fix: remove "Let AI Decide" option from KB Accelerator upload

The uploader should know their content type — auto-detection adds
complexity and currently just defaults to troubleshooting anyway.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend/app/api/endpoints/kb_accelerator.py

@@ -288,11 +288,11 @@ async def upload_kb_article(
     else:
         raise HTTPException(status_code=400, detail="Provide either a file or content text.")
 
-    # Validate target_type
-    if target_type and target_type not in ("troubleshooting", "procedural"):
-        raise HTTPException(status_code=400, detail="target_type must be 'troubleshooting' or 'procedural'.")
+    # Validate target_type (required — frontend must specify)
     if not target_type:
-        target_type = "troubleshooting"  # Default; Phase 2 adds "let AI decide"
+        target_type = "troubleshooting"
+    if target_type not in ("troubleshooting", "procedural"):
+        raise HTTPException(status_code=400, detail="target_type must be 'troubleshooting' or 'procedural'.")
 
     # Create KB import record
     kb_import = KBImport(

frontend/src/components/kb-accelerator/UploadScreen.tsx

@@ -5,7 +5,7 @@ import { Textarea } from '@/components/ui/Textarea'
 import { Input } from '@/components/ui/Input'
 import type { KBQuotaResponse } from '@/types/kbAccelerator'
 
-type TargetType = 'troubleshooting' | 'procedural' | 'auto'
+type TargetType = 'troubleshooting' | 'procedural'
 
 interface UploadScreenProps {
   quota: KBQuotaResponse | null
@@ -25,11 +25,6 @@ const TARGET_TYPES = [
     label: 'Project Flow',
     description: 'Step-by-step procedure with warnings and variables',
   },
-  {
-    value: 'auto' as const,
-    label: 'Let AI Decide',
-    description: 'AI will determine the best flow type from your content',
-  },
 ]
 
 const FORMAT_LABELS: Record<string, string> = {
@@ -45,7 +40,7 @@ export function UploadScreen({ quota, onSubmitText, onSubmitFile, loading }: Upl
   const [mode, setMode] = useState<'paste' | 'file'>('paste')
   const [content, setContent] = useState('')
   const [title, setTitle] = useState('')
-  const [targetType, setTargetType] = useState<TargetType>('auto')
+  const [targetType, setTargetType] = useState<TargetType>('troubleshooting')
   const [file, setFile] = useState<File | null>(null)
   const [dragOver, setDragOver] = useState(false)
   const fileInputRef = useRef<HTMLInputElement>(null)
@@ -231,7 +226,7 @@ export function UploadScreen({ quota, onSubmitText, onSubmitFile, loading }: Upl
         <p className="font-label text-[0.625rem] uppercase tracking-[0.1em] text-muted-foreground mb-2">
           Target Flow Type
         </p>
-        <div className="grid grid-cols-1 sm:grid-cols-3 gap-3">
+        <div className="grid grid-cols-1 sm:grid-cols-2 gap-3">
           {TARGET_TYPES.map(t => (
             <button
               key={t.value}

frontend/src/pages/KBAcceleratorPage.tsx

@@ -10,7 +10,7 @@ import { getTreeEditorPath } from '@/lib/routing'
 import type { KBImport, KBQuotaResponse, KBCommitResponse, KBNodeEditRequest } from '@/types/kbAccelerator'
 
 type Phase = 'upload' | 'processing' | 'review' | 'success'
-type TargetType = 'troubleshooting' | 'procedural' | 'auto'
+type TargetType = 'troubleshooting' | 'procedural'
 
 export default function KBAcceleratorPage() {
   const navigate = useNavigate()
@@ -61,7 +61,7 @@ export default function KBAcceleratorPage() {
       const resp = await kbAcceleratorApi.uploadText({
         content,
         title: title || undefined,
-        target_type: targetType === 'auto' ? undefined : targetType,
+        target_type: targetType,
       })
       setImportId(resp.id)
       setPhase('processing')
@@ -77,7 +77,7 @@ export default function KBAcceleratorPage() {
   const handleSubmitFile = async (file: File, targetType: TargetType) => {
     setLoading(true)
     try {
-      const resp = await kbAcceleratorApi.uploadFile(file, targetType === 'auto' ? undefined : targetType)
+      const resp = await kbAcceleratorApi.uploadFile(file, targetType)
       setImportId(resp.id)
       setPhase('processing')
       startPolling(resp.id)