AI-First Starting UX: Build with AI path

assets/js/collaborative-editor/CollaborativeEditor.tsx

@@ -183,16 +183,19 @@ function LandingScreenWrapper({
   aiAssistantEnabled: boolean;
 }) {
   const showLandingScreen = useShowLandingScreen();
-  const { openYAMLImportModal } = useUICommands();
+  const { openYAMLImportModal, dismissLandingScreen, openAIAssistantPanel } =
+    useUICommands();
 
   if (!showLandingScreen) return null;
 
   return (
     <>
-      {/* TODO-AI-FIRST Stubs — wired up in Issues #4857 (Build with AI), #4858 (Browse Templates) */}
       <LandingScreen
         aiAssistantEnabled={aiAssistantEnabled}
-        onBuildWithAI={() => {}}
+        onBuildWithAI={(prompt: string) => {
+          dismissLandingScreen();
+          openAIAssistantPanel(prompt);
+        }}
         onBuildFromScratch={() => {}}
         onBrowseTemplates={() => {}}
         onImportYAML={openYAMLImportModal}

assets/js/collaborative-editor/components/AIAssistantPanel.tsx

@@ -2,6 +2,7 @@ import { useEffect, useState, useRef } from 'react';
 
 import { cn } from '#/utils/cn';
 
+import { Tooltip } from '../../components/Tooltip';
 import {
   useAIStorageKey,
   useAISessionType,
@@ -15,11 +16,10 @@ import { useSelectedStepId, useSelectedRunId } from '../hooks/useHistory';
 import { ChatInput } from './ChatInput';
 import { DisclaimerScreen } from './DisclaimerScreen';
 import { SessionList } from './SessionList';
-import { Tooltip } from '../../components/Tooltip';
 
 interface AIAssistantPanelProps {
   isOpen: boolean;
-  onClose: () => void;
+  onClose?: () => void;
   onNewConversation?: () => void;
   onSessionSelect?: (sessionId: string) => void;
   onShowSessions?: () => void;
@@ -233,7 +233,7 @@ export function AIAssistantPanel({
       if (onShowSessions) {
         onShowSessions();
       }
-    } else {
+    } else if (onClose) {
       onClose();
     }
   };
@@ -390,27 +390,31 @@ export function AIAssistantPanel({
                 </div>
               )}
             </div>
-            <Tooltip
-              content={sessionId ? 'Close current session' : 'Close assistant'}
-            >
-              <button
-                type="button"
-                onClick={handleClose}
-                className={cn(
-                  'inline-flex items-center justify-center',
-                  'h-8 w-8 rounded-md',
-                  'text-gray-400 hover:text-gray-600 hover:bg-gray-100',
-                  'focus:outline-none focus:ring-2 focus:ring-offset-2 focus:ring-primary-500',
-                  'transition-all duration-150',
-                  'flex-shrink-0'
-                )}
-                aria-label={
+            {onClose && (
+              <Tooltip
+                content={
                   sessionId ? 'Close current session' : 'Close assistant'
                 }
               >
-                <span className="hero-x-mark h-5 w-5" />
-              </button>
-            </Tooltip>
+                <button
+                  type="button"
+                  onClick={handleClose}
+                  className={cn(
+                    'inline-flex items-center justify-center',
+                    'h-8 w-8 rounded-md',
+                    'text-gray-400 hover:text-gray-600 hover:bg-gray-100',
+                    'focus:outline-none focus:ring-2 focus:ring-offset-2 focus:ring-primary-500',
+                    'transition-all duration-150',
+                    'shrink-0'
+                  )}
+                  aria-label={
+                    sessionId ? 'Close current session' : 'Close assistant'
+                  }
+                >
+                  <span className="hero-x-mark h-5 w-5" />
+                </button>
+              </Tooltip>
+            )}
           </div>
         </div>
       </div>

assets/js/collaborative-editor/components/AIAssistantPanelWrapper.tsx

@@ -61,7 +61,7 @@ import {
   useWorkflowState,
 } from '../hooks/useWorkflow';
 import { useKeyboardShortcut } from '../keyboard';
-import type { JobCodeContext } from '../types/ai-assistant';
+import type { JobCodeContext, Message } from '../types/ai-assistant';
 import { Z_INDEX } from '../utils/constants';
 import {
   prepareWorkflowForSerialization,
@@ -103,6 +103,9 @@ export function AIAssistantPanelWrapper({
   const isPinnedVersion =
     currentVersion !== undefined && currentVersion !== null;
 
+  const { isReadOnly } = useWorkflowReadOnly();
+  const isNewWorkflow = useIsNewWorkflow();
+
   // Track IDE state changes to re-focus chat input when IDE closes
   const isIDEOpen = params.panel === 'editor';
   const [focusTrigger, setFocusTrigger] = useState(0);
@@ -128,7 +131,7 @@ export function AIAssistantPanelWrapper({
       toggleAIAssistantPanel();
     },
     0,
-    { enabled: !isPinnedVersion && aiAssistantEnabled }
+    { enabled: !isPinnedVersion && aiAssistantEnabled && !isNewWorkflow }
   );
 
   const aiStore = useAIStore();
@@ -157,10 +160,7 @@ export function AIAssistantPanelWrapper({
   const workflow = useWorkflowState(state => state.workflow);
   const limits = useLimits();
 
-  // Check readonly state and new workflow status
   // AI can apply changes if: not readonly OR is a new workflow (being created)
-  const { isReadOnly } = useWorkflowReadOnly();
-  const isNewWorkflow = useIsNewWorkflow();
   const canApplyChanges = !isReadOnly || isNewWorkflow;
   const isWriteDisabled = !canApplyChanges;
 
@@ -548,6 +548,7 @@ export function AIAssistantPanelWrapper({
     startApplyingJobCode,
     doneApplyingJobCode,
     updateJob,
+    saveWorkflow,
   } = useWorkflowActions();
 
   // Get applying state from workflow store for disabling Apply button across all users
@@ -559,6 +560,24 @@ export function AIAssistantPanelWrapper({
     state => state.applyingJobCodeMessageId
   );
 
+  const onValidationError = useCallback(
+    (errorMessage: string) => {
+      const message: Message = {
+        id: crypto.randomUUID(),
+        role: 'assistant',
+        content: errorMessage,
+        status: 'error',
+        inserted_at: new Date().toISOString(),
+      };
+      aiStore._addMessage(message);
+    },
+    [aiStore]
+  );
+
+  // Track whether we applied via streaming so the auto-apply effect in the
+  // hook can skip the duplicate when the final new_message arrives
+  const appliedViaStreamingRef = useRef(false);
+
   // Hook to handle workflow/job code application logic
   const { handleApplyWorkflow, handlePreviewJobCode, handleApplyJobCode } =
     useAIWorkflowApplications({
@@ -573,13 +592,16 @@ export function AIAssistantPanelWrapper({
           : null,
       currentUserId: user?.id,
       aiMode,
+      isNewWorkflow,
+      onValidationError,
       workflowActions: {
         importWorkflow,
         startApplyingWorkflow,
         doneApplyingWorkflow,
         startApplyingJobCode,
         doneApplyingJobCode,
         updateJob,
+        saveWorkflow,
       },
       monacoRef,
       jobs,
@@ -589,6 +611,7 @@ export function AIAssistantPanelWrapper({
       previewingMessageId,
       setApplyingMessageId,
       appliedMessageIdsRef,
+      appliedViaStreamingRef,
     });
 
   // Auto-preview job code when AI responds with code
@@ -608,9 +631,6 @@ export function AIAssistantPanelWrapper({
   const appliedStreamingChangesRef = useRef<Record<string, unknown> | null>(
     null
   );
-  // Track whether we applied via streaming so we can skip the duplicate
-  // auto-apply when the final new_message arrives
-  const appliedViaStreamingRef = useRef(false);
   useEffect(() => {
     if (!streamingChanges || !canApplyChanges) return;
     // Avoid re-applying the same streaming changes object
@@ -626,7 +646,6 @@ export function AIAssistantPanelWrapper({
     } else if (aiMode?.page === 'job_code' && 'code' in streamingChanges) {
       const code = streamingChanges['code'] as string;
       if (code) {
-        appliedViaStreamingRef.current = true;
         handlePreviewJobCode(code, '__streaming__');
       }
     }
@@ -638,22 +657,6 @@ export function AIAssistantPanelWrapper({
     handlePreviewJobCode,
   ]);
 
-  // When a new assistant message with code arrives after we already applied
-  // via streaming, mark it as already applied to prevent duplicate auto-apply
-  // and update previewingMessageId to the real ID to prevent diff flicker
-  useEffect(() => {
-    if (!appliedViaStreamingRef.current) return;
-
-    const latestAssistantMessage = [...messages]
-      .reverse()
-      .find(m => m.role === 'assistant' && m.code && m.status === 'success');
-
-    if (latestAssistantMessage) {
-      appliedMessageIdsRef.current.add(latestAssistantMessage.id);
-      appliedViaStreamingRef.current = false;
-    }
-  }, [messages, appliedMessageIdsRef]);
-
   return (
     <div
       className="flex h-full flex-shrink-0"
@@ -683,7 +686,7 @@ export function AIAssistantPanelWrapper({
           <div className="flex-1 overflow-hidden">
             <AIAssistantPanel
               isOpen={isAIAssistantPanelOpen}
-              onClose={handleClosePanel}
+              onClose={isNewWorkflow ? undefined : handleClosePanel}
               onNewConversation={handleNewConversation}
               onSessionSelect={handleSessionSelect}
               onShowSessions={handleShowSessions}

assets/js/collaborative-editor/components/MessageList.tsx

@@ -545,18 +545,34 @@ export function MessageList({
                 }
               >
                 <div className="space-y-3">
-                  <MarkdownContent
-                    content={
-                      isStreaming(message)
-                        ? message.content.replace(/\n+$/, '')
-                        : message.content
-                    }
-                    showAddButtons={
-                      !isStreaming(message) && showAddButtons && !message.code
-                    }
-                    isWriteDisabled={isWriteDisabled}
-                    className={PROSE_CLASSES}
-                  />
+                  {message.status === 'error' &&
+                  !isStreaming(message) &&
+                  message.content.trim() ? (
+                    <div
+                      className="rounded-lg border border-red-200 bg-red-50 px-3 py-2"
+                      data-testid="ai-validation-error"
+                    >
+                      <div className="flex items-start gap-2">
+                        <span className="hero-exclamation-circle h-4 w-4 text-red-600 flex-shrink-0 mt-0.5" />
+                        <p className="text-sm text-red-700 leading-relaxed">
+                          {message.content}
+                        </p>
+                      </div>
+                    </div>
+                  ) : (
+                    <MarkdownContent
+                      content={
+                        isStreaming(message)
+                          ? message.content.replace(/\n+$/, '')
+                          : message.content
+                      }
+                      showAddButtons={
+                        !isStreaming(message) && showAddButtons && !message.code
+                      }
+                      isWriteDisabled={isWriteDisabled}
+                      className={PROSE_CLASSES}
+                    />
+                  )}
 
                   {/* Status (e.g. "Generating code...") Apollo may stream
                       after the text answer, while we wait for code. Same
@@ -645,33 +661,35 @@ export function MessageList({
                     </div>
                   )}
 
-                  {!isStreaming(message) && message.status === 'error' && (
-                    <div
-                      className="flex items-center gap-2 px-3 py-2 rounded-lg bg-red-50 border border-red-200"
-                      data-testid="ai-error-message"
-                    >
-                      <span className="hero-exclamation-circle h-4 w-4 text-red-600 flex-shrink-0" />
-                      <span className="text-sm text-red-700 flex-1">
-                        Failed to send message. Please try again.
-                      </span>
-                      {onRetryMessage && (
-                        <button
-                          type="button"
-                          onClick={() => onRetryMessage(message.id)}
-                          className={cn(
-                            'inline-flex items-center gap-1.5 px-3 py-1.5',
-                            'text-xs font-medium rounded-md',
-                            'bg-red-100 text-red-700 hover:bg-red-200',
-                            'transition-colors duration-150',
-                            'focus:outline-none focus:ring-2 focus:ring-red-500 focus:ring-offset-1'
-                          )}
-                        >
-                          <span className="hero-arrow-path h-3.5 w-3.5" />
-                          Retry
-                        </button>
-                      )}
-                    </div>
-                  )}
+                  {!isStreaming(message) &&
+                    message.status === 'error' &&
+                    !message.content.trim() && (
+                      <div
+                        className="flex items-center gap-2 px-3 py-2 rounded-lg bg-red-50 border border-red-200"
+                        data-testid="ai-error-message"
+                      >
+                        <span className="hero-exclamation-circle h-4 w-4 text-red-600 flex-shrink-0" />
+                        <span className="text-sm text-red-700 flex-1">
+                          Failed to send message. Please try again.
+                        </span>
+                        {onRetryMessage && (
+                          <button
+                            type="button"
+                            onClick={() => onRetryMessage(message.id)}
+                            className={cn(
+                              'inline-flex items-center gap-1.5 px-3 py-1.5',
+                              'text-xs font-medium rounded-md',
+                              'bg-red-100 text-red-700 hover:bg-red-200',
+                              'transition-colors duration-150',
+                              'focus:outline-none focus:ring-2 focus:ring-red-500 focus:ring-offset-1'
+                            )}
+                          >
+                            <span className="hero-arrow-path h-3.5 w-3.5" />
+                            Retry
+                          </button>
+                        )}
+                      </div>
+                    )}
 
                   {!isStreaming(message) && message.status === 'processing' && (
                     <div className="flex items-center gap-2 text-gray-600">

assets/js/collaborative-editor/components/WorkflowEditor.tsx

@@ -505,6 +505,7 @@ export function WorkflowEditor({
         {/* Show placeholder when workflow is empty and landing screen is not covering it */}
         {isNewWorkflow &&
           !showLandingScreen &&
+          !isAIAssistantPanelOpen &&
           workflow.jobs.length === 0 &&
           workflow.triggers.length === 0 && (
             <div className="absolute inset-0 flex items-center justify-center pointer-events-none">