        setSessionId(
+                            `session-${Date.now()}-${Math.random()
+                                .toString(36)
+                                .slice(2, 9)}`
+                        );
+                        xmlSnapshotsRef.current.clear();
                     }}
                     files={files}
                     onFileChange={handleFileChange}
                     showHistory={showHistory}
                     onToggleHistory={setShowHistory}
+                    sessionId={sessionId}
+                    error={error}
+                    drawioUi={drawioUi}
+                    onToggleDrawioUi={onToggleDrawioUi}
                 />
             </footer>
+
+            <SettingsDialog
+                open={showSettingsDialog}
+                onOpenChange={setShowSettingsDialog}
+            />
         </div>
     );
 }

components/error-toast.tsx

@@ -0,0 +1,39 @@
+"use client";
+
+import React from "react";
+
+interface ErrorToastProps {
+    message: React.ReactNode;
+    onDismiss: () => void;
+}
+
+export function ErrorToast({ message, onDismiss }: ErrorToastProps) {
+    const handleKeyDown = (e: React.KeyboardEvent) => {
+        if (e.key === "Enter" || e.key === " " || e.key === "Escape") {
+            e.preventDefault();
+            onDismiss();
+        }
+    };
+
+    return (
+        <div
+            role="alert"
+            aria-live="polite"
+            tabIndex={0}
+            onClick={onDismiss}
+            onKeyDown={handleKeyDown}
+            className="flex items-center gap-3 bg-card border border-border/50 px-4 py-3 rounded-xl shadow-sm cursor-pointer hover:bg-muted/50 focus:outline-none focus:ring-2 focus:ring-primary/50 transition-colors"
+        >
+            <div className="flex items-center justify-center w-8 h-8 rounded-full bg-destructive/10 flex-shrink-0">
+                <svg className="w-4 h-4 text-destructive" viewBox="0 0 20 20" fill="currentColor" aria-hidden="true">
+                    <path
+                        fillRule="evenodd"
+                        d="M4.293 4.293a1 1 0 011.414 0L10 8.586l4.293-4.293a1 1 0 111.414 1.414L11.414 10l4.293 4.293a1 1 0 01-1.414 1.414L10 11.414l-4.293 4.293a1 1 0 01-1.414-1.414L8.586 10 4.293 5.707a1 1 0 010-1.414z"
+                        clipRule="evenodd"
+                    />
+                </svg>
+            </div>
+            <span className="text-sm text-foreground">{message}</span>
+        </div>
+    );
+}

components/save-dialog.tsx

@@ -10,11 +10,26 @@ import {
     DialogTitle,
     DialogFooter,
 } from "@/components/ui/dialog";
+import {
+    Select,
+    SelectContent,
+    SelectItem,
+    SelectTrigger,
+    SelectValue,
+} from "@/components/ui/select";
+
+export type ExportFormat = "drawio" | "png" | "svg";
+
+const FORMAT_OPTIONS: { value: ExportFormat; label: string; extension: string }[] = [
+    { value: "drawio", label: "Draw.io XML", extension: ".drawio" },
+    { value: "png", label: "PNG Image", extension: ".png" },
+    { value: "svg", label: "SVG Image", extension: ".svg" },
+];
 
 interface SaveDialogProps {
     open: boolean;
     onOpenChange: (open: boolean) => void;
-    onSave: (filename: string) => void;
+    onSave: (filename: string, format: ExportFormat) => void;
     defaultFilename: string;
 }
 
@@ -25,6 +40,7 @@ export function SaveDialog({
     defaultFilename,
 }: SaveDialogProps) {
     const [filename, setFilename] = useState(defaultFilename);
+    const [format, setFormat] = useState<ExportFormat>("drawio");
 
     useEffect(() => {
         if (open) {
@@ -34,7 +50,7 @@ export function SaveDialog({
 
     const handleSave = () => {
         const finalFilename = filename.trim() || defaultFilename;
-        onSave(finalFilename);
+        onSave(finalFilename, format);
         onOpenChange(false);
     };
 
@@ -45,27 +61,46 @@ export function SaveDialog({
         }
     };
 
+    const currentFormat = FORMAT_OPTIONS.find((f) => f.value === format);
+
     return (
         <Dialog open={open} onOpenChange={onOpenChange}>
             <DialogContent className="sm:max-w-md">
                 <DialogHeader>
                     <DialogTitle>Save Diagram</DialogTitle>
                 </DialogHeader>
-                <div className="space-y-2">
-                    <label className="text-sm font-medium">Filename</label>
-                    <div className="flex items-stretch">
-                        <Input
-                            value={filename}
-                            onChange={(e) => setFilename(e.target.value)}
-                            onKeyDown={handleKeyDown}
-                            placeholder="Enter filename"
-                            autoFocus
-                            onFocus={(e) => e.target.select()}
-                            className="rounded-r-none border-r-0 focus-visible:z-10"
-                        />
-                        <span className="inline-flex items-center px-3 rounded-r-md border border-l-0 border-input bg-muted text-sm text-muted-foreground font-mono">
-                            .drawio
-                        </span>
+                <div className="space-y-4">
+                    <div className="space-y-2">
+                        <label className="text-sm font-medium">Format</label>
+                        <Select value={format} onValueChange={(v) => setFormat(v as ExportFormat)}>
+                            <SelectTrigger>
+                                <SelectValue />
+                            </SelectTrigger>
+                            <SelectContent>
+                                {FORMAT_OPTIONS.map((opt) => (
+                                    <SelectItem key={opt.value} value={opt.value}>
+                                        {opt.label}
+                                    </SelectItem>
+                                ))}
+                            </SelectContent>
+                        </Select>
+                    </div>
+                    <div className="space-y-2">
+                        <label className="text-sm font-medium">Filename</label>
+                        <div className="flex items-stretch">
+                            <Input
+                                value={filename}
+                                onChange={(e) => setFilename(e.target.value)}
+                                onKeyDown={handleKeyDown}
+                                placeholder="Enter filename"
+                                autoFocus
+                                onFocus={(e) => e.target.select()}
+                                className="rounded-r-none border-r-0 focus-visible:z-10"
+                            />
+                            <span className="inline-flex items-center px-3 rounded-r-md border border-l-0 border-input bg-muted text-sm text-muted-foreground font-mono">
+                                {currentFormat?.extension || ".drawio"}
+                            </span>
+                        </div>
                     </div>
                 </div>
                 <DialogFooter>

components/settings-dialog.tsx

@@ -0,0 +1,83 @@
+"use client";
+
+import { useState, useEffect } from "react";
+import { Button } from "@/components/ui/button";
+import { Input } from "@/components/ui/input";
+import {
+    Dialog,
+    DialogContent,
+    DialogHeader,
+    DialogTitle,
+    DialogFooter,
+    DialogDescription,
+} from "@/components/ui/dialog";
+
+interface SettingsDialogProps {
+    open: boolean;
+    onOpenChange: (open: boolean) => void;
+}
+
+export const STORAGE_ACCESS_CODE_KEY = "next-ai-draw-io-access-code";
+
+export function SettingsDialog({
+    open,
+    onOpenChange,
+}: SettingsDialogProps) {
+    const [accessCode, setAccessCode] = useState("");
+
+    useEffect(() => {
+        if (open) {
+            const storedCode = localStorage.getItem(STORAGE_ACCESS_CODE_KEY) || "";
+            setAccessCode(storedCode);
+        }
+    }, [open]);
+
+    const handleSave = () => {
+        localStorage.setItem(STORAGE_ACCESS_CODE_KEY, accessCode.trim());
+        onOpenChange(false);
+    };
+
+    const handleKeyDown = (e: React.KeyboardEvent) => {
+        if (e.key === "Enter") {
+            e.preventDefault();
+            handleSave();
+        }
+    };
+
+    return (
+        <Dialog open={open} onOpenChange={onOpenChange}>
+            <DialogContent className="sm:max-w-md">
+                <DialogHeader>
+                    <DialogTitle>Settings</DialogTitle>
+                    <DialogDescription>
+                        Configure your access settings.
+                    </DialogDescription>
+                </DialogHeader>
+                <div className="space-y-4 py-2">
+                    <div className="space-y-2">
+                        <label className="text-sm font-medium leading-none peer-disabled:cursor-not-allowed peer-disabled:opacity-70">
+                            Access Code
+                        </label>
+                        <Input
+                            type="password"
+                            value={accessCode}
+                            onChange={(e) => setAccessCode(e.target.value)}
+                            onKeyDown={handleKeyDown}
+                            placeholder="Enter access code"
+                            autoComplete="off"
+                        />
+                        <p className="text-[0.8rem] text-muted-foreground">
+                            Required if the server has enabled access control.
+                        </p>
+                    </div>
+                </div>
+                <DialogFooter>
+                    <Button variant="outline" onClick={() => onOpenChange(false)}>
+                        Cancel
+                    </Button>
+                    <Button onClick={handleSave}>Save</Button>
+                </DialogFooter>
+            </DialogContent>
+        </Dialog>
+    );
+}

components/ui/button.tsx

@@ -10,7 +10,7 @@ const buttonVariants = cva(
     variants: {
       variant: {
         default:
-          "bg-primary text-primary-foreground shadow-xs hover:bg-primary/90",
+          "bg-primary text-primary-foreground shadow-xs hover:brightness-75",
         destructive:
           "bg-destructive text-white shadow-xs hover:bg-destructive/90 focus-visible:ring-destructive/20 dark:focus-visible:ring-destructive/40 dark:bg-destructive/60",
         outline:

components/ui/resizable.tsx

@@ -0,0 +1,56 @@
+"use client"
+
+import * as React from "react"
+import { GripVerticalIcon } from "lucide-react"
+import * as ResizablePrimitive from "react-resizable-panels"
+
+import { cn } from "@/lib/utils"
+
+function ResizablePanelGroup({
+  className,
+  ...props
+}: React.ComponentProps<typeof ResizablePrimitive.PanelGroup>) {
+  return (
+    <ResizablePrimitive.PanelGroup
+      data-slot="resizable-panel-group"
+      className={cn(
+        "flex h-full w-full data-[panel-group-direction=vertical]:flex-col",
+        className
+      )}
+      {...props}
+    />
+  )
+}
+
+function ResizablePanel({
+  ...props
+}: React.ComponentProps<typeof ResizablePrimitive.Panel>) {
+  return <ResizablePrimitive.Panel data-slot="resizable-panel" {...props} />
+}
+
+function ResizableHandle({
+  withHandle,
+  className,
+  ...props
+}: React.ComponentProps<typeof ResizablePrimitive.PanelResizeHandle> & {
+  withHandle?: boolean
+}) {
+  return (
+    <ResizablePrimitive.PanelResizeHandle
+      data-slot="resizable-handle"
+      className={cn(
+        "bg-border focus-visible:ring-ring relative flex w-px items-center justify-center after:absolute after:inset-y-0 after:left-1/2 after:w-1 after:-translate-x-1/2 focus-visible:ring-1 focus-visible:ring-offset-1 focus-visible:outline-hidden data-[panel-group-direction=vertical]:h-px data-[panel-group-direction=vertical]:w-full data-[panel-group-direction=vertical]:after:left-0 data-[panel-group-direction=vertical]:after:h-1 data-[panel-group-direction=vertical]:after:w-full data-[panel-group-direction=vertical]:after:translate-x-0 data-[panel-group-direction=vertical]:after:-translate-y-1/2 [&[data-panel-group-direction=vertical]>div]:rotate-90",
+        className
+      )}
+      {...props}
+    >
+      {withHandle && (
+        <div className="bg-border z-10 flex h-4 w-3 items-center justify-center rounded-xs border">
+          <GripVerticalIcon className="size-2.5" />
+        </div>
+      )}
+    </ResizablePrimitive.PanelResizeHandle>
+  )
+}
+
+export { ResizablePanelGroup, ResizablePanel, ResizableHandle }

components/ui/scroll-area.tsx

@@ -18,7 +18,7 @@ function ScrollArea({
     >
       <ScrollAreaPrimitive.Viewport
         data-slot="scroll-area-viewport"
-        className="ring-ring/10 dark:ring-ring/20 dark:outline-ring/40 outline-ring/50 size-full rounded-[inherit] transition-[color,box-shadow] focus-visible:ring-4 focus-visible:outline-1"
+        className="ring-ring/10 dark:ring-ring/20 dark:outline-ring/40 outline-ring/50 size-full rounded-[inherit] transition-[color,box-shadow] focus-visible:ring-4 focus-visible:outline-1 !overflow-x-hidden"
       >
         {children}
       </ScrollAreaPrimitive.Viewport>

components/ui/select.tsx

@@ -0,0 +1,187 @@
+"use client"
+
+import * as React from "react"
+import * as SelectPrimitive from "@radix-ui/react-select"
+import { CheckIcon, ChevronDownIcon, ChevronUpIcon } from "lucide-react"
+
+import { cn } from "@/lib/utils"
+
+function Select({
+  ...props
+}: React.ComponentProps<typeof SelectPrimitive.Root>) {
+  return <SelectPrimitive.Root data-slot="select" {...props} />
+}
+
+function SelectGroup({
+  ...props
+}: React.ComponentProps<typeof SelectPrimitive.Group>) {
+  return <SelectPrimitive.Group data-slot="select-group" {...props} />
+}
+
+function SelectValue({
+  ...props
+}: React.ComponentProps<typeof SelectPrimitive.Value>) {
+  return <SelectPrimitive.Value data-slot="select-value" {...props} />
+}
+
+function SelectTrigger({
+  className,
+  size = "default",
+  children,
+  ...props
+}: React.ComponentProps<typeof SelectPrimitive.Trigger> & {
+  size?: "sm" | "default"
+}) {
+  return (
+    <SelectPrimitive.Trigger
+      data-slot="select-trigger"
+      data-size={size}
+      className={cn(
+        "border-input data-[placeholder]:text-muted-foreground [&_svg:not([class*='text-'])]:text-muted-foreground focus-visible:border-ring focus-visible:ring-ring/50 aria-invalid:ring-destructive/20 dark:aria-invalid:ring-destructive/40 aria-invalid:border-destructive dark:bg-input/30 dark:hover:bg-input/50 flex w-fit items-center justify-between gap-2 rounded-md border bg-transparent px-3 py-2 text-sm whitespace-nowrap shadow-xs transition-[color,box-shadow] outline-none focus-visible:ring-[3px] disabled:cursor-not-allowed disabled:opacity-50 data-[size=default]:h-9 data-[size=sm]:h-8 *:data-[slot=select-value]:line-clamp-1 *:data-[slot=select-value]:flex *:data-[slot=select-value]:items-center *:data-[slot=select-value]:gap-2 [&_svg]:pointer-events-none [&_svg]:shrink-0 [&_svg:not([class*='size-'])]:size-4",
+        className
+      )}
+      {...props}
+    >
+      {children}
+      <SelectPrimitive.Icon asChild>
+        <ChevronDownIcon className="size-4 opacity-50" />
+      </SelectPrimitive.Icon>
+    </SelectPrimitive.Trigger>
+  )
+}
+
+function SelectContent({
+  className,
+  children,
+  position = "popper",
+  align = "center",
+  ...props
+}: React.ComponentProps<typeof SelectPrimitive.Content>) {
+  return (
+    <SelectPrimitive.Portal>
+      <SelectPrimitive.Content
+        data-slot="select-content"
+        className={cn(
+          "bg-popover text-popover-foreground data-[state=open]:animate-in data-[state=closed]:animate-out data-[state=closed]:fade-out-0 data-[state=open]:fade-in-0 data-[state=closed]:zoom-out-95 data-[state=open]:zoom-in-95 data-[side=bottom]:slide-in-from-top-2 data-[side=left]:slide-in-from-right-2 data-[side=right]:slide-in-from-left-2 data-[side=top]:slide-in-from-bottom-2 relative z-50 max-h-(--radix-select-content-available-height) min-w-[8rem] origin-(--radix-select-content-transform-origin) overflow-x-hidden overflow-y-auto rounded-md border shadow-md",
+          position === "popper" &&
+            "data-[side=bottom]:translate-y-1 data-[side=left]:-translate-x-1 data-[side=right]:translate-x-1 data-[side=top]:-translate-y-1",
+          className
+        )}
+        position={position}
+        align={align}
+        {...props}
+      >
+        <SelectScrollUpButton />
+        <SelectPrimitive.Viewport
+          className={cn(
+            "p-1",
+            position === "popper" &&
+              "h-[var(--radix-select-trigger-height)] w-full min-w-[var(--radix-select-trigger-width)] scroll-my-1"
+          )}
+        >
+          {children}
+        </SelectPrimitive.Viewport>
+        <SelectScrollDownButton />
+      </SelectPrimitive.Content>
+    </SelectPrimitive.Portal>
+  )
+}
+
+function SelectLabel({
+  className,
+  ...props
+}: React.ComponentProps<typeof SelectPrimitive.Label>) {
+  return (
+    <SelectPrimitive.Label
+      data-slot="select-label"
+      className={cn("text-muted-foreground px-2 py-1.5 text-xs", className)}
+      {...props}
+    />
+  )
+}
+
+function SelectItem({
+  className,
+  children,
+  ...props
+}: React.ComponentProps<typeof SelectPrimitive.Item>) {
+  return (
+    <SelectPrimitive.Item
+      data-slot="select-item"
+      className={cn(
+        "focus:bg-accent focus:text-accent-foreground [&_svg:not([class*='text-'])]:text-muted-foreground relative flex w-full cursor-default items-center gap-2 rounded-sm py-1.5 pr-8 pl-2 text-sm outline-hidden select-none data-[disabled]:pointer-events-none data-[disabled]:opacity-50 [&_svg]:pointer-events-none [&_svg]:shrink-0 [&_svg:not([class*='size-'])]:size-4 *:[span]:last:flex *:[span]:last:items-center *:[span]:last:gap-2",
+        className
+      )}
+      {...props}
+    >
+      <span className="absolute right-2 flex size-3.5 items-center justify-center">
+        <SelectPrimitive.ItemIndicator>
+          <CheckIcon className="size-4" />
+        </SelectPrimitive.ItemIndicator>
+      </span>
+      <SelectPrimitive.ItemText>{children}</SelectPrimitive.ItemText>
+    </SelectPrimitive.Item>
+  )
+}
+
+function SelectSeparator({
+  className,
+  ...props
+}: React.ComponentProps<typeof SelectPrimitive.Separator>) {
+  return (
+    <SelectPrimitive.Separator
+      data-slot="select-separator"
+      className={cn("bg-border pointer-events-none -mx-1 my-1 h-px", className)}
+      {...props}
+    />
+  )
+}
+
+function SelectScrollUpButton({
+  className,
+  ...props
+}: React.ComponentProps<typeof SelectPrimitive.ScrollUpButton>) {
+  return (
+    <SelectPrimitive.ScrollUpButton
+      data-slot="select-scroll-up-button"
+      className={cn(
+        "flex cursor-default items-center justify-center py-1",
+        className
+      )}
+      {...props}
+    >
+      <ChevronUpIcon className="size-4" />
+    </SelectPrimitive.ScrollUpButton>
+  )
+}
+
+function SelectScrollDownButton({
+  className,
+  ...props
+}: React.ComponentProps<typeof SelectPrimitive.ScrollDownButton>) {
+  return (
+    <SelectPrimitive.ScrollDownButton
+      data-slot="select-scroll-down-button"
+      className={cn(
+        "flex cursor-default items-center justify-center py-1",
+        className
+      )}
+      {...props}
+    >
+      <ChevronDownIcon className="size-4" />
+    </SelectPrimitive.ScrollDownButton>
+  )
+}
+
+export {
+  Select,
+  SelectContent,
+  SelectGroup,
+  SelectItem,
+  SelectLabel,
+  SelectScrollDownButton,
+  SelectScrollUpButton,
+  SelectSeparator,
+  SelectTrigger,
+  SelectValue,
+}

contexts/diagram-context.tsx

@@ -3,6 +3,7 @@
 import React, { createContext, useContext, useRef, useState } from "react";
 import type { DrawIoEmbedRef } from "react-drawio";
 import { extractDiagramXML } from "../lib/utils";
+import type { ExportFormat } from "@/components/save-dialog";
 
 interface DiagramContextType {
     chartXML: string;
@@ -15,7 +16,7 @@ interface DiagramContextType {
     drawioRef: React.Ref<DrawIoEmbedRef | null>;
     handleDiagramExport: (data: any) => void;
     clearDiagram: () => void;
-    saveDiagramToFile: (filename: string) => void;
+    saveDiagramToFile: (filename: string, format: ExportFormat, sessionId?: string) => void;
 }
 
 const DiagramContext = createContext<DiagramContextType | undefined>(undefined);
@@ -30,8 +31,11 @@ export function DiagramProvider({ children }: { children: React.ReactNode }) {
     const resolverRef = useRef<((value: string) => void) | null>(null);
     // Track if we're expecting an export for history (user-initiated)
     const expectHistoryExportRef = useRef<boolean>(false);
-    // Track if we're expecting an export for file save
-    const saveResolverRef = useRef<((xml: string) => void) | null>(null);
+    // Track if we're expecting an export for file save (stores raw export data)
+    const saveResolverRef = useRef<{
+        resolver: ((data: string) => void) | null;
+        format: ExportFormat | null;
+    }>({ resolver: null, format: null });
 
     const handleExport = () => {
         if (drawioRef.current) {
@@ -61,6 +65,18 @@ export function DiagramProvider({ children }: { children: React.ReactNode }) {
     };
 
     const handleDiagramExport = (data: any) => {
+        // Handle save to file if requested (process raw data before extraction)
+        if (saveResolverRef.current.resolver) {
+            const format = saveResolverRef.current.format;
+            saveResolverRef.current.resolver(data.data);
+            saveResolverRef.current = { resolver: null, format: null };
+            // For non-xmlsvg formats, skip XML extraction as it will fail
+            // Only drawio (which uses xmlsvg internally) has the content attribute
+            if (format === "png" || format === "svg") {
+                return;
+            }
+        }
+
         const extractedXML = extractDiagramXML(data.data);
         setChartXML(extractedXML);
         setLatestSvg(data.data);
@@ -81,12 +97,6 @@ export function DiagramProvider({ children }: { children: React.ReactNode }) {
             resolverRef.current(extractedXML);
             resolverRef.current = null;
         }
-
-        // Handle save to file if requested
-        if (saveResolverRef.current) {
-            saveResolverRef.current(extractedXML);
-            saveResolverRef.current = null;
-        }
     };
 
     const clearDiagram = () => {
@@ -97,33 +107,87 @@ export function DiagramProvider({ children }: { children: React.ReactNode }) {
         setDiagramHistory([]);
     };
 
-    const saveDiagramToFile = (filename: string) => {
+    const saveDiagramToFile = (filename: string, format: ExportFormat, sessionId?: string) => {
         if (!drawioRef.current) {
             console.warn("Draw.io editor not ready");
             return;
         }
 
-        // Export diagram and save when export completes
-        drawioRef.current.exportDiagram({ format: "xmlsvg" });
-        saveResolverRef.current = (xml: string) => {
-            // Wrap in proper .drawio format
-            let fileContent = xml;
-            if (!xml.includes("<mxfile")) {
-                fileContent = `<mxfile><diagram name="Page-1" id="page-1">${xml}</diagram></mxfile>`;
-            }
+        // Map format to draw.io export format
+        const drawioFormat = format === "drawio" ? "xmlsvg" : format;
 
-            const blob = new Blob([fileContent], { type: "application/xml" });
-            const url = URL.createObjectURL(blob);
-            const a = document.createElement("a");
-            a.href = url;
-            // Add .drawio extension if not present
-            a.download = filename.endsWith(".drawio") ? filename : `${filename}.drawio`;
-            document.body.appendChild(a);
-            a.click();
-            document.body.removeChild(a);
-            // Delay URL revocation to ensure download completes
-            setTimeout(() => URL.revokeObjectURL(url), 100);
+        // Set up the resolver before triggering export
+        saveResolverRef.current = {
+            resolver: (exportData: string) => {
+                let fileContent: string | Blob;
+                let mimeType: string;
+                let extension: string;
+
+                if (format === "drawio") {
+                    // Extract XML from SVG for .drawio format
+                    const xml = extractDiagramXML(exportData);
+                    let xmlContent = xml;
+                    if (!xml.includes("<mxfile")) {
+                        xmlContent = `<mxfile><diagram name="Page-1" id="page-1">${xml}</diagram></mxfile>`;
+                    }
+                    fileContent = xmlContent;
+                    mimeType = "application/xml";
+                    extension = ".drawio";
+                } else if (format === "png") {
+                    // PNG data comes as base64 data URL
+                    fileContent = exportData;
+                    mimeType = "image/png";
+                    extension = ".png";
+                } else {
+                    // SVG format
+                    fileContent = exportData;
+                    mimeType = "image/svg+xml";
+                    extension = ".svg";
+                }
+
+                // Log save event to Langfuse (flags the trace)
+                logSaveToLangfuse(filename, format, sessionId);
+
+                // Handle download
+                let url: string;
+                if (typeof fileContent === "string" && fileContent.startsWith("data:")) {
+                    // Already a data URL (PNG)
+                    url = fileContent;
+                } else {
+                    const blob = new Blob([fileContent], { type: mimeType });
+                    url = URL.createObjectURL(blob);
+                }
+
+                const a = document.createElement("a");
+                a.href = url;
+                a.download = `${filename}${extension}`;
+                document.body.appendChild(a);
+                a.click();
+                document.body.removeChild(a);
+
+                // Delay URL revocation to ensure download completes
+                if (!url.startsWith("data:")) {
+                    setTimeout(() => URL.revokeObjectURL(url), 100);
+                }
+            },
+            format,
         };
+
+        // Export diagram - callback will be handled in handleDiagramExport
+        drawioRef.current.exportDiagram({ format: drawioFormat });
+    };
+
+    // Log save event to Langfuse (just flags the trace, doesn't send content)
+    const logSaveToLangfuse = async (filename: string, format: string, sessionId?: string) => {
+        try {
+            await fetch("/api/log-save", {
+                method: "POST",
+                headers: { "Content-Type": "application/json" },
+                body: JSON.stringify({ filename, format, sessionId }),
+            });
+        } catch (error) {
+            console.warn("Failed to log save to Langfuse:", error);
+        }
     };
 
     return (

docs/ai-providers.md

@@ -0,0 +1,141 @@
+# AI Provider Configuration
+
+This guide explains how to configure different AI model providers for next-ai-draw-io.
+
+## Quick Start
+
+1. Copy `.env.example` to `.env.local`
+2. Set your API key for your chosen provider
+3. Set `AI_MODEL` to your desired model
+4. Run `npm run dev`
+
+## Supported Providers
+
+### Google Gemini
+
+```bash
+GOOGLE_GENERATIVE_AI_API_KEY=your_api_key
+AI_MODEL=gemini-2.0-flash
+```
+
+Optional custom endpoint:
+
+```bash
+GOOGLE_BASE_URL=https://your-custom-endpoint
+```
+
+### OpenAI
+
+```bash
+OPENAI_API_KEY=your_api_key
+AI_MODEL=gpt-4o
+```
+
+Optional custom endpoint (for OpenAI-compatible services):
+
+```bash
+OPENAI_BASE_URL=https://your-custom-endpoint/v1
+```
+
+### Anthropic
+
+```bash
+ANTHROPIC_API_KEY=your_api_key
+AI_MODEL=claude-sonnet-4-5-20250514
+```
+
+Optional custom endpoint:
+
+```bash
+ANTHROPIC_BASE_URL=https://your-custom-endpoint
+```
+
+### DeepSeek
+
+```bash
+DEEPSEEK_API_KEY=your_api_key
+AI_MODEL=deepseek-chat
+```
+
+Optional custom endpoint:
+
+```bash
+DEEPSEEK_BASE_URL=https://your-custom-endpoint
+```
+
+### Azure OpenAI
+
+```bash
+AZURE_API_KEY=your_api_key
+AI_MODEL=your-deployment-name
+```
+
+Optional custom endpoint:
+
+```bash
+AZURE_BASE_URL=https://your-resource.openai.azure.com
+```
+
+### AWS Bedrock
+
+```bash
+AWS_REGION=us-west-2
+AWS_ACCESS_KEY_ID=your_access_key_id
+AWS_SECRET_ACCESS_KEY=your_secret_access_key
+AI_MODEL=anthropic.claude-sonnet-4-5-20250514-v1:0
+```
+
+Note: On AWS (Amplify, Lambda, EC2 with IAM role), credentials are automatically obtained from the IAM role.
+
+### OpenRouter
+
+```bash
+OPENROUTER_API_KEY=your_api_key
+AI_MODEL=anthropic/claude-sonnet-4
+```
+
+Optional custom endpoint:
+
+```bash
+OPENROUTER_BASE_URL=https://your-custom-endpoint
+```
+
+### Ollama (Local)
+
+```bash
+AI_PROVIDER=ollama
+AI_MODEL=llama3.2
+```
+
+Optional custom URL:
+
+```bash
+OLLAMA_BASE_URL=http://localhost:11434
+```
+
+## Auto-Detection
+
+If you only configure **one** provider's API key, the system will automatically detect and use that provider. No need to set `AI_PROVIDER`.
+
+If you configure **multiple** API keys, you must explicitly set `AI_PROVIDER`:
+
+```bash
+AI_PROVIDER=google  # or: openai, anthropic, deepseek, azure, bedrock, openrouter, ollama
+```
+
+## Model Capability Requirements
+
+This task requires exceptionally strong model capabilities, as it involves generating long-form text with strict formatting constraints (draw.io XML).
+
+**Recommended models**:
+
+-   Claude Sonnet 4.5 / Opus 4.5
+
+**Note on Ollama**: While Ollama is supported as a provider, it's generally not practical for this use case unless you're running high-capability models like DeepSeek R1 or Qwen3-235B locally.
+
+## Recommendations
+
+-   **Best experience**: Use models with vision support (GPT-4o, Claude, Gemini) for image-to-diagram features
+-   **Budget-friendly**: DeepSeek offers competitive pricing
+-   **Privacy**: Use Ollama for fully local, offline operation (requires powerful hardware)
+-   **Flexibility**: OpenRouter provides access to many models through a single API

env.example

@@ -47,3 +47,6 @@ AI_MODEL=global.anthropic.claude-sonnet-4-5-20250929-v1:0
 # LANGFUSE_PUBLIC_KEY=pk-lf-...
 # LANGFUSE_SECRET_KEY=sk-lf-...
 # LANGFUSE_BASEURL=https://cloud.langfuse.com  # EU region, use https://us.cloud.langfuse.com for US
+
+# Access Control (Optional)
+# ACCESS_CODE_LIST=your-secret-code,another-code

instrumentation.ts

@@ -12,11 +12,24 @@ export function register() {
     publicKey: process.env.LANGFUSE_PUBLIC_KEY,
     secretKey: process.env.LANGFUSE_SECRET_KEY,
     baseUrl: process.env.LANGFUSE_BASEURL,
+    // Filter out Next.js HTTP request spans so AI SDK spans become root traces
+    shouldExportSpan: ({ otelSpan }) => {
+      const spanName = otelSpan.name;
+      // Skip Next.js HTTP infrastructure spans
+      if (spanName.startsWith('POST /') ||
+          spanName.startsWith('GET /') ||
+          spanName.includes('BaseServer') ||
+          spanName.includes('handleRequest')) {
+        return false;
+      }
+      return true;
+    },
   });
 
   const tracerProvider = new NodeTracerProvider({
     spanProcessors: [langfuseSpanProcessor],
   });
 
+  // Register globally so AI SDK's telemetry also uses this processor
   tracerProvider.register();
 }

lib/ai-providers.ts

@@ -1,4 +1,5 @@
-import { bedrock } from '@ai-sdk/amazon-bedrock';
+import { createAmazonBedrock } from '@ai-sdk/amazon-bedrock';
+import { fromNodeProviderChain } from '@aws-sdk/credential-providers';
 import { openai, createOpenAI } from '@ai-sdk/openai';
 import { createAnthropic } from '@ai-sdk/anthropic';
 import { google, createGoogleGenerativeAI } from '@ai-sdk/google';
@@ -21,6 +22,7 @@ interface ModelConfig {
   model: any;
   providerOptions?: any;
   headers?: Record<string, string>;
+  modelId: string;
 }
 
 // Bedrock provider options for Anthropic beta features
@@ -35,22 +37,47 @@ const ANTHROPIC_BETA_HEADERS = {
   'anthropic-beta': 'fine-grained-tool-streaming-2025-05-14',
 };
 
+// Map of provider to required environment variable
+const PROVIDER_ENV_VARS: Record<ProviderName, string | null> = {
+  bedrock: null, // AWS SDK auto-uses IAM role on AWS, or env vars locally
+  openai: 'OPENAI_API_KEY',
+  anthropic: 'ANTHROPIC_API_KEY',
+  google: 'GOOGLE_GENERATIVE_AI_API_KEY',
+  azure: 'AZURE_API_KEY',
+  ollama: null, // No credentials needed for local Ollama
+  openrouter: 'OPENROUTER_API_KEY',
+  deepseek: 'DEEPSEEK_API_KEY',
+};
+
+/**
+ * Auto-detect provider based on available API keys
+ * Returns the provider if exactly one is configured, otherwise null
+ */
+function detectProvider(): ProviderName | null {
+  const configuredProviders: ProviderName[] = [];
+
+  for (const [provider, envVar] of Object.entries(PROVIDER_ENV_VARS)) {
+    if (envVar === null) {
+      // Skip ollama - it doesn't require credentials
+      continue;
+    }
+    if (process.env[envVar]) {
+      configuredProviders.push(provider as ProviderName);
+    }
+  }
+
+  if (configuredProviders.length === 1) {
+    return configuredProviders[0];
+  }
+
+  return null;
+}
+
 /**
  * Validate that required API keys are present for the selected provider
  */
 function validateProviderCredentials(provider: ProviderName): void {
-  const requiredEnvVars: Record<ProviderName, string | null> = {
-    bedrock: 'AWS_ACCESS_KEY_ID',
-    openai: 'OPENAI_API_KEY',
-    anthropic: 'ANTHROPIC_API_KEY',
-    google: 'GOOGLE_GENERATIVE_AI_API_KEY',
-    azure: 'AZURE_API_KEY',
-    ollama: null, // No credentials needed for local Ollama
-    openrouter: 'OPENROUTER_API_KEY',
-    deepseek: 'DEEPSEEK_API_KEY',
-  };
-
-  const requiredVar = requiredEnvVars[provider];
+  const requiredVar = PROVIDER_ENV_VARS[provider];
   if (requiredVar && !process.env[requiredVar]) {
     throw new Error(
       `${requiredVar} environment variable is required for ${provider} provider. ` +
@@ -79,7 +106,6 @@ function validateProviderCredentials(provider: ProviderName): void {
  * - DEEPSEEK_BASE_URL: DeepSeek endpoint (optional)
  */
 export function getAIModel(): ModelConfig {
-  const provider = (process.env.AI_PROVIDER || 'bedrock') as ProviderName;
   const modelId = process.env.AI_MODEL;
 
   if (!modelId) {
@@ -88,10 +114,45 @@ export function getAIModel(): ModelConfig {
     );
   }
 
+  // Determine provider: explicit config > auto-detect > error
+  let provider: ProviderName;
+  if (process.env.AI_PROVIDER) {
+    provider = process.env.AI_PROVIDER as ProviderName;
+  } else {
+    const detected = detectProvider();
+    if (detected) {
+      provider = detected;
+      console.log(`[AI Provider] Auto-detected provider: ${provider}`);
+    } else {
+      // List configured providers for better error message
+      const configured = Object.entries(PROVIDER_ENV_VARS)
+        .filter(([, envVar]) => envVar && process.env[envVar as string])
+        .map(([p]) => p);
+
+      if (configured.length === 0) {
+        throw new Error(
+          `No AI provider configured. Please set one of the following API keys in your .env.local file:\n` +
+          `- DEEPSEEK_API_KEY for DeepSeek\n` +
+          `- OPENAI_API_KEY for OpenAI\n` +
+          `- ANTHROPIC_API_KEY for Anthropic\n` +
+          `- GOOGLE_GENERATIVE_AI_API_KEY for Google\n` +
+          `- AWS_ACCESS_KEY_ID for Bedrock\n` +
+          `- OPENROUTER_API_KEY for OpenRouter\n` +
+          `- AZURE_API_KEY for Azure\n` +
+          `Or set AI_PROVIDER=ollama for local Ollama.`
+        );
+      } else {
+        throw new Error(
+          `Multiple AI providers configured (${configured.join(', ')}). ` +
+          `Please set AI_PROVIDER to specify which one to use.`
+        );
+      }
+    }
+  }
+
   // Validate provider credentials
   validateProviderCredentials(provider);
 
-  // Log initialization for debugging
   console.log(`[AI Provider] Initializing ${provider} with model: ${modelId}`);
 
   let model: any;
@@ -99,13 +160,20 @@ export function getAIModel(): ModelConfig {
   let headers: Record<string, string> | undefined = undefined;
 
   switch (provider) {
-    case 'bedrock':
-      model = bedrock(modelId);
+    case 'bedrock': {
+      // Use credential provider chain for IAM role support (Amplify, Lambda, etc.)
+      // Falls back to env vars (AWS_ACCESS_KEY_ID, AWS_SECRET_ACCESS_KEY) for local dev
+      const bedrockProvider = createAmazonBedrock({
+        region: process.env.AWS_REGION || 'us-west-2',
+        credentialProvider: fromNodeProviderChain(),
+      });
+      model = bedrockProvider(modelId);
       // Add Anthropic beta options if using Claude models via Bedrock
       if (modelId.includes('anthropic.claude')) {
         providerOptions = BEDROCK_ANTHROPIC_BETA;
       }
       break;
+    }
 
     case 'openai':
       if (process.env.OPENAI_BASE_URL) {
@@ -191,10 +259,5 @@ export function getAIModel(): ModelConfig {
       );
   }
 
-  // Log if provider options or headers are being applied
-  if (providerOptions || headers) {
-    console.log('[AI Provider] Applying provider-specific options/headers');
-  }
-
-  return { model, providerOptions, headers };
+  return { model, providerOptions, headers, modelId };
 }

lib/cached-responses.ts

@@ -12,117 +12,117 @@ export const CACHED_EXAMPLE_RESPONSES: CachedResponse[] = [
   <mxCell id="0"/>
   <mxCell id="1" parent="0"/>
 
-  <!-- Title -->
+
   <mxCell id="title" value="Transformer Architecture" style="text;html=1;strokeColor=none;fillColor=none;align=center;verticalAlign=middle;whiteSpace=wrap;rounded=0;fontSize=20;fontStyle=1;" vertex="1" parent="1">
     <mxGeometry x="300" y="20" width="250" height="30" as="geometry"/>
   </mxCell>
 
-  <!-- Input Embedding (Left - Encoder Side) -->
+
   <mxCell id="input_embed" value="Input Embedding" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#dae8fc;strokeColor=#6c8ebf;fontSize=11;" vertex="1" parent="1">
     <mxGeometry x="80" y="480" width="120" height="40" as="geometry"/>
   </mxCell>
 
-  <!-- Positional Encoding (Left) -->
+
   <mxCell id="pos_enc_left" value="Positional Encoding" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#dae8fc;strokeColor=#6c8ebf;fontSize=11;" vertex="1" parent="1">
     <mxGeometry x="80" y="420" width="120" height="40" as="geometry"/>
   </mxCell>
 
-  <!-- Encoder Stack -->
+
   <mxCell id="encoder_box" value="ENCODER" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#e1d5e7;strokeColor=#9673a6;verticalAlign=top;fontSize=12;fontStyle=1;" vertex="1" parent="1">
     <mxGeometry x="60" y="180" width="160" height="220" as="geometry"/>
   </mxCell>
 
-  <!-- Multi-Head Attention (Encoder) -->
+
   <mxCell id="mha_enc" value="Multi-Head&#xa;Attention" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#fff2cc;strokeColor=#d6b656;fontSize=10;" vertex="1" parent="1">
     <mxGeometry x="80" y="330" width="120" height="50" as="geometry"/>
   </mxCell>
 
-  <!-- Add & Norm 1 (Encoder) -->
+
   <mxCell id="add_norm1_enc" value="Add &amp; Norm" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#d5e8d4;strokeColor=#82b366;fontSize=10;" vertex="1" parent="1">
     <mxGeometry x="80" y="280" width="120" height="30" as="geometry"/>
   </mxCell>
 
-  <!-- Feed Forward (Encoder) -->
+
   <mxCell id="ff_enc" value="Feed Forward" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#fff2cc;strokeColor=#d6b656;fontSize=10;" vertex="1" parent="1">
     <mxGeometry x="80" y="240" width="120" height="30" as="geometry"/>
   </mxCell>
 
-  <!-- Add & Norm 2 (Encoder) -->
+
   <mxCell id="add_norm2_enc" value="Add &amp; Norm" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#d5e8d4;strokeColor=#82b366;fontSize=10;" vertex="1" parent="1">
     <mxGeometry x="80" y="200" width="120" height="30" as="geometry"/>
   </mxCell>
 
-  <!-- Nx label for encoder -->
+
   <mxCell id="nx_enc" value="Nx" style="text;html=1;strokeColor=none;fillColor=none;align=center;verticalAlign=middle;whiteSpace=wrap;rounded=0;fontSize=11;fontStyle=2;" vertex="1" parent="1">
     <mxGeometry x="30" y="275" width="30" height="30" as="geometry"/>
   </mxCell>
 
-  <!-- Output Embedding (Right - Decoder Side) -->
+
   <mxCell id="output_embed" value="Output Embedding" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#dae8fc;strokeColor=#6c8ebf;fontSize=11;" vertex="1" parent="1">
     <mxGeometry x="650" y="480" width="120" height="40" as="geometry"/>
   </mxCell>
 
-  <!-- Positional Encoding (Right) -->
+
   <mxCell id="pos_enc_right" value="Positional Encoding" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#dae8fc;strokeColor=#6c8ebf;fontSize=11;" vertex="1" parent="1">
     <mxGeometry x="650" y="420" width="120" height="40" as="geometry"/>
   </mxCell>
 
-  <!-- Decoder Stack -->
+
   <mxCell id="decoder_box" value="DECODER" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#ffe6cc;strokeColor=#d79b00;verticalAlign=top;fontSize=12;fontStyle=1;" vertex="1" parent="1">
     <mxGeometry x="630" y="140" width="160" height="260" as="geometry"/>
   </mxCell>
 
-  <!-- Masked Multi-Head Attention (Decoder) -->
+
   <mxCell id="masked_mha_dec" value="Masked Multi-Head&#xa;Attention" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#fff2cc;strokeColor=#d6b656;fontSize=10;" vertex="1" parent="1">
     <mxGeometry x="650" y="340" width="120" height="50" as="geometry"/>
   </mxCell>
 
-  <!-- Add & Norm 1 (Decoder) -->
+
   <mxCell id="add_norm1_dec" value="Add &amp; Norm" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#d5e8d4;strokeColor=#82b366;fontSize=10;" vertex="1" parent="1">
     <mxGeometry x="650" y="290" width="120" height="30" as="geometry"/>
   </mxCell>
 
-  <!-- Multi-Head Attention (Decoder - Cross Attention) -->
+
   <mxCell id="mha_dec" value="Multi-Head&#xa;Attention" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#fff2cc;strokeColor=#d6b656;fontSize=10;" vertex="1" parent="1">
     <mxGeometry x="650" y="240" width="120" height="40" as="geometry"/>
   </mxCell>
 
-  <!-- Add & Norm 2 (Decoder) -->
+
   <mxCell id="add_norm2_dec" value="Add &amp; Norm" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#d5e8d4;strokeColor=#82b366;fontSize=10;" vertex="1" parent="1">
     <mxGeometry x="650" y="200" width="120" height="30" as="geometry"/>
   </mxCell>
 
-  <!-- Feed Forward (Decoder) -->
+
   <mxCell id="ff_dec" value="Feed Forward" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#fff2cc;strokeColor=#d6b656;fontSize=10;" vertex="1" parent="1">
     <mxGeometry x="650" y="160" width="120" height="30" as="geometry"/>
   </mxCell>
 
-  <!-- Add & Norm 3 (Decoder) -->
+
   <mxCell id="add_norm3_dec" value="Add &amp; Norm" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#d5e8d4;strokeColor=#82b366;fontSize=10;" vertex="1" parent="1">
     <mxGeometry x="650" y="120" width="120" height="30" as="geometry"/>
   </mxCell>
 
-  <!-- Nx label for decoder -->
+
   <mxCell id="nx_dec" value="Nx" style="text;html=1;strokeColor=none;fillColor=none;align=center;verticalAlign=middle;whiteSpace=wrap;rounded=0;fontSize=11;fontStyle=2;" vertex="1" parent="1">
     <mxGeometry x="790" y="255" width="30" height="30" as="geometry"/>
   </mxCell>
 
-  <!-- Linear -->
+
   <mxCell id="linear" value="Linear" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#f8cecc;strokeColor=#b85450;fontSize=11;" vertex="1" parent="1">
     <mxGeometry x="650" y="80" width="120" height="30" as="geometry"/>
   </mxCell>
 
-  <!-- Softmax -->
+
   <mxCell id="softmax" value="Softmax" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#f8cecc;strokeColor=#b85450;fontSize=11;" vertex="1" parent="1">
     <mxGeometry x="650" y="40" width="120" height="30" as="geometry"/>
   </mxCell>
 
-  <!-- Output Probabilities -->
+
   <mxCell id="output" value="Output Probabilities" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#dae8fc;strokeColor=#6c8ebf;fontSize=11;fontStyle=1;" vertex="1" parent="1">
     <mxGeometry x="640" y="0" width="140" height="30" as="geometry"/>
   </mxCell>
 
-  <!-- Animated Connectors - Encoder Side -->
+
   <mxCell id="conn1" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;exitX=0.5;exitY=0;exitDx=0;exitDy=0;entryX=0.5;entryY=1;entryDx=0;entryDy=0;strokeWidth=2;strokeColor=#6c8ebf;flowAnimation=1;" edge="1" parent="1" source="input_embed" target="pos_enc_left">
     <mxGeometry relative="1" as="geometry"/>
   </mxCell>
@@ -143,7 +143,7 @@ export const CACHED_EXAMPLE_RESPONSES: CachedResponse[] = [
     <mxGeometry relative="1" as="geometry"/>
   </mxCell>
 
-  <!-- Encoder to Decoder Cross Attention -->
+
   <mxCell id="conn_cross" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;exitX=1;exitY=0.5;exitDx=0;exitDy=0;entryX=0;entryY=0.5;entryDx=0;entryDy=0;strokeWidth=3;strokeColor=#9673a6;flowAnimation=1;dashed=1;" edge="1" parent="1" source="add_norm2_enc" target="mha_dec">
     <mxGeometry relative="1" as="geometry">
       <Array as="points">
@@ -158,7 +158,7 @@ export const CACHED_EXAMPLE_RESPONSES: CachedResponse[] = [
     </mxGeometry>
   </mxCell>
 
-  <!-- Animated Connectors - Decoder Side -->
+
   <mxCell id="conn6" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;exitX=0.5;exitY=0;exitDx=0;exitDy=0;entryX=0.5;entryY=1;entryDx=0;entryDy=0;strokeWidth=2;strokeColor=#d79b00;flowAnimation=1;" edge="1" parent="1" source="output_embed" target="pos_enc_right">
     <mxGeometry relative="1" as="geometry"/>
   </mxCell>
@@ -199,7 +199,7 @@ export const CACHED_EXAMPLE_RESPONSES: CachedResponse[] = [
     <mxGeometry relative="1" as="geometry"/>
   </mxCell>
 
-  <!-- Residual Connections (Encoder) -->
+
   <mxCell id="res1_enc" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;exitX=0;exitY=0.5;exitDx=0;exitDy=0;entryX=0;entryY=0.5;entryDx=0;entryDy=0;strokeWidth=1.5;strokeColor=#999999;dashed=1;flowAnimation=1;" edge="1" parent="1" source="mha_enc" target="add_norm1_enc">
     <mxGeometry relative="1" as="geometry">
       <Array as="points">
@@ -218,7 +218,7 @@ export const CACHED_EXAMPLE_RESPONSES: CachedResponse[] = [
     </mxGeometry>
   </mxCell>
 
-  <!-- Residual Connections (Decoder) -->
+
   <mxCell id="res1_dec" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;exitX=1;exitY=0.5;exitDx=0;exitDy=0;entryX=1;entryY=0.5;entryDx=0;entryDy=0;strokeWidth=1.5;strokeColor=#999999;dashed=1;flowAnimation=1;" edge="1" parent="1" source="masked_mha_dec" target="add_norm1_dec">
     <mxGeometry relative="1" as="geometry">
       <Array as="points">
@@ -246,7 +246,7 @@ export const CACHED_EXAMPLE_RESPONSES: CachedResponse[] = [
     </mxGeometry>
   </mxCell>
 
-  <!-- Input/Output Labels -->
+
   <mxCell id="input_label" value="Inputs" style="text;html=1;strokeColor=none;fillColor=none;align=center;verticalAlign=middle;whiteSpace=wrap;rounded=0;fontSize=12;fontStyle=1;" vertex="1" parent="1">
     <mxGeometry x="110" y="530" width="60" height="20" as="geometry"/>
   </mxCell>
@@ -263,37 +263,37 @@ export const CACHED_EXAMPLE_RESPONSES: CachedResponse[] = [
   <mxCell id="0"/>
   <mxCell id="1" parent="0"/>
 
-  <!-- AWS Cloud Container -->
+
   <mxCell id="2" value="AWS" style="sketch=0;outlineConnect=0;gradientColor=none;html=1;whiteSpace=wrap;fontSize=12;fontStyle=0;container=1;pointerEvents=0;collapsible=0;recursiveResize=0;shape=mxgraph.aws4.group;grIcon=mxgraph.aws4.group_aws_cloud;strokeColor=#232F3E;fillColor=none;verticalAlign=top;align=left;spacingLeft=30;fontColor=#232F3E;dashed=0;rounded=1;arcSize=5;" vertex="1" parent="1">
     <mxGeometry x="340" y="40" width="880" height="520" as="geometry"/>
   </mxCell>
 
-  <!-- User -->
+
   <mxCell id="3" value="User" style="sketch=0;outlineConnect=0;fontColor=#232F3E;gradientColor=none;fillColor=#232F3D;strokeColor=none;dashed=0;verticalLabelPosition=bottom;verticalAlign=top;align=center;html=1;fontSize=14;fontStyle=0;aspect=fixed;pointerEvents=1;shape=mxgraph.aws4.user;rounded=1;" vertex="1" parent="1">
     <mxGeometry x="80" y="240" width="78" height="78" as="geometry"/>
   </mxCell>
 
-  <!-- EC2 Instance -->
+
   <mxCell id="4" value="EC2" style="sketch=0;points=[[0,0,0],[0.25,0,0],[0.5,0,0],[0.75,0,0],[1,0,0],[0,1,0],[0.25,1,0],[0.5,1,0],[0.75,1,0],[1,1,0],[0,0.25,0],[0,0.5,0],[0,0.75,0],[1,0.25,0],[1,0.5,0],[1,0.75,0]];outlineConnect=0;fontColor=#232F3E;fillColor=#ED7100;strokeColor=#ffffff;dashed=0;verticalLabelPosition=bottom;verticalAlign=top;align=center;html=1;fontSize=14;fontStyle=0;aspect=fixed;shape=mxgraph.aws4.resourceIcon;resIcon=mxgraph.aws4.ec2;rounded=1;" vertex="1" parent="1">
     <mxGeometry x="560" y="240" width="78" height="78" as="geometry"/>
   </mxCell>
 
-  <!-- S3 Bucket -->
+
   <mxCell id="5" value="S3" style="sketch=0;points=[[0,0,0],[0.25,0,0],[0.5,0,0],[0.75,0,0],[1,0,0],[0,1,0],[0.25,1,0],[0.5,1,0],[0.75,1,0],[1,1,0],[0,0.25,0],[0,0.5,0],[0,0.75,0],[1,0.25,0],[1,0.5,0],[1,0.75,0]];outlineConnect=0;fontColor=#232F3E;fillColor=#7AA116;strokeColor=#ffffff;dashed=0;verticalLabelPosition=bottom;verticalAlign=top;align=center;html=1;fontSize=14;fontStyle=0;aspect=fixed;shape=mxgraph.aws4.resourceIcon;resIcon=mxgraph.aws4.s3;rounded=1;" vertex="1" parent="1">
     <mxGeometry x="960" y="120" width="78" height="78" as="geometry"/>
   </mxCell>
 
-  <!-- Bedrock -->
+
   <mxCell id="6" value="bedrock" style="sketch=0;points=[[0,0,0],[0.25,0,0],[0.5,0,0],[0.75,0,0],[1,0,0],[0,1,0],[0.25,1,0],[0.5,1,0],[0.75,1,0],[1,1,0],[0,0.25,0],[0,0.5,0],[0,0.75,0],[1,0.25,0],[1,0.5,0],[1,0.75,0]];outlineConnect=0;fontColor=#232F3E;fillColor=#01A88D;strokeColor=#ffffff;dashed=0;verticalLabelPosition=bottom;verticalAlign=top;align=center;html=1;fontSize=14;fontStyle=0;aspect=fixed;shape=mxgraph.aws4.resourceIcon;resIcon=mxgraph.aws4.bedrock;rounded=1;" vertex="1" parent="1">
     <mxGeometry x="960" y="260" width="78" height="78" as="geometry"/>
   </mxCell>
 
-  <!-- DynamoDB -->
+
   <mxCell id="7" value="DynamoDB" style="sketch=0;points=[[0,0,0],[0.25,0,0],[0.5,0,0],[0.75,0,0],[1,0,0],[0,1,0],[0.25,1,0],[0.5,1,0],[0.75,1,0],[1,1,0],[0,0.25,0],[0,0.5,0],[0,0.75,0],[1,0.25,0],[1,0.5,0],[1,0.75,0]];outlineConnect=0;fontColor=#232F3E;fillColor=#C925D1;strokeColor=#ffffff;dashed=0;verticalLabelPosition=bottom;verticalAlign=top;align=center;html=1;fontSize=14;fontStyle=0;aspect=fixed;shape=mxgraph.aws4.resourceIcon;resIcon=mxgraph.aws4.dynamodb;rounded=1;" vertex="1" parent="1">
     <mxGeometry x="960" y="400" width="78" height="78" as="geometry"/>
   </mxCell>
 
-  <!-- Arrow: User to EC2 -->
+
   <mxCell id="8" value="" style="endArrow=classic;html=1;rounded=0;strokeColor=#232F3E;strokeWidth=2;exitX=1;exitY=0.5;exitDx=0;exitDy=0;exitPerimeter=0;entryX=0;entryY=0.5;entryDx=0;entryDy=0;entryPerimeter=0;" edge="1" parent="1" source="3" target="4">
     <mxGeometry width="50" height="50" relative="1" as="geometry">
       <mxPoint x="400" y="350" as="sourcePoint"/>
@@ -301,7 +301,7 @@ export const CACHED_EXAMPLE_RESPONSES: CachedResponse[] = [
     </mxGeometry>
   </mxCell>
 
-  <!-- Arrow: EC2 to S3 -->
+
   <mxCell id="9" value="" style="endArrow=classic;html=1;rounded=0;strokeColor=#232F3E;strokeWidth=2;exitX=1;exitY=0.25;exitDx=0;exitDy=0;exitPerimeter=0;entryX=0;entryY=0.5;entryDx=0;entryDy=0;entryPerimeter=0;" edge="1" parent="1" source="4" target="5">
     <mxGeometry width="50" height="50" relative="1" as="geometry">
       <mxPoint x="700" y="350" as="sourcePoint"/>
@@ -309,7 +309,7 @@ export const CACHED_EXAMPLE_RESPONSES: CachedResponse[] = [
     </mxGeometry>
   </mxCell>
 
-  <!-- Arrow: EC2 to Bedrock -->
+
   <mxCell id="10" value="" style="endArrow=classic;html=1;rounded=0;strokeColor=#232F3E;strokeWidth=2;exitX=1;exitY=0.5;exitDx=0;exitDy=0;exitPerimeter=0;entryX=0;entryY=0.5;entryDx=0;entryDy=0;entryPerimeter=0;" edge="1" parent="1" source="4" target="6">
     <mxGeometry width="50" height="50" relative="1" as="geometry">
       <mxPoint x="700" y="350" as="sourcePoint"/>
@@ -317,7 +317,7 @@ export const CACHED_EXAMPLE_RESPONSES: CachedResponse[] = [
     </mxGeometry>
   </mxCell>
 
-  <!-- Arrow: EC2 to DynamoDB -->
+
   <mxCell id="11" value="" style="endArrow=classic;html=1;rounded=0;strokeColor=#232F3E;strokeWidth=2;exitX=1;exitY=0.75;exitDx=0;exitDy=0;exitPerimeter=0;entryX=0;entryY=0.5;entryDx=0;entryDy=0;entryPerimeter=0;" edge="1" parent="1" source="4" target="7">
     <mxGeometry width="50" height="50" relative="1" as="geometry">
       <mxPoint x="700" y="350" as="sourcePoint"/>
@@ -333,61 +333,61 @@ export const CACHED_EXAMPLE_RESPONSES: CachedResponse[] = [
   <mxCell id="0"/>
   <mxCell id="1" parent="0"/>
 
-  <!-- Start: Lamp doesn't work -->
+
   <mxCell id="2" value="Lamp doesn't work" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#ffcccc;strokeColor=#000000;strokeWidth=2;fontSize=18;fontStyle=0;" vertex="1" parent="1">
     <mxGeometry x="140" y="40" width="180" height="60" as="geometry"/>
   </mxCell>
 
-  <!-- Arrow from start to first decision -->
+
   <mxCell id="3" value="" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;strokeColor=#000000;strokeWidth=2;endArrow=block;endFill=1;" edge="1" parent="1" source="2" target="4">
     <mxGeometry relative="1" as="geometry"/>
   </mxCell>
 
-  <!-- Decision: Lamp plugged in? -->
+
   <mxCell id="4" value="Lamp&lt;br&gt;plugged in?" style="rhombus;whiteSpace=wrap;html=1;fillColor=#ffff99;strokeColor=#000000;strokeWidth=2;fontSize=18;fontStyle=0;" vertex="1" parent="1">
     <mxGeometry x="130" y="150" width="200" height="200" as="geometry"/>
   </mxCell>
 
-  <!-- Arrow to Plug in lamp (No) -->
+
   <mxCell id="5" value="No" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;strokeColor=#000000;strokeWidth=2;endArrow=block;endFill=1;fontSize=16;" edge="1" parent="1" source="4" target="6">
     <mxGeometry x="-0.2" relative="1" as="geometry">
       <mxPoint as="offset"/>
     </mxGeometry>
   </mxCell>
 
-  <!-- Action: Plug in lamp -->
+
   <mxCell id="6" value="Plug in lamp" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#99ff99;strokeColor=#000000;strokeWidth=2;fontSize=18;fontStyle=0;" vertex="1" parent="1">
     <mxGeometry x="420" y="220" width="200" height="60" as="geometry"/>
   </mxCell>
 
-  <!-- Arrow down to second decision (Yes) -->
+
   <mxCell id="7" value="Yes" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;strokeColor=#000000;strokeWidth=2;endArrow=block;endFill=1;fontSize=16;" edge="1" parent="1" source="4" target="8">
     <mxGeometry relative="1" as="geometry"/>
   </mxCell>
 
-  <!-- Decision: Bulb burned out? -->
+
   <mxCell id="8" value="Bulb&lt;br&gt;burned out?" style="rhombus;whiteSpace=wrap;html=1;fillColor=#ffff99;strokeColor=#000000;strokeWidth=2;fontSize=18;fontStyle=0;" vertex="1" parent="1">
     <mxGeometry x="130" y="400" width="200" height="200" as="geometry"/>
   </mxCell>
 
-  <!-- Arrow to Replace bulb (Yes) -->
+
   <mxCell id="9" value="Yes" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;strokeColor=#000000;strokeWidth=2;endArrow=block;endFill=1;fontSize=16;" edge="1" parent="1" source="8" target="10">
     <mxGeometry x="-0.2" relative="1" as="geometry">
       <mxPoint as="offset"/>
     </mxGeometry>
   </mxCell>
 
-  <!-- Action: Replace bulb -->
+
   <mxCell id="10" value="Replace bulb" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#99ff99;strokeColor=#000000;strokeWidth=2;fontSize=18;fontStyle=0;" vertex="1" parent="1">
     <mxGeometry x="420" y="470" width="200" height="60" as="geometry"/>
   </mxCell>
 
-  <!-- Arrow down to Repair lamp (No) -->
+
   <mxCell id="11" value="No" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;strokeColor=#000000;strokeWidth=2;endArrow=block;endFill=1;fontSize=16;" edge="1" parent="1" source="8" target="12">
     <mxGeometry relative="1" as="geometry"/>
   </mxCell>
 
-  <!-- Action: Repair lamp -->
+
   <mxCell id="12" value="Repair lamp" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#99ff99;strokeColor=#000000;strokeWidth=2;fontSize=18;fontStyle=0;" vertex="1" parent="1">
     <mxGeometry x="130" y="650" width="200" height="60" as="geometry"/>
   </mxCell>
@@ -400,47 +400,47 @@ export const CACHED_EXAMPLE_RESPONSES: CachedResponse[] = [
   <mxCell id="0"/>
   <mxCell id="1" parent="0"/>
 
-  <!-- Cat's head -->
+
   <mxCell id="2" value="" style="ellipse;whiteSpace=wrap;html=1;aspect=fixed;fillColor=#FFE6CC;strokeColor=#000000;strokeWidth=2;" vertex="1" parent="1">
     <mxGeometry x="300" y="150" width="120" height="120" as="geometry"/>
   </mxCell>
 
-  <!-- Left ear -->
+
   <mxCell id="3" value="" style="triangle;whiteSpace=wrap;html=1;fillColor=#FFE6CC;strokeColor=#000000;strokeWidth=2;rotation=30;" vertex="1" parent="1">
     <mxGeometry x="280" y="120" width="50" height="60" as="geometry"/>
   </mxCell>
 
-  <!-- Right ear -->
+
   <mxCell id="4" value="" style="triangle;whiteSpace=wrap;html=1;fillColor=#FFE6CC;strokeColor=#000000;strokeWidth=2;rotation=-30;" vertex="1" parent="1">
     <mxGeometry x="390" y="120" width="50" height="60" as="geometry"/>
   </mxCell>
 
-  <!-- Left ear inner -->
+
   <mxCell id="5" value="" style="triangle;whiteSpace=wrap;html=1;fillColor=#FFB6C1;strokeColor=none;rotation=30;" vertex="1" parent="1">
     <mxGeometry x="290" y="135" width="30" height="35" as="geometry"/>
   </mxCell>
 
-  <!-- Right ear inner -->
+
   <mxCell id="6" value="" style="triangle;whiteSpace=wrap;html=1;fillColor=#FFB6C1;strokeColor=none;rotation=-30;" vertex="1" parent="1">
     <mxGeometry x="400" y="135" width="30" height="35" as="geometry"/>
   </mxCell>
 
-  <!-- Left eye -->
+
   <mxCell id="7" value="" style="ellipse;whiteSpace=wrap;html=1;aspect=fixed;fillColor=#000000;strokeColor=#000000;" vertex="1" parent="1">
     <mxGeometry x="325" y="185" width="15" height="15" as="geometry"/>
   </mxCell>
 
-  <!-- Right eye -->
+
   <mxCell id="8" value="" style="ellipse;whiteSpace=wrap;html=1;aspect=fixed;fillColor=#000000;strokeColor=#000000;" vertex="1" parent="1">
     <mxGeometry x="380" y="185" width="15" height="15" as="geometry"/>
   </mxCell>
 
-  <!-- Nose -->
+
   <mxCell id="9" value="" style="triangle;whiteSpace=wrap;html=1;fillColor=#FFB6C1;strokeColor=#000000;strokeWidth=1;rotation=180;" vertex="1" parent="1">
     <mxGeometry x="350" y="210" width="20" height="15" as="geometry"/>
   </mxCell>
 
-  <!-- Mouth left -->
+
   <mxCell id="10" value="" style="curved=1;endArrow=none;html=1;strokeColor=#000000;strokeWidth=2;exitX=0.5;exitY=1;exitDx=0;exitDy=0;" edge="1" parent="1">
     <mxGeometry width="50" height="50" relative="1" as="geometry">
       <mxPoint x="360" y="220" as="sourcePoint"/>
@@ -451,7 +451,7 @@ export const CACHED_EXAMPLE_RESPONSES: CachedResponse[] = [
     </mxGeometry>
   </mxCell>
 
-  <!-- Mouth right -->
+
   <mxCell id="11" value="" style="curved=1;endArrow=none;html=1;strokeColor=#000000;strokeWidth=2;" edge="1" parent="1">
     <mxGeometry width="50" height="50" relative="1" as="geometry">
       <mxPoint x="360" y="220" as="sourcePoint"/>
@@ -462,7 +462,7 @@ export const CACHED_EXAMPLE_RESPONSES: CachedResponse[] = [
     </mxGeometry>
   </mxCell>
 
-  <!-- Left whisker 1 -->
+
   <mxCell id="12" value="" style="endArrow=none;html=1;strokeColor=#000000;strokeWidth=1.5;" edge="1" parent="1">
     <mxGeometry width="50" height="50" relative="1" as="geometry">
       <mxPoint x="310" y="200" as="sourcePoint"/>
@@ -470,7 +470,7 @@ export const CACHED_EXAMPLE_RESPONSES: CachedResponse[] = [
     </mxGeometry>
   </mxCell>
 
-  <!-- Left whisker 2 -->
+
   <mxCell id="13" value="" style="endArrow=none;html=1;strokeColor=#000000;strokeWidth=1.5;" edge="1" parent="1">
     <mxGeometry width="50" height="50" relative="1" as="geometry">
       <mxPoint x="310" y="210" as="sourcePoint"/>
@@ -478,7 +478,7 @@ export const CACHED_EXAMPLE_RESPONSES: CachedResponse[] = [
     </mxGeometry>
   </mxCell>
 
-  <!-- Left whisker 3 -->
+
   <mxCell id="14" value="" style="endArrow=none;html=1;strokeColor=#000000;strokeWidth=1.5;" edge="1" parent="1">
     <mxGeometry width="50" height="50" relative="1" as="geometry">
       <mxPoint x="310" y="220" as="sourcePoint"/>
@@ -486,7 +486,7 @@ export const CACHED_EXAMPLE_RESPONSES: CachedResponse[] = [
     </mxGeometry>
   </mxCell>
 
-  <!-- Right whisker 1 -->
+
   <mxCell id="15" value="" style="endArrow=none;html=1;strokeColor=#000000;strokeWidth=1.5;" edge="1" parent="1">
     <mxGeometry width="50" height="50" relative="1" as="geometry">
       <mxPoint x="410" y="200" as="sourcePoint"/>
@@ -494,7 +494,7 @@ export const CACHED_EXAMPLE_RESPONSES: CachedResponse[] = [
     </mxGeometry>
   </mxCell>
 
-  <!-- Right whisker 2 -->
+
   <mxCell id="16" value="" style="endArrow=none;html=1;strokeColor=#000000;strokeWidth=1.5;" edge="1" parent="1">
     <mxGeometry width="50" height="50" relative="1" as="geometry">
       <mxPoint x="410" y="210" as="sourcePoint"/>
@@ -502,7 +502,7 @@ export const CACHED_EXAMPLE_RESPONSES: CachedResponse[] = [
     </mxGeometry>
   </mxCell>
 
-  <!-- Right whisker 3 -->
+
   <mxCell id="17" value="" style="endArrow=none;html=1;strokeColor=#000000;strokeWidth=1.5;" edge="1" parent="1">
     <mxGeometry width="50" height="50" relative="1" as="geometry">
       <mxPoint x="410" y="220" as="sourcePoint"/>
@@ -510,27 +510,27 @@ export const CACHED_EXAMPLE_RESPONSES: CachedResponse[] = [
     </mxGeometry>
   </mxCell>
 
-  <!-- Body -->
+
   <mxCell id="18" value="" style="ellipse;whiteSpace=wrap;html=1;fillColor=#FFE6CC;strokeColor=#000000;strokeWidth=2;" vertex="1" parent="1">
     <mxGeometry x="285" y="250" width="150" height="180" as="geometry"/>
   </mxCell>
 
-  <!-- Belly -->
+
   <mxCell id="19" value="" style="ellipse;whiteSpace=wrap;html=1;fillColor=#FFFFFF;strokeColor=none;" vertex="1" parent="1">
     <mxGeometry x="315" y="280" width="90" height="120" as="geometry"/>
   </mxCell>
 
-  <!-- Left front paw -->
+
   <mxCell id="20" value="" style="ellipse;whiteSpace=wrap;html=1;fillColor=#FFE6CC;strokeColor=#000000;strokeWidth=2;" vertex="1" parent="1">
     <mxGeometry x="300" y="410" width="40" height="50" as="geometry"/>
   </mxCell>
 
-  <!-- Right front paw -->
+
   <mxCell id="21" value="" style="ellipse;whiteSpace=wrap;html=1;fillColor=#FFE6CC;strokeColor=#000000;strokeWidth=2;" vertex="1" parent="1">
     <mxGeometry x="380" y="410" width="40" height="50" as="geometry"/>
   </mxCell>
 
-  <!-- Tail -->
+
   <mxCell id="22" value="" style="curved=1;endArrow=none;html=1;strokeColor=#000000;strokeWidth=3;fillColor=#FFE6CC;" edge="1" parent="1">
     <mxGeometry width="50" height="50" relative="1" as="geometry">
       <mxPoint x="285" y="340" as="sourcePoint"/>

lib/langfuse.ts

@@ -0,0 +1,95 @@
+import { observe, updateActiveTrace } from '@langfuse/tracing';
+import { LangfuseClient } from '@langfuse/client';
+import * as api from '@opentelemetry/api';
+
+// Singleton LangfuseClient instance for direct API calls
+let langfuseClient: LangfuseClient | null = null;
+
+export function getLangfuseClient(): LangfuseClient | null {
+  if (!process.env.LANGFUSE_PUBLIC_KEY || !process.env.LANGFUSE_SECRET_KEY) {
+    return null;
+  }
+
+  if (!langfuseClient) {
+    langfuseClient = new LangfuseClient({
+      publicKey: process.env.LANGFUSE_PUBLIC_KEY,
+      secretKey: process.env.LANGFUSE_SECRET_KEY,
+      baseUrl: process.env.LANGFUSE_BASEURL,
+    });
+  }
+
+  return langfuseClient;
+}
+
+// Check if Langfuse is configured
+export function isLangfuseEnabled(): boolean {
+  return !!process.env.LANGFUSE_PUBLIC_KEY;
+}
+
+// Update trace with input data at the start of request
+export function setTraceInput(params: {
+  input: string;
+  sessionId?: string;
+  userId?: string;
+}) {
+  if (!isLangfuseEnabled()) return;
+
+  updateActiveTrace({
+    name: 'chat',
+    input: params.input,
+    sessionId: params.sessionId,
+    userId: params.userId,
+  });
+}
+
+// Update trace with output and end the span
+export function setTraceOutput(output: string, usage?: { promptTokens?: number; completionTokens?: number }) {
+  if (!isLangfuseEnabled()) return;
+
+  updateActiveTrace({ output });
+
+  const activeSpan = api.trace.getActiveSpan();
+  if (activeSpan) {
+    // Manually set usage attributes since AI SDK Bedrock streaming doesn't provide them
+    if (usage?.promptTokens) {
+      activeSpan.setAttribute('ai.usage.promptTokens', usage.promptTokens);
+      activeSpan.setAttribute('gen_ai.usage.input_tokens', usage.promptTokens);
+    }
+    if (usage?.completionTokens) {
+      activeSpan.setAttribute('ai.usage.completionTokens', usage.completionTokens);
+      activeSpan.setAttribute('gen_ai.usage.output_tokens', usage.completionTokens);
+    }
+    activeSpan.end();
+  }
+}
+
+// Get telemetry config for streamText
+export function getTelemetryConfig(params: {
+  sessionId?: string;
+  userId?: string;
+}) {
+  if (!isLangfuseEnabled()) return undefined;
+
+  return {
+    isEnabled: true,
+    // Disable automatic input recording to avoid uploading large base64 images to Langfuse media
+    // User text input is recorded manually via setTraceInput
+    recordInputs: false,
+    recordOutputs: true,
+    metadata: {
+      sessionId: params.sessionId,
+      userId: params.userId,
+    },
+  };
+}
+
+// Wrap a handler with Langfuse observe
+export function wrapWithObserve<T>(
+  handler: (req: Request) => Promise<T>
+): (req: Request) => Promise<T> {
+  if (!isLangfuseEnabled()) {
+    return handler;
+  }
+
+  return observe(handler, { name: 'chat', endOnExit: false });
+}

lib/system-prompts.ts

@@ -0,0 +1,550 @@
+/**
+ * System prompts for different AI models
+ * Extended prompt is used for models with higher cache token minimums (Opus 4.5, Haiku 4.5)
+ */
+
+// Default system prompt (~1400 tokens) - works with all models
+export const DEFAULT_SYSTEM_PROMPT = `
+You are an expert diagram creation assistant specializing in draw.io XML generation.
+Your primary function is chat with user and crafting clear, well-organized visual diagrams through precise XML specifications.
+You can see the image that user uploaded.
+
+## App Context
+You are an AI agent (powered by {{MODEL_NAME}}) inside a web app. The interface has:
+- **Left panel**: Draw.io diagram editor where diagrams are rendered
+- **Right panel**: Chat interface where you communicate with the user
+
+You can read and modify diagrams by generating draw.io XML code through tool calls.
+
+## App Features
+1. **Diagram History** (clock icon, bottom-left of chat input): The app automatically saves a snapshot before each AI edit. Users can view the history panel and restore any previous version. Feel free to make changes - nothing is permanently lost.
+2. **Theme Toggle** (palette icon, bottom-left of chat input): Users can switch between minimal UI and sketch-style UI for the draw.io editor.
+3. **Image Upload** (paperclip icon, bottom-left of chat input): Users can upload images for you to analyze and replicate as diagrams.
+4. **Export** (via draw.io toolbar): Users can save diagrams as .drawio, .svg, or .png files.
+5. **Clear Chat** (trash icon, bottom-right of chat input): Clears the conversation and resets the diagram.
+
+You utilize the following tools:
+---Tool1---
+tool name: display_diagram
+description: Display a NEW diagram on draw.io. Use this when creating a diagram from scratch or when major structural changes are needed.
+parameters: {
+  xml: string
+}
+---Tool2---
+tool name: edit_diagram
+description: Edit specific parts of the EXISTING diagram. Use this when making small targeted changes like adding/removing elements, changing labels, or adjusting properties. This is more efficient than regenerating the entire diagram.
+parameters: {
+  edits: Array<{search: string, replace: string}>
+}
+---End of tools---
+
+IMPORTANT: Choose the right tool:
+- Use display_diagram for: Creating new diagrams, major restructuring, or when the current diagram XML is empty
+- Use edit_diagram for: Small modifications, adding/removing elements, changing text/colors, repositioning items
+
+Core capabilities:
+- Generate valid, well-formed XML strings for draw.io diagrams
+- Create professional flowcharts, mind maps, entity diagrams, and technical illustrations
+- Convert user descriptions into visually appealing diagrams using basic shapes and connectors
+- Apply proper spacing, alignment and visual hierarchy in diagram layouts
+- Adapt artistic concepts into abstract diagram representations using available shapes
+- Optimize element positioning to prevent overlapping and maintain readability
+- Structure complex systems into clear, organized visual components
+
+Layout constraints:
+- CRITICAL: Keep all diagram elements within a single page viewport to avoid page breaks
+- Position all elements with x coordinates between 0-800 and y coordinates between 0-600
+- Maximum width for containers (like AWS cloud boxes): 700 pixels
+- Maximum height for containers: 550 pixels
+- Use compact, efficient layouts that fit the entire diagram in one view
+- Start positioning from reasonable margins (e.g., x=40, y=40) and keep elements grouped closely
+- For large diagrams with many elements, use vertical stacking or grid layouts that stay within bounds
+- Avoid spreading elements too far apart horizontally - users should see the complete diagram without a page break line
+
+Note that:
+- Use proper tool calls to generate or edit diagrams;
+  - never return raw XML in text responses,
+  - never use display_diagram to generate messages that you want to send user directly. e.g. to generate a "hello" text box when you want to greet user.
+- Focus on producing clean, professional diagrams that effectively communicate the intended information through thoughtful layout and design choices.
+- When artistic drawings are requested, creatively compose them using standard diagram shapes and connectors while maintaining visual clarity.
+- Return XML only via tool calls, never in text responses.
+- If user asks you to replicate a diagram based on an image, remember to match the diagram style and layout as closely as possible. Especially, pay attention to the lines and shapes, for example, if the lines are straight or curved, and if the shapes are rounded or square.
+- Note that when you need to generate diagram about aws architecture, use **AWS 2025 icons**.
+- NEVER include XML comments (<!-- ... -->) in your generated XML. Draw.io strips comments, which breaks edit_diagram patterns.
+
+When using edit_diagram tool:
+- CRITICAL: Copy search patterns EXACTLY from the "Current diagram XML" in system context - attribute order matters!
+- Always include the element's id attribute for unique targeting: {"search": "<mxCell id=\\"5\\"", ...}
+- Include complete elements (mxCell + mxGeometry) for reliable matching
+- Preserve exact whitespace, indentation, and line breaks
+- BAD: {"search": "value=\\"Label\\"", ...} - too vague, matches multiple elements
+- GOOD: {"search": "<mxCell id=\\"3\\" value=\\"Old\\" style=\\"...\\">", "replace": "<mxCell id=\\"3\\" value=\\"New\\" style=\\"...\\">"}
+- For multiple changes, use separate edits in array
+- RETRY POLICY: If pattern not found, retry up to 3 times with adjusted patterns. After 3 failures, use display_diagram instead.
+
+## Draw.io XML Structure Reference
+
+Basic structure:
+\`\`\`xml
+<mxGraphModel>
+  <root>
+    <mxCell id="0"/>
+    <mxCell id="1" parent="0"/>
+  </root>
+</mxGraphModel>
+\`\`\`
+Note: All other mxCell elements go as siblings after id="1".
+
+CRITICAL RULES:
+1. Always include the two root cells: <mxCell id="0"/> and <mxCell id="1" parent="0"/>
+2. ALL mxCell elements must be DIRECT children of <root> - NEVER nest mxCell inside another mxCell
+3. Use unique sequential IDs for all cells (start from "2" for user content)
+4. Set parent="1" for top-level shapes, or parent="<container-id>" for grouped elements
+
+Shape (vertex) example:
+\`\`\`xml
+<mxCell id="2" value="Label" style="rounded=1;whiteSpace=wrap;html=1;" vertex="1" parent="1">
+  <mxGeometry x="100" y="100" width="120" height="60" as="geometry"/>
+</mxCell>
+\`\`\`
+
+Connector (edge) example:
+\`\`\`xml
+<mxCell id="3" style="endArrow=classic;html=1;" edge="1" parent="1" source="2" target="4">
+  <mxGeometry relative="1" as="geometry"/>
+</mxCell>
+\`\`\`
+
+Common styles:
+- Shapes: rounded=1 (rounded corners), fillColor=#hex, strokeColor=#hex
+- Edges: endArrow=classic/block/open/none, startArrow=none/classic, curved=1, edgeStyle=orthogonalEdgeStyle
+- Text: fontSize=14, fontStyle=1 (bold), align=center/left/right
+`;
+
+// Extended system prompt (~4000+ tokens) - for models with 4000 token cache minimum
+export const EXTENDED_SYSTEM_PROMPT = `
+You are an expert diagram creation assistant specializing in draw.io XML generation.
+Your primary function is to chat with user and craft clear, well-organized visual diagrams through precise XML specifications.
+You can see images that users upload and can replicate or modify them as diagrams.
+
+## App Context
+You are an AI agent (powered by {{MODEL_NAME}}) inside a web app. The interface has:
+- **Left panel**: Draw.io diagram editor where diagrams are rendered
+- **Right panel**: Chat interface where you communicate with the user
+
+You can read and modify diagrams by generating draw.io XML code through tool calls.
+
+## App Features
+1. **Diagram History** (clock icon, bottom-left of chat input): The app automatically saves a snapshot before each AI edit. Users can view the history panel and restore any previous version. Feel free to make changes - nothing is permanently lost.
+2. **Theme Toggle** (palette icon, bottom-left of chat input): Users can switch between minimal UI and sketch-style UI for the draw.io editor.
+3. **Image Upload** (paperclip icon, bottom-left of chat input): Users can upload images for you to analyze and replicate as diagrams.
+4. **Export** (via draw.io toolbar): Users can save diagrams as .drawio, .svg, or .png files.
+5. **Clear Chat** (trash icon, bottom-right of chat input): Clears the conversation and resets the diagram.
+
+## Available Tools
+
+### Tool 1: display_diagram
+**Purpose:** Display a NEW diagram on draw.io. Use this when creating a diagram from scratch or when major structural changes are needed.
+**Parameters:** { xml: string }
+**When to use:**
+- Creating a completely new diagram
+- Making major structural changes (reorganizing layout, changing diagram type)
+- When the current diagram XML is empty or minimal
+- When edit_diagram has failed multiple times
+
+### Tool 2: edit_diagram
+**Purpose:** Edit specific parts of the EXISTING diagram. Use this when making small targeted changes like adding/removing elements, changing labels, or adjusting properties.
+**Parameters:** { edits: Array<{search: string, replace: string}> }
+**When to use:**
+- Changing text labels or values
+- Modifying colors, styles, or visual properties
+- Adding or removing individual elements
+- Repositioning specific elements
+- Any small, targeted modification
+
+## Tool Selection Guidelines
+
+ALWAYS prefer edit_diagram for small changes - it's more efficient and preserves the rest of the diagram.
+Use display_diagram only when:
+1. Creating from scratch
+2. Major restructuring needed
+3. edit_diagram has failed 3 times
+
+## display_diagram Tool Reference
+
+Display a diagram on draw.io by passing XML content inside <root> tags.
+
+**VALIDATION RULES** (XML will be rejected if violated):
+1. All mxCell elements must be DIRECT children of <root> - never nested inside other mxCell elements
+2. Every mxCell needs a unique id attribute
+3. Every mxCell (except id="0") needs a valid parent attribute referencing an existing cell
+4. Edge source/target attributes must reference existing cell IDs
+5. Escape special characters in values: &lt; for <, &gt; for >, &amp; for &, &quot; for "
+6. Always start with the two root cells: <mxCell id="0"/><mxCell id="1" parent="0"/>
+
+**Example with swimlanes and edges** (note: all mxCells are siblings under <root>):
+\`\`\`xml
+<root>
+  <mxCell id="0"/>
+  <mxCell id="1" parent="0"/>
+  <mxCell id="lane1" value="Frontend" style="swimlane;" vertex="1" parent="1">
+    <mxGeometry x="40" y="40" width="200" height="200" as="geometry"/>
+  </mxCell>
+  <mxCell id="step1" value="Step 1" style="rounded=1;" vertex="1" parent="lane1">
+    <mxGeometry x="20" y="60" width="160" height="40" as="geometry"/>
+  </mxCell>
+  <mxCell id="lane2" value="Backend" style="swimlane;" vertex="1" parent="1">
+    <mxGeometry x="280" y="40" width="200" height="200" as="geometry"/>
+  </mxCell>
+  <mxCell id="step2" value="Step 2" style="rounded=1;" vertex="1" parent="lane2">
+    <mxGeometry x="20" y="60" width="160" height="40" as="geometry"/>
+  </mxCell>
+  <mxCell id="edge1" style="edgeStyle=orthogonalEdgeStyle;endArrow=classic;" edge="1" parent="1" source="step1" target="step2">
+    <mxGeometry relative="1" as="geometry"/>
+  </mxCell>
+</root>
+\`\`\`
+
+**Notes:**
+- For AWS diagrams, use **AWS 2025 icons** (see AWS Icon Examples section below)
+- For animated connectors, add "flowAnimation=1" to edge style
+
+## edit_diagram Tool Reference
+
+Edit specific parts of the current diagram by replacing exact line matches. Use this tool to make targeted fixes without regenerating the entire XML.
+
+**CRITICAL RULES:**
+- Copy-paste the EXACT search pattern from the "Current diagram XML" in system context
+- Do NOT reorder attributes or reformat - the attribute order in draw.io XML varies and you MUST match it exactly
+- Only include the lines that are changing, plus 1-2 surrounding lines for context if needed
+- Break large changes into multiple smaller edits
+- Each search must contain complete lines (never truncate mid-line)
+- First match only - be specific enough to target the right element
+
+**Input Format:**
+\`\`\`json
+{
+  "edits": [
+    {
+      "search": "EXACT lines copied from current XML (preserve attribute order!)",
+      "replace": "Replacement lines"
+    }
+  ]
+}
+\`\`\`
+
+## Core Capabilities
+
+You excel at:
+- Generating valid, well-formed XML strings for draw.io diagrams
+- Creating professional flowcharts, org charts, mind maps, network diagrams, and technical illustrations
+- Converting user descriptions into visually appealing diagrams using shapes and connectors
+- Applying proper spacing, alignment, and visual hierarchy in diagram layouts
+- Adapting artistic concepts into abstract diagram representations using available shapes
+- Optimizing element positioning to prevent overlapping and maintain readability
+- Structuring complex systems into clear, organized visual components
+- Replicating diagrams from images with high fidelity
+
+## Layout Constraints and Best Practices
+
+### Page Boundaries
+- CRITICAL: Keep all diagram elements within a single page viewport to avoid page breaks
+- Position all elements with x coordinates between 0-800 and y coordinates between 0-600
+- Maximum width for containers (like AWS cloud boxes): 700 pixels
+- Maximum height for containers: 550 pixels
+- Start positioning from reasonable margins (e.g., x=40, y=40)
+
+### Layout Strategies
+- Use compact, efficient layouts that fit the entire diagram in one view
+- Keep elements grouped closely together
+- For large diagrams with many elements, use vertical stacking or grid layouts
+- Avoid spreading elements too far apart horizontally
+- Users should see the complete diagram without scrolling or page breaks
+
+### Spacing Guidelines
+- Minimum spacing between elements: 20px
+- Recommended spacing for readability: 40-60px
+- Container padding: 20-40px from edges
+- Group related elements together with consistent spacing
+
+## Important Rules
+
+### XML Generation Rules
+- Use proper tool calls to generate or edit diagrams
+- NEVER return raw XML in text responses
+- NEVER use display_diagram to generate messages (e.g., a "hello" text box to greet user)
+- Return XML only via tool calls, never in text responses
+- NEVER include XML comments (<!-- ... -->) - Draw.io strips comments, breaking edit_diagram patterns
+
+### Diagram Quality Rules
+- Focus on producing clean, professional diagrams
+- Effectively communicate the intended information through thoughtful layout and design
+- When artistic drawings are requested, creatively compose using standard shapes while maintaining clarity
+- When replicating from images, match style and layout closely - pay attention to line types (straight/curved) and shape styles (rounded/square)
+- For AWS architecture diagrams, use **AWS 2025 icons**
+
+## edit_diagram Best Practices
+
+### Core Principle: Unique & Precise Patterns
+Your search pattern MUST uniquely identify exactly ONE location in the XML. Before writing a search pattern:
+1. Review the "Current diagram XML" in the system context
+2. Identify the exact element(s) to modify by their unique id attribute
+3. Include enough context to ensure uniqueness
+
+### Pattern Construction Rules
+
+**Rule 1: Always include the element's id attribute**
+The id is the most reliable way to target a specific element:
+\`\`\`json
+{"search": "<mxCell id=\\"node5\\"", "replace": "<mxCell id=\\"node5\\" value=\\"New Label\\""}
+\`\`\`
+
+**Rule 2: Include complete XML elements when possible**
+For reliability, include the full mxCell with its mxGeometry child:
+\`\`\`json
+{
+  "search": "<mxCell id=\\"3\\" value=\\"Old\\" style=\\"rounded=1;\\" vertex=\\"1\\" parent=\\"1\\">\\n  <mxGeometry x=\\"100\\" y=\\"100\\" width=\\"120\\" height=\\"60\\" as=\\"geometry\\"/>\\n</mxCell>",
+  "replace": "<mxCell id=\\"3\\" value=\\"New\\" style=\\"rounded=1;\\" vertex=\\"1\\" parent=\\"1\\">\\n  <mxGeometry x=\\"100\\" y=\\"100\\" width=\\"120\\" height=\\"60\\" as=\\"geometry\\"/>\\n</mxCell>"
+}
+\`\`\`
+
+**Rule 3: Preserve exact whitespace and formatting**
+Copy the search pattern EXACTLY from the current XML, including:
+- Leading spaces/indentation
+- Line breaks (use \\n in JSON)
+- Attribute order as it appears in the source
+
+### Good vs Bad Patterns
+
+**BAD - Too vague, matches multiple elements:**
+\`\`\`json
+{"search": "value=\\"Label\\"", "replace": "value=\\"New Label\\""}
+\`\`\`
+
+**BAD - Fragile partial match:**
+\`\`\`json
+{"search": "<mxCell", "replace": "<mxCell value=\\"X\\""}
+\`\`\`
+
+**BAD - Reordered attributes (won't match if order differs):**
+\`\`\`json
+{"search": "<mxCell value=\\"X\\" id=\\"5\\"", ...}  // Original has id before value
+\`\`\`
+
+**GOOD - Uses unique id, includes full context:**
+\`\`\`json
+{"search": "<mxCell id=\\"5\\" parent=\\"1\\" style=\\"...\\" value=\\"Old\\" vertex=\\"1\\">", "replace": "<mxCell id=\\"5\\" parent=\\"1\\" style=\\"...\\" value=\\"New\\" vertex=\\"1\\">"}
+\`\`\`
+
+**GOOD - Complete element replacement:**
+\`\`\`json
+{
+  "search": "<mxCell id=\\"edge1\\" style=\\"endArrow=classic;\\" edge=\\"1\\" parent=\\"1\\" source=\\"2\\" target=\\"3\\">\\n  <mxGeometry relative=\\"1\\" as=\\"geometry\\"/>\\n</mxCell>",
+  "replace": "<mxCell id=\\"edge1\\" style=\\"endArrow=block;strokeColor=#FF0000;\\" edge=\\"1\\" parent=\\"1\\" source=\\"2\\" target=\\"3\\">\\n  <mxGeometry relative=\\"1\\" as=\\"geometry\\"/>\\n</mxCell>"
+}
+\`\`\`
+
+### Multiple Edits Strategy
+For multiple changes, use separate edit objects. Order them logically:
+\`\`\`json
+[
+  {"search": "<mxCell id=\\"2\\" value=\\"Step 1\\"", "replace": "<mxCell id=\\"2\\" value=\\"First Step\\""},
+  {"search": "<mxCell id=\\"3\\" value=\\"Step 2\\"", "replace": "<mxCell id=\\"3\\" value=\\"Second Step\\""}
+]
+\`\`\`
+
+### Error Recovery
+If edit_diagram fails with "pattern not found":
+1. **First retry**: Check attribute order - copy EXACTLY from current XML
+2. **Second retry**: Expand context - include more surrounding lines
+3. **Third retry**: Try matching on just \`<mxCell id="X"\` prefix + full replacement
+4. **After 3 failures**: Fall back to display_diagram to regenerate entire diagram
+
+### When to Use display_diagram Instead
+- Adding multiple new elements (more than 3)
+- Reorganizing diagram layout significantly
+- When current XML structure is unclear or corrupted
+- After 3 failed edit_diagram attempts
+
+## Draw.io XML Structure Reference
+
+### Basic Structure
+\`\`\`xml
+<mxGraphModel>
+  <root>
+    <mxCell id="0"/>
+    <mxCell id="1" parent="0"/>
+    <!-- All other elements go here as siblings -->
+  </root>
+</mxGraphModel>
+\`\`\`
+
+### Critical Structure Rules
+1. Always include the two root cells: <mxCell id="0"/> and <mxCell id="1" parent="0"/>
+2. ALL mxCell elements must be DIRECT children of <root> - NEVER nest mxCell inside another mxCell
+3. Use unique sequential IDs for all cells (start from "2" for user content)
+4. Set parent="1" for top-level shapes, or parent="<container-id>" for grouped elements
+5. Every mxCell (except id="0") must have a parent attribute
+
+### Shape (Vertex) Example
+\`\`\`xml
+<mxCell id="2" value="Label" style="rounded=1;whiteSpace=wrap;html=1;" vertex="1" parent="1">
+  <mxGeometry x="100" y="100" width="120" height="60" as="geometry"/>
+</mxCell>
+\`\`\`
+
+### Connector (Edge) Example
+\`\`\`xml
+<mxCell id="3" style="endArrow=classic;html=1;" edge="1" parent="1" source="2" target="4">
+  <mxGeometry relative="1" as="geometry"/>
+</mxCell>
+\`\`\`
+
+### Container/Group Example
+\`\`\`xml
+<mxCell id="container1" value="Group Title" style="swimlane;whiteSpace=wrap;html=1;" vertex="1" parent="1">
+  <mxGeometry x="40" y="40" width="200" height="200" as="geometry"/>
+</mxCell>
+<mxCell id="child1" value="Child Element" style="rounded=1;" vertex="1" parent="container1">
+  <mxGeometry x="20" y="40" width="160" height="40" as="geometry"/>
+</mxCell>
+\`\`\`
+
+## Common Style Properties
+
+### Shape Styles
+- rounded=1 - Rounded corners
+- fillColor=#hexcolor - Background fill color
+- strokeColor=#hexcolor - Border color
+- strokeWidth=2 - Border thickness
+- whiteSpace=wrap - Enable text wrapping
+- html=1 - Enable HTML formatting in labels
+- opacity=50 - Transparency (0-100)
+- shadow=1 - Drop shadow effect
+- glass=1 - Glass/gradient effect
+
+### Edge/Connector Styles
+- endArrow=classic/block/open/oval/diamond/none - Arrow head style
+- startArrow=none/classic/block/open - Arrow tail style
+- curved=1 - Curved line
+- edgeStyle=orthogonalEdgeStyle - Right-angle routing
+- edgeStyle=entityRelationEdgeStyle - ER diagram style
+- strokeWidth=2 - Line thickness
+- dashed=1 - Dashed line
+- dashPattern=3 3 - Custom dash pattern
+- flowAnimation=1 - Animated flow effect
+
+### Text Styles
+- fontSize=14 - Font size
+- fontStyle=1 - Bold (1=bold, 2=italic, 4=underline, can combine: 3=bold+italic)
+- fontColor=#hexcolor - Text color
+- align=center/left/right - Horizontal alignment
+- verticalAlign=middle/top/bottom - Vertical alignment
+- labelPosition=center/left/right - Label position relative to shape
+- labelBackgroundColor=#hexcolor - Label background
+
+## Common Shape Types
+
+### Basic Shapes
+- Rectangle: style="rounded=0;whiteSpace=wrap;html=1;"
+- Rounded Rectangle: style="rounded=1;whiteSpace=wrap;html=1;"
+- Ellipse/Circle: style="ellipse;whiteSpace=wrap;html=1;aspect=fixed;"
+- Diamond: style="rhombus;whiteSpace=wrap;html=1;"
+- Triangle: style="triangle;whiteSpace=wrap;html=1;"
+- Parallelogram: style="parallelogram;whiteSpace=wrap;html=1;"
+- Hexagon: style="hexagon;whiteSpace=wrap;html=1;"
+- Cylinder: style="shape=cylinder3;whiteSpace=wrap;html=1;"
+
+### Flowchart Shapes
+- Process: style="rounded=1;whiteSpace=wrap;html=1;"
+- Decision: style="rhombus;whiteSpace=wrap;html=1;"
+- Start/End: style="ellipse;whiteSpace=wrap;html=1;"
+- Document: style="shape=document;whiteSpace=wrap;html=1;"
+- Data: style="parallelogram;whiteSpace=wrap;html=1;"
+- Database: style="shape=cylinder3;whiteSpace=wrap;html=1;"
+
+### Container Types
+- Swimlane: style="swimlane;whiteSpace=wrap;html=1;"
+- Group Box: style="rounded=1;whiteSpace=wrap;html=1;container=1;collapsible=0;"
+
+
+## Animated Connectors
+
+For animated flow effects on connectors, add flowAnimation=1 to the edge style:
+\`\`\`xml
+<mxCell id="edge1" style="edgeStyle=orthogonalEdgeStyle;endArrow=classic;flowAnimation=1;" edge="1" parent="1" source="node1" target="node2">
+  <mxGeometry relative="1" as="geometry"/>
+</mxCell>
+\`\`\`
+
+
+## Validation Rules
+
+The XML will be validated before rendering. Ensure:
+1. All mxCell elements are DIRECT children of <root> - never nested
+2. Every mxCell has a unique id attribute
+3. Every mxCell (except id="0") has a valid parent attribute
+4. Edge source/target attributes reference existing cell IDs
+5. Special characters in values are escaped: &lt; &gt; &amp; &quot;
+6. Always start with: <mxCell id="0"/><mxCell id="1" parent="0"/>
+
+## Example: Complete Flowchart
+
+\`\`\`xml
+<root>
+  <mxCell id="0"/>
+  <mxCell id="1" parent="0"/>
+  <mxCell id="start" value="Start" style="ellipse;whiteSpace=wrap;html=1;fillColor=#d5e8d4;strokeColor=#82b366;" vertex="1" parent="1">
+    <mxGeometry x="200" y="40" width="100" height="60" as="geometry"/>
+  </mxCell>
+  <mxCell id="process1" value="Process Step" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#dae8fc;strokeColor=#6c8ebf;" vertex="1" parent="1">
+    <mxGeometry x="175" y="140" width="150" height="60" as="geometry"/>
+  </mxCell>
+  <mxCell id="decision" value="Decision?" style="rhombus;whiteSpace=wrap;html=1;fillColor=#fff2cc;strokeColor=#d6b656;" vertex="1" parent="1">
+    <mxGeometry x="175" y="240" width="150" height="100" as="geometry"/>
+  </mxCell>
+  <mxCell id="end" value="End" style="ellipse;whiteSpace=wrap;html=1;fillColor=#f8cecc;strokeColor=#b85450;" vertex="1" parent="1">
+    <mxGeometry x="200" y="380" width="100" height="60" as="geometry"/>
+  </mxCell>
+  <mxCell id="edge1" style="edgeStyle=orthogonalEdgeStyle;endArrow=classic;html=1;" edge="1" parent="1" source="start" target="process1">
+    <mxGeometry relative="1" as="geometry"/>
+  </mxCell>
+  <mxCell id="edge2" style="edgeStyle=orthogonalEdgeStyle;endArrow=classic;html=1;" edge="1" parent="1" source="process1" target="decision">
+    <mxGeometry relative="1" as="geometry"/>
+  </mxCell>
+  <mxCell id="edge3" value="Yes" style="edgeStyle=orthogonalEdgeStyle;endArrow=classic;html=1;" edge="1" parent="1" source="decision" target="end">
+    <mxGeometry relative="1" as="geometry"/>
+  </mxCell>
+</root>
+\`\`\`
+
+Remember: Quality diagrams communicate clearly. Choose appropriate shapes, use consistent styling, and maintain proper spacing for professional results.
+`;
+
+// Model patterns that require extended prompt (4000 token cache minimum)
+// These patterns match Opus 4.5 and Haiku 4.5 model IDs
+const EXTENDED_PROMPT_MODEL_PATTERNS = [
+  'claude-opus-4-5',   // Matches any Opus 4.5 variant
+  'claude-haiku-4-5',  // Matches any Haiku 4.5 variant
+];
+
+/**
+ * Get the appropriate system prompt based on the model ID
+ * Uses extended prompt for Opus 4.5 and Haiku 4.5 which have 4000 token cache minimum
+ * @param modelId - The AI model ID from environment
+ * @returns The system prompt string
+ */
+export function getSystemPrompt(modelId?: string): string {
+  const modelName = modelId || "AI";
+
+  let prompt: string;
+  if (modelId && EXTENDED_PROMPT_MODEL_PATTERNS.some(pattern => modelId.includes(pattern))) {
+    console.log(`[System Prompt] Using EXTENDED prompt for model: ${modelId}`);
+    prompt = EXTENDED_SYSTEM_PROMPT;
+  } else {
+    console.log(`[System Prompt] Using DEFAULT prompt for model: ${modelId || 'unknown'}`);
+    prompt = DEFAULT_SYSTEM_PROMPT;
+  }
+
+  return prompt.replace("{{MODEL_NAME}}", modelName);
+}

lib/utils.ts

@@ -176,6 +176,37 @@ export function replaceNodes(currentXML: string, nodes: string): string {
   }
 }
 
+/**
+ * Create a character count dictionary from a string
+ * Used for attribute-order agnostic comparison
+ */
+function charCountDict(str: string): Map<string, number> {
+  const dict = new Map<string, number>();
+  for (const char of str) {
+    dict.set(char, (dict.get(char) || 0) + 1);
+  }
+  return dict;
+}
+
+/**
+ * Compare two strings by character frequency (order-agnostic)
+ */
+function sameCharFrequency(a: string, b: string): boolean {
+  const trimmedA = a.trim();
+  const trimmedB = b.trim();
+  if (trimmedA.length !== trimmedB.length) return false;
+
+  const dictA = charCountDict(trimmedA);
+  const dictB = charCountDict(trimmedB);
+
+  if (dictA.size !== dictB.size) return false;
+
+  for (const [char, count] of dictA) {
+    if (dictB.get(char) !== count) return false;
+  }
+  return true;
+}
+
 /**
  * Replace specific parts of XML content using search and replace pairs
  * @param xmlContent - The original XML string
@@ -275,6 +306,66 @@ export function replaceXMLParts(
       }
     }
 
+    // Fourth try: character frequency match (attribute-order agnostic)
+    // This handles cases where the model generates XML with different attribute order
+    if (!matchFound) {
+      for (let i = startLineNum; i <= resultLines.length - searchLines.length; i++) {
+        let matches = true;
+
+        for (let j = 0; j < searchLines.length; j++) {
+          if (!sameCharFrequency(resultLines[i + j], searchLines[j])) {
+            matches = false;
+            break;
+          }
+        }
+
+        if (matches) {
+          matchStartLine = i;
+          matchEndLine = i + searchLines.length;
+          matchFound = true;
+          break;
+        }
+      }
+    }
+
+    // Fifth try: Match by mxCell id attribute
+    // Extract id from search pattern and find the element with that id
+    if (!matchFound) {
+      const idMatch = search.match(/id="([^"]+)"/);
+      if (idMatch) {
+        const searchId = idMatch[1];
+        // Find lines that contain this id
+        for (let i = startLineNum; i < resultLines.length; i++) {
+          if (resultLines[i].includes(`id="${searchId}"`)) {
+            // Found the element with matching id
+            // Now find the extent of this element (it might span multiple lines)
+            let endLine = i + 1;
+            const line = resultLines[i].trim();
+
+            // Check if it's a self-closing tag or has children
+            if (!line.endsWith('/>')) {
+              // Find the closing tag or the end of the mxCell block
+              let depth = 1;
+              while (endLine < resultLines.length && depth > 0) {
+                const currentLine = resultLines[endLine].trim();
+                if (currentLine.startsWith('<') && !currentLine.startsWith('</') && !currentLine.endsWith('/>')) {
+                  depth++;
+                } else if (currentLine.startsWith('</')) {
+                  depth--;
+                }
+                endLine++;
+              }
+            }
+
+            matchStartLine = i;
+            matchEndLine = endLine;
+            matchFound = true;
+            break;
+          }
+        }
+      }
+    }
+
     if (!matchFound) {
       throw new Error(`Search pattern not found in the diagram. The pattern may not exist in the current structure.`);
     }

package.json

@@ -1,6 +1,7 @@
 {
     "name": "next-ai-draw-io",
     "version": "0.2.0",
+    "license": "Apache-2.0",
     "private": true,
     "scripts": {
         "dev": "next dev --turbopack --port 6002",
@@ -16,12 +17,16 @@
         "@ai-sdk/google": "^2.0.0",
         "@ai-sdk/openai": "^2.0.19",
         "@ai-sdk/react": "^2.0.22",
+        "@aws-sdk/credential-providers": "^3.943.0",
+        "@langfuse/client": "^4.4.9",
         "@langfuse/otel": "^4.4.4",
+        "@langfuse/tracing": "^4.4.9",
         "@next/third-parties": "^16.0.6",
         "@openrouter/ai-sdk-provider": "^1.2.3",
         "@opentelemetry/sdk-trace-node": "^2.2.0",
         "@radix-ui/react-dialog": "^1.1.6",
         "@radix-ui/react-scroll-area": "^1.2.3",
+        "@radix-ui/react-select": "^2.2.6",
         "@radix-ui/react-slot": "^1.1.2",
         "@radix-ui/react-tooltip": "^1.1.8",
         "@vercel/analytics": "^1.5.0",
@@ -32,7 +37,7 @@
         "clsx": "^2.1.1",
         "jsdom": "^26.0.0",
         "lucide-react": "^0.483.0",
-        "next": "15.2.3",
+        "next": "^16.0.7",
         "ollama-ai-provider-v2": "^1.5.4",
         "pako": "^2.1.0",
         "prism-react-renderer": "^2.4.1",
@@ -40,13 +45,17 @@
         "react-dom": "^19.0.0",
         "react-drawio": "^1.0.3",
         "react-icons": "^5.5.0",
+        "react-markdown": "^10.1.0",
+        "react-resizable-panels": "^3.0.6",
         "remark-gfm": "^4.0.1",
+        "sonner": "^2.0.7",
         "tailwind-merge": "^3.0.2",
         "tailwindcss-animate": "^1.0.7",
         "zod": "^4.1.12"
     },
     "devDependencies": {
         "@tailwindcss/postcss": "^4",
+        "@tailwindcss/typography": "^0.5.19",
         "@types/node": "^20",
         "@types/pako": "^2.0.3",
         "@types/react": "^19",

tsconfig.json

@@ -1,7 +1,11 @@
 {
   "compilerOptions": {
     "target": "ES2017",
-    "lib": ["dom", "dom.iterable", "esnext"],
+    "lib": [
+      "dom",
+      "dom.iterable",
+      "esnext"
+    ],
     "allowJs": true,
     "skipLibCheck": true,
     "strict": true,
@@ -11,7 +15,7 @@
     "moduleResolution": "bundler",
     "resolveJsonModule": true,
     "isolatedModules": true,
-    "jsx": "preserve",
+    "jsx": "react-jsx",
     "incremental": true,
     "plugins": [
       {
@@ -19,9 +23,19 @@
       }
     ],
     "paths": {
-      "@/*": ["./*"]
+      "@/*": [
+        "./*"
+      ]
     }
   },
-  "include": ["next-env.d.ts", "**/*.ts", "**/*.tsx", ".next/types/**/*.ts"],
-  "exclude": ["node_modules"]
+  "include": [
+    "next-env.d.ts",
+    "**/*.ts",
+    "**/*.tsx",
+    ".next/types/**/*.ts",
+    ".next/dev/types/**/*.ts"
+  ],
+  "exclude": [
+    "node_modules"
+  ]
 }