fix(ai-fal): handle errors from fal result fetch on completed jobs

.changeset/fix-fal-failed-status.md

@@ -0,0 +1,7 @@
+---
+'@tanstack/ai-fal': patch
+---
+
+fix: handle FAILED queue status from fal.ai to prevent infinite polling
+
+Added `FAILED` to `FalQueueStatus` type and mapped it to `'failed'` status. Changed the default case in status mapping from `'processing'` to `'failed'` so unknown statuses don't cause infinite polling. Error details from the fal response are now surfaced in `VideoStatusResult.error`.

packages/typescript/ai-fal/package.json

@@ -41,7 +41,7 @@
     "video-generation"
   ],
   "dependencies": {
-    "@fal-ai/client": "^1.9.1"
+    "@fal-ai/client": "^1.9.4"
   },
   "devDependencies": {
     "@tanstack/ai": "workspace:*",

packages/typescript/ai-fal/src/adapters/video.ts

@@ -16,12 +16,13 @@ import type {
 } from '../model-meta'
 import type { FalClientConfig } from '../utils'
 
-type FalQueueStatus = 'IN_QUEUE' | 'IN_PROGRESS' | 'COMPLETED'
+type FalQueueStatus = 'IN_QUEUE' | 'IN_PROGRESS' | 'COMPLETED' | 'FAILED'
 
 interface FalStatusResponse {
   status: FalQueueStatus
   queue_position?: number
   logs?: Array<{ message: string }>
+  error?: string
 }
 
 interface FalVideoResultData {
@@ -42,8 +43,10 @@ function mapFalStatusToVideoStatus(
       return 'processing'
     case 'COMPLETED':
       return 'completed'
+    case 'FAILED':
+      return 'failed'
     default:
-      return 'processing'
+      return 'failed'
   }
 }
 
@@ -110,6 +113,7 @@ export class FalVideoAdapter<TModel extends FalModel> extends BaseVideoAdapter<
         statusResponse.queue_position != null
           ? Math.max(0, 100 - statusResponse.queue_position * 10)
           : undefined,
+      error: statusResponse.error,
     }
   }
 

packages/typescript/ai-fal/tests/video-adapter.test.ts

@@ -199,6 +199,32 @@ describe('Fal Video Adapter', () => {
 
       expect(result.status).toBe('completed')
     })
+
+    it('returns failed status with error for failed jobs', async () => {
+      mockQueueStatus.mockResolvedValueOnce({
+        status: 'FAILED',
+        error: 'Validation error: invalid input',
+      })
+
+      const adapter = createAdapter()
+
+      const result = await adapter.getVideoStatus('job-failed')
+
+      expect(result.status).toBe('failed')
+      expect(result.error).toBe('Validation error: invalid input')
+    })
+
+    it('returns failed status for unknown statuses', async () => {
+      mockQueueStatus.mockResolvedValueOnce({
+        status: 'UNKNOWN_STATUS',
+      })
+
+      const adapter = createAdapter()
+
+      const result = await adapter.getVideoStatus('job-unknown')
+
+      expect(result.status).toBe('failed')
+    })
   })
 
   describe('getVideoUrl', () => {