Surface YOLO preflight in Detection Lab

frontend/README.md

@@ -120,6 +120,7 @@ AI Lab run controls explicitly explain when no raster dataset is available, inst
 ## Sprint 8B additions
 - Detection Lab now exposes the `yolo-configured` capability reported by the backend.
 - When `yolo-configured` is selected, users can provide an existing raster tile manifest path.
+- Detection Lab includes a read-only YOLO runtime preflight panel with backend status, dependency visibility, local model configuration, `torch`/`ultralytics` versions, CUDA state and `YOLO_CONFIG_DIR`.
 - The UI still does not download models or create fake detections; backend status and error codes remain the source of truth.
 
 ## Sprint 8C additions

frontend/src/App.tsx

@@ -242,7 +242,11 @@ function App(): JSX.Element {
     detectionQaResult,
     detectionQaError,
     runningDetectionQa,
+    yoloPreflight,
+    loadingYoloPreflight,
+    yoloPreflightError,
     loadDetectionModels,
+    loadYoloPreflight,
     loadDetectionRuns,
     loadDetectionResults,
     runDetection,
@@ -945,10 +949,14 @@ function App(): JSX.Element {
                 detectionQaResult={detectionQaResult}
                 detectionQaError={detectionQaError}
                 runningDetectionQa={runningDetectionQa}
+                yoloPreflight={yoloPreflight}
+                loadingYoloPreflight={loadingYoloPreflight}
+                yoloPreflightError={yoloPreflightError}
                 selectedProjectId={selectedProjectId}
                 rasterDatasets={rasterDatasets}
                 referenceDatasets={referenceDatasets}
                 onLoadModels={loadDetectionModels}
+                onRefreshYoloPreflight={() => loadYoloPreflight()}
                 onSelectDataset={setSelectedDetectionDatasetId}
                 onSelectModel={setSelectedDetectionModelId}
                 onSetConfidenceThreshold={setDetectionConfidenceThreshold}

frontend/src/components/detection/DetectionLab.tsx

@@ -5,6 +5,7 @@ import type {
   DetectionRead,
   DetectionRunRead,
   DetectionRunResponse,
+  YoloPreflightResponse,
 } from '../../types'
 
 interface DetectionLabProps {
@@ -28,10 +29,14 @@ interface DetectionLabProps {
   detectionQaResult: DetectionQaResult | null
   detectionQaError: string | null
   runningDetectionQa: boolean
+  yoloPreflight: YoloPreflightResponse | null
+  loadingYoloPreflight: boolean
+  yoloPreflightError: string | null
   selectedProjectId: string | null
   rasterDatasets: DatasetCreateResponse[]
   referenceDatasets: DatasetCreateResponse[]
   onLoadModels: () => void
+  onRefreshYoloPreflight: () => void
   onSelectDataset: (datasetId: string) => void
   onSelectModel: (modelId: string) => void
   onSetConfidenceThreshold: (value: number) => void
@@ -67,10 +72,14 @@ export function DetectionLab({
   detectionQaResult,
   detectionQaError,
   runningDetectionQa,
+  yoloPreflight,
+  loadingYoloPreflight,
+  yoloPreflightError,
   selectedProjectId,
   rasterDatasets,
   referenceDatasets,
   onLoadModels,
+  onRefreshYoloPreflight,
   onSelectDataset,
   onSelectModel,
   onSetConfidenceThreshold,
@@ -164,6 +173,76 @@ export function DetectionLab({
         </ul>
       </div>
 
+      <div className="ai-lab-model-surface" aria-label="YOLO runtime preflight">
+        <div className="ai-lab-section-header">
+          <div>
+            <h3>YOLO runtime preflight</h3>
+            <p>Read-only runtime status. This does not load a model, run inference or download weights.</p>
+          </div>
+          <button className="secondary-action" type="button" onClick={onRefreshYoloPreflight} disabled={loadingYoloPreflight}>
+            Refresh preflight
+          </button>
+        </div>
+        <div className="ai-lab-state-stack">
+          {loadingYoloPreflight ? (
+            <div className="result-state result-state-loading">
+              <strong>Loading YOLO preflight.</strong>
+              <p>Checking backend runtime configuration and optional dependency visibility.</p>
+            </div>
+          ) : null}
+          {yoloPreflightError ? (
+            <div className="result-state result-state-error">
+              <strong>YOLO preflight unavailable.</strong>
+              <p>{yoloPreflightError}</p>
+            </div>
+          ) : null}
+          {!yoloPreflight && !loadingYoloPreflight && !yoloPreflightError ? (
+            <div className="result-state result-state-empty">
+              <strong>No YOLO preflight loaded.</strong>
+              <p>Refresh preflight to inspect the live backend AI runtime before running configured YOLO.</p>
+            </div>
+          ) : null}
+        </div>
+        {yoloPreflight ? (
+          <div className={yoloPreflight.status === 'ready' ? 'lab-readiness-panel lab-readiness-panel-ready' : 'lab-readiness-panel'}>
+            <div className="ai-lab-section-header">
+              <div>
+                <h3>Status: {yoloPreflight.status}</h3>
+                <p>{yoloPreflight.message}</p>
+              </div>
+              <span className={yoloPreflight.status === 'ready' ? 'status-badge status-badge-ready' : 'status-badge'}>
+                {yoloPreflight.checks.dependencies_available ? 'dependencies visible' : 'not ready'}
+              </span>
+            </div>
+            <div className="lab-readiness-grid">
+              <div className={yoloPreflight.checks.enabled ? 'lab-readiness-item lab-readiness-item-ready' : 'lab-readiness-item'}>
+                <span>YOLO enabled</span>
+                <strong>{yoloPreflight.checks.enabled ? 'true' : 'false'}</strong>
+              </div>
+              <div className={yoloPreflight.checks.dependencies_available ? 'lab-readiness-item lab-readiness-item-ready' : 'lab-readiness-item'}>
+                <span>Dependencies</span>
+                <strong>{yoloPreflight.checks.dependencies_available === true ? 'available' : yoloPreflight.checks.dependencies_available === false ? 'unavailable' : 'not checked'}</strong>
+              </div>
+              <div className={yoloPreflight.checks.model_file_exists ? 'lab-readiness-item lab-readiness-item-ready' : 'lab-readiness-item'}>
+                <span>Local model file</span>
+                <strong>{yoloPreflight.checks.model_file_exists === true ? 'found' : yoloPreflight.checks.model_path_set ? 'missing' : 'not configured'}</strong>
+              </div>
+              <div className={yoloPreflight.runtime.cuda_available ? 'lab-readiness-item lab-readiness-item-ready' : 'lab-readiness-item'}>
+                <span>CUDA</span>
+                <strong>{yoloPreflight.runtime.cuda_available === true ? 'available' : yoloPreflight.runtime.cuda_available === false ? 'not available' : 'not checked'}</strong>
+              </div>
+            </div>
+            <div className="entity-meta">
+              <span>torch_version: {yoloPreflight.runtime.torch_version ?? 'n/a'}</span>
+              <span>ultralytics_version: {yoloPreflight.runtime.ultralytics_version ?? 'n/a'}</span>
+              <span>cuda_available: {String(yoloPreflight.runtime.cuda_available ?? 'unknown')}</span>
+              <span>YOLO_CONFIG_DIR: {yoloPreflight.runtime.yolo_config_dir ?? 'n/a'}</span>
+              <span>model directory: {yoloPreflight.runtime.model_directory ?? 'n/a'}</span>
+            </div>
+          </div>
+        ) : null}
+      </div>
+
       <div className="lab-block">
         <div className="ai-lab-run-surface" aria-label="Detection run controls">
           <h3>Run detection</h3>

frontend/src/hooks/useDetectionWorkflow.ts

@@ -8,6 +8,7 @@ import type {
   DetectionRunRead,
   DetectionRunResponse,
   QualityCheckRead,
+  YoloPreflightResponse,
 } from '../types'
 import { formatError } from '../lib/formatError'
 
@@ -47,6 +48,9 @@ export function useDetectionWorkflow({
   const [detectionQaResult, setDetectionQaResult] = useState<DetectionQaResult | null>(null)
   const [detectionQaError, setDetectionQaError] = useState<string | null>(null)
   const [runningDetectionQa, setRunningDetectionQa] = useState(false)
+  const [yoloPreflight, setYoloPreflight] = useState<YoloPreflightResponse | null>(null)
+  const [loadingYoloPreflight, setLoadingYoloPreflight] = useState(false)
+  const [yoloPreflightError, setYoloPreflightError] = useState<string | null>(null)
 
   const loadDetectionModels = async () => {
     setLoadingDetectionModels(true)
@@ -64,6 +68,21 @@ export function useDetectionWorkflow({
     }
   }
 
+  const loadYoloPreflight = async (tileManifestPath = detectionTileManifestPath) => {
+    setLoadingYoloPreflight(true)
+    setYoloPreflightError(null)
+    try {
+      const response = await detectionApi.getYoloPreflight({
+        tile_manifest_path: tileManifestPath.trim() || null,
+      })
+      setYoloPreflight(response)
+    } catch (error) {
+      setYoloPreflightError(formatError(error, 'Failed to load YOLO preflight status'))
+    } finally {
+      setLoadingYoloPreflight(false)
+    }
+  }
+
   const loadDetectionRuns = async (projectId = selectedProjectId) => {
     if (!projectId) {
       setDetectionRuns([])
@@ -199,7 +218,11 @@ export function useDetectionWorkflow({
     detectionQaResult,
     detectionQaError,
     runningDetectionQa,
+    yoloPreflight,
+    loadingYoloPreflight,
+    yoloPreflightError,
     loadDetectionModels,
+    loadYoloPreflight,
     loadDetectionRuns,
     loadDetectionResults,
     runDetection,

frontend/src/services/api/detection.ts

@@ -8,9 +8,10 @@ import type {
   DetectionRunRead,
   DetectionRunRequest,
   DetectionRunResponse,
+  YoloPreflightResponse,
 } from '../../types'
 
-function queryString(params: Record<string, string | number | null | undefined>): string {
+function queryString(params: Record<string, string | number | boolean | null | undefined>): string {
   const searchParams = new URLSearchParams()
   Object.entries(params).forEach(([key, value]) => {
     if (value !== null && value !== undefined && value !== '') {
@@ -23,6 +24,8 @@ function queryString(params: Record<string, string | number | null | undefined>)
 
 export const detectionApi = {
   listModels: (): Promise<DetectionModelsResponse> => apiGet<DetectionModelsResponse>('/api/v1/detection/models'),
+  getYoloPreflight: (params: { tile_manifest_path?: string | null; check_model_load?: boolean | null } = {}): Promise<YoloPreflightResponse> =>
+    apiGet<YoloPreflightResponse>(`/api/v1/detection/yolo/preflight${queryString(params)}`),
   run: (payload: DetectionRunRequest): Promise<DetectionRunResponse> =>
     apiPost<DetectionRunResponse>('/api/v1/detection/run', payload),
   listRuns: (params: { project_id?: string | null; dataset_id?: string | null } = {}): Promise<DetectionRunListResponse> =>

frontend/src/types.ts

@@ -404,6 +404,43 @@ export interface DetectionModelsResponse {
   models: DetectionModelCapability[]
 }
 
+export interface YoloPreflightChecks {
+  enabled: boolean
+  dependencies_available?: boolean | null
+  model_path_set?: boolean | null
+  model_file_exists?: boolean | null
+  model_load_requested: boolean
+  model_load_ok?: boolean | null
+  manifest_path_set?: boolean | null
+  manifest_valid?: boolean | null
+  tile_paths_exist?: boolean | null
+  tile_limit_ok?: boolean | null
+}
+
+export interface YoloPreflightRuntime {
+  dependencies_assumed: boolean
+  model_directory?: string | null
+  yolo_config_dir?: string | null
+  torch_version?: string | null
+  ultralytics_version?: string | null
+  cuda_available?: boolean | null
+}
+
+export interface YoloPreflightResponse {
+  model_id: string
+  model_path?: string | null
+  tile_manifest_path?: string | null
+  status: string
+  message: string
+  checks: YoloPreflightChecks
+  runtime: YoloPreflightRuntime
+  tile_count: number
+  max_tiles: number
+  will_download_models: boolean
+  will_run_inference: boolean
+  error_code?: string | null
+}
+
 export interface DetectionRunRequest {
   project_id: string
   dataset_id: string