diff --git a/apps/sim/app/api/knowledge/[id]/documents/[documentId]/chunks/route.test.ts b/apps/sim/app/api/knowledge/[id]/documents/[documentId]/chunks/route.test.ts
new file mode 100644
index 00000000000..152186137e7
--- /dev/null
+++ b/apps/sim/app/api/knowledge/[id]/documents/[documentId]/chunks/route.test.ts
@@ -0,0 +1,63 @@
+/**
+ * @vitest-environment node
+ */
+
+import { authMockFns, createMockRequest } from '@sim/testing'
+import { beforeEach, describe, expect, it, vi } from 'vitest'
+
+const mocks = vi.hoisted(() => ({
+  list: vi.fn(),
+  create: vi.fn(),
+  bulk: vi.fn(),
+}))
+
+vi.mock('@/lib/knowledge/application/chunks', () => ({
+  listKnowledgeChunks: {
+    operation: { id: 'knowledge.chunks.list' },
+    execute: mocks.list,
+  },
+  createKnowledgeChunk: {
+    operation: { id: 'knowledge.chunks.create' },
+    execute: mocks.create,
+  },
+  bulkUpdateKnowledgeChunks: {
+    operation: { id: 'knowledge.chunks.bulk' },
+    execute: mocks.bulk,
+  },
+}))
+
+vi.mock('@/app/api/knowledge/secret-provenance', () => ({
+  finalizeKnowledgePersistedResponse: vi.fn(),
+  finalizeKnowledgeProvenanceResponse: vi.fn(),
+  resolveKnowledgeWriteSecretProvenance: vi.fn(),
+}))
+
+import { KnowledgeDocumentNotReadyError } from '@/lib/knowledge/application/chunk-errors'
+import { GET } from '@/app/api/knowledge/[id]/documents/[documentId]/chunks/route'
+
+const params = () => ({
+  params: Promise.resolve({ id: 'knowledge-1', documentId: 'document-1' }),
+})
+
+describe('/api/knowledge/[id]/documents/[documentId]/chunks internal route composition', () => {
+  beforeEach(() => {
+    vi.clearAllMocks()
+    authMockFns.mockGetSession.mockResolvedValue({
+      user: { id: 'user-1' },
+      session: { id: 'session-1' },
+    })
+  })
+
+  it('preserves retry metadata when a document is still processing', async () => {
+    mocks.list.mockRejectedValueOnce(new KnowledgeDocumentNotReadyError('processing'))
+
+    const response = await GET(createMockRequest('GET'), params())
+
+    expect(response.status).toBe(400)
+    await expect(response.json()).resolves.toEqual({
+      error: 'Document is not ready for access',
+      details: 'Document status: processing',
+      retryAfter: 5,
+    })
+  })
+})
diff --git a/apps/sim/app/api/knowledge/[id]/documents/[documentId]/chunks/route.ts b/apps/sim/app/api/knowledge/[id]/documents/[documentId]/chunks/route.ts
index c7461356308..d805898f287 100644
--- a/apps/sim/app/api/knowledge/[id]/documents/[documentId]/chunks/route.ts
+++ b/apps/sim/app/api/knowledge/[id]/documents/[documentId]/chunks/route.ts
@@ -54,7 +54,7 @@ export const GET = defineInternalJsonRoute({
   auth: internalKnowledgeSessionOrExecutorAuth,
   operation: knowledgeOperations.listChunks,
   rateLimit: internalRateLimits.none({ reason: 'Preserve existing internal chunk-list behavior' }),
-  errorPolicy: internalKnowledgeErrorPolicies.chunks,
+  errorPolicy: internalKnowledgeErrorPolicies.chunkList,
   mapInput: ({ params, query }) => ({
     knowledgeBaseId: params.id,
     documentId: params.documentId,
diff --git a/apps/sim/app/api/v2/files/[fileId]/route.test.ts b/apps/sim/app/api/v2/files/[fileId]/route.test.ts
index 770f1eafddd..a63dbb5c50a 100644
--- a/apps/sim/app/api/v2/files/[fileId]/route.test.ts
+++ b/apps/sim/app/api/v2/files/[fileId]/route.test.ts
@@ -141,6 +141,25 @@ describe('v2 single-file routes', () => {
     })
   })
 
+  it('encodes special characters in the extended download filename', async () => {
+    mocks.download.mockResolvedValueOnce({
+      file: fileRecord({ name: "it's (final)* café.pdf" }),
+      stream: new Blob(['pdf']).stream(),
+      contentType: 'application/pdf',
+      contentLength: 3,
+    })
+
+    const response = await GET(
+      new NextRequest(`http://localhost:3000/api/v2/files/${FILE_ID}?workspaceId=${WORKSPACE_ID}`),
+      context
+    )
+
+    expect(response.status).toBe(200)
+    expect(response.headers.get('Content-Disposition')).toBe(
+      `attachment; filename="it's (final)* caf_.pdf"; filename*=UTF-8''it%27s%20%28final%29%2A%20caf%C3%A9.pdf`
+    )
+  })
+
   it('conceals cross-workspace download authorization', async () => {
     mocks.download.mockRejectedValue(new NoWorkspaceAccessError())
 
diff --git a/apps/sim/app/api/v2/files/[fileId]/route.ts b/apps/sim/app/api/v2/files/[fileId]/route.ts
index 10b1ca6c94d..0a7bbc896bc 100644
--- a/apps/sim/app/api/v2/files/[fileId]/route.ts
+++ b/apps/sim/app/api/v2/files/[fileId]/route.ts
@@ -14,6 +14,7 @@ import { deleteWorkspaceFileOperation } from '@/lib/workspace-files/application/
 import { downloadWorkspaceFileStream } from '@/lib/workspace-files/application/download-workspace-file'
 import { fileOperations } from '@/lib/workspace-files/application/operations'
 import { renameWorkspaceFile } from '@/lib/workspace-files/application/rename-workspace-file'
+import { encodeFilenameForHeader } from '@/app/api/files/utils'
 import { toV2File } from '@/app/api/v2/files/utils'
 
 export const dynamic = 'force-dynamic'
@@ -42,7 +43,7 @@ export const GET = defineV2BinaryRoute({
   present: ({ file, stream, contentType, contentLength }) => ({
     body: stream,
     contentType,
-    contentDisposition: `attachment; filename="${file.name.replace(/[^\w.-]/g, '_')}"; filename*=UTF-8''${encodeURIComponent(file.name)}`,
+    contentDisposition: `attachment; ${encodeFilenameForHeader(file.name)}`,
     contentLength,
   }),
 })
diff --git a/apps/sim/app/api/v2/knowledge/[id]/documents/route.test.ts b/apps/sim/app/api/v2/knowledge/[id]/documents/route.test.ts
index 401d0f63f9b..1b03a060bbe 100644
--- a/apps/sim/app/api/v2/knowledge/[id]/documents/route.test.ts
+++ b/apps/sim/app/api/v2/knowledge/[id]/documents/route.test.ts
@@ -17,7 +17,6 @@ const {
   mockUploadDocument,
   mockReadFormData,
   mockReadFile,
-  mockUploadWorkspaceFile,
   mockPlatformUploaded,
   mockCapture,
   mockIsPayloadSizeLimitError,
@@ -26,7 +25,6 @@ const {
   mockUploadDocument: vi.fn(),
   mockReadFormData: vi.fn(),
   mockReadFile: vi.fn(),
-  mockUploadWorkspaceFile: vi.fn(),
   mockPlatformUploaded: vi.fn(),
   mockCapture: vi.fn(),
   mockIsPayloadSizeLimitError: vi.fn(),
@@ -58,10 +56,6 @@ vi.mock('@/lib/core/utils/stream-limits', () => ({
   readFileToBufferWithLimit: mockReadFile,
 }))
 
-vi.mock('@/lib/uploads/contexts/workspace', () => ({
-  uploadWorkspaceFile: mockUploadWorkspaceFile,
-}))
-
 vi.mock('@/lib/core/telemetry', () => ({
   PlatformEvents: { knowledgeBaseDocumentsUploaded: mockPlatformUploaded },
 }))
@@ -102,13 +96,11 @@ describe('POST /api/v2/knowledge/[id]/documents', () => {
       knowledgeBaseId: 'kb-1',
       knowledgeBaseName: 'Support docs',
       workspaceId: WORKSPACE_ID,
-      storageActorUserId: 'user-1',
     })
     const formData = new FormData()
     formData.set('file', new File(['hello'], 'support.txt', { type: 'text/plain' }))
     mockReadFormData.mockResolvedValue(formData)
     mockReadFile.mockResolvedValue(Buffer.from('hello'))
-    mockUploadWorkspaceFile.mockResolvedValue({ url: 's3://workspace/support.txt' })
     mockUploadDocument.mockResolvedValue({
       created: true,
       document: {
@@ -141,21 +133,14 @@ describe('POST /api/v2/knowledge/[id]/documents', () => {
       input: { knowledgeBaseId: 'kb-1', assertedWorkspaceId: WORKSPACE_ID },
       request,
     })
-    expect(mockUploadWorkspaceFile).toHaveBeenCalledWith(
-      WORKSPACE_ID,
-      'user-1',
-      Buffer.from('hello'),
-      'support.txt',
-      'text/plain'
-    )
     expect(mockUploadDocument).toHaveBeenCalledWith({
       principal: PRINCIPAL,
       input: {
         knowledgeBaseId: 'kb-1',
         assertedWorkspaceId: WORKSPACE_ID,
-        document: {
+        file: {
+          buffer: Buffer.from('hello'),
           filename: 'support.txt',
-          fileUrl: 's3://workspace/support.txt',
           fileSize: 5,
           mimeType: 'text/plain',
         },
@@ -194,7 +179,6 @@ describe('POST /api/v2/knowledge/[id]/documents', () => {
       error: { code: 'USAGE_LIMIT_EXCEEDED', message: 'Upgrade required' },
     })
     expect(mockReadFormData).not.toHaveBeenCalled()
-    expect(mockUploadWorkspaceFile).not.toHaveBeenCalled()
     expect(mockUploadDocument).not.toHaveBeenCalled()
   })
 
@@ -214,7 +198,7 @@ describe('POST /api/v2/knowledge/[id]/documents', () => {
     expect(mockCapture).not.toHaveBeenCalled()
   })
 
-  it('preserves the malformed multipart envelope without transferring storage', async () => {
+  it('preserves the malformed multipart envelope without entering the upload operation', async () => {
     mockReadFormData.mockRejectedValueOnce(new Error('multipart boundary missing'))
 
     const response = await POST(buildRequest(), { params: Promise.resolve({ id: 'kb-1' }) })
@@ -223,12 +207,11 @@ describe('POST /api/v2/knowledge/[id]/documents', () => {
     expect(await response.json()).toEqual({
       error: { code: 'BAD_REQUEST', message: 'Request body must be valid multipart form data' },
     })
-    expect(mockUploadWorkspaceFile).not.toHaveBeenCalled()
     expect(mockUploadDocument).not.toHaveBeenCalled()
     expect(mockPlatformUploaded).not.toHaveBeenCalled()
   })
 
-  it('preserves bounded multipart rejection and stops before storage transfer', async () => {
+  it('preserves bounded multipart rejection and stops before the upload operation', async () => {
     const error = new Error('knowledge document upload body exceeds maximum size')
     mockReadFormData.mockRejectedValueOnce(error)
     mockIsPayloadSizeLimitError.mockImplementation((candidate: unknown) => candidate === error)
@@ -239,11 +222,10 @@ describe('POST /api/v2/knowledge/[id]/documents', () => {
     expect(await response.json()).toEqual({
       error: { code: 'PAYLOAD_TOO_LARGE', message: error.message },
     })
-    expect(mockUploadWorkspaceFile).not.toHaveBeenCalled()
     expect(mockUploadDocument).not.toHaveBeenCalled()
   })
 
-  it('requires a file form field before storage transfer', async () => {
+  it('requires a file form field before the upload operation', async () => {
     mockReadFormData.mockResolvedValueOnce(new FormData())
 
     const response = await POST(buildRequest(), { params: Promise.resolve({ id: 'kb-1' }) })
@@ -252,7 +234,7 @@ describe('POST /api/v2/knowledge/[id]/documents', () => {
     expect(await response.json()).toEqual({
       error: { code: 'BAD_REQUEST', message: 'file form field is required' },
     })
-    expect(mockUploadWorkspaceFile).not.toHaveBeenCalled()
+    expect(mockUploadDocument).not.toHaveBeenCalled()
   })
 
   it('preserves the exact file-size rejection before reading file bytes', async () => {
@@ -269,7 +251,7 @@ describe('POST /api/v2/knowledge/[id]/documents', () => {
       error: { code: 'PAYLOAD_TOO_LARGE', message: 'File size exceeds 100MB limit (100.00MB)' },
     })
     expect(mockReadFile).not.toHaveBeenCalled()
-    expect(mockUploadWorkspaceFile).not.toHaveBeenCalled()
+    expect(mockUploadDocument).not.toHaveBeenCalled()
   })
 
   it('preserves unsupported file-type validation before reading file bytes', async () => {
@@ -286,11 +268,11 @@ describe('POST /api/v2/knowledge/[id]/documents', () => {
       error: { code: 'UNSUPPORTED_MEDIA_TYPE', message: expectedMessage },
     })
     expect(mockReadFile).not.toHaveBeenCalled()
-    expect(mockUploadWorkspaceFile).not.toHaveBeenCalled()
+    expect(mockUploadDocument).not.toHaveBeenCalled()
   })
 
-  it('does not register or emit effects when storage transfer fails', async () => {
-    mockUploadWorkspaceFile.mockRejectedValueOnce(new Error('storage unavailable'))
+  it('does not emit effects when the upload operation fails', async () => {
+    mockUploadDocument.mockRejectedValueOnce(new Error('storage unavailable'))
 
     const response = await POST(buildRequest(), { params: Promise.resolve({ id: 'kb-1' }) })
 
@@ -298,12 +280,12 @@ describe('POST /api/v2/knowledge/[id]/documents', () => {
     expect(await response.json()).toEqual({
       error: { code: 'INTERNAL_ERROR', message: 'Internal server error' },
     })
-    expect(mockUploadDocument).not.toHaveBeenCalled()
+    expect(mockUploadDocument).toHaveBeenCalledOnce()
     expect(mockPlatformUploaded).not.toHaveBeenCalled()
     expect(mockCapture).not.toHaveBeenCalled()
   })
 
-  it('preserves application authorization errors after storage transfer', async () => {
+  it('preserves final application authorization errors', async () => {
     mockUploadDocument.mockRejectedValueOnce(
       new OrchestrationError('forbidden', 'Insufficient workspace permissions')
     )
@@ -314,7 +296,7 @@ describe('POST /api/v2/knowledge/[id]/documents', () => {
     expect(await response.json()).toEqual({
       error: { code: 'FORBIDDEN', message: 'Insufficient workspace permissions' },
     })
-    expect(mockUploadWorkspaceFile).toHaveBeenCalledOnce()
+    expect(mockUploadDocument).toHaveBeenCalledOnce()
     expect(mockPlatformUploaded).not.toHaveBeenCalled()
     expect(mockCapture).not.toHaveBeenCalled()
   })
diff --git a/apps/sim/app/api/v2/knowledge/[id]/documents/route.ts b/apps/sim/app/api/v2/knowledge/[id]/documents/route.ts
index 62871ad988f..6ba62a1a941 100644
--- a/apps/sim/app/api/v2/knowledge/[id]/documents/route.ts
+++ b/apps/sim/app/api/v2/knowledge/[id]/documents/route.ts
@@ -26,7 +26,6 @@ import {
 import { knowledgeOperations } from '@/lib/knowledge/application/operations'
 import { KnowledgeDocumentUnsupportedMediaTypeError } from '@/lib/knowledge/application/upload-sessions'
 import { captureServerEvent } from '@/lib/posthog/server'
-import { uploadWorkspaceFile } from '@/lib/uploads/contexts/workspace'
 import { MAX_KNOWLEDGE_DOCUMENT_FILE_SIZE } from '@/lib/uploads/shared/types'
 import { validateFileType } from '@/lib/uploads/utils/validation'
 import { serializeDate } from '@/app/api/v1/knowledge/utils'
@@ -138,20 +137,12 @@ export const POST = defineV2BodyLifecycleRoute({
     })
     return { file: rawFile, buffer, contentType }
   },
-  transfer: ({ admission, body }) =>
-    uploadWorkspaceFile(
-      admission.workspaceId,
-      admission.storageActorUserId,
-      body.buffer,
-      body.file.name,
-      body.contentType
-    ),
-  mapInput: ({ parsed, body, transfer }) => ({
+  mapInput: ({ parsed, body }) => ({
     knowledgeBaseId: parsed.params.id,
     assertedWorkspaceId: parsed.query.workspaceId,
-    document: {
+    file: {
+      buffer: body.buffer,
       filename: body.file.name,
-      fileUrl: transfer.url,
       fileSize: body.file.size,
       mimeType: body.contentType,
     },
diff --git a/apps/sim/app/api/webhooks/outbox/process/route.ts b/apps/sim/app/api/webhooks/outbox/process/route.ts
index 5a150e66ac7..a9edf8bc231 100644
--- a/apps/sim/app/api/webhooks/outbox/process/route.ts
+++ b/apps/sim/app/api/webhooks/outbox/process/route.ts
@@ -9,6 +9,7 @@ import { billingOutboxHandlers } from '@/lib/billing/webhooks/outbox-handlers'
 import { processOutboxEvents } from '@/lib/core/outbox/service'
 import { generateRequestId } from '@/lib/core/utils/request'
 import { withRouteHandler } from '@/lib/core/utils/with-route-handler'
+import { knowledgeDocumentProcessingOutboxHandlers } from '@/lib/knowledge/documents/processing-outbox-handler'
 import { workflowDeploymentOutboxHandlers } from '@/lib/workflows/deployment-outbox'
 import { invitationMigrationOutboxHandlers } from '@/lib/workspaces/admin-move'
 import { reapStaleBackgroundWork } from '@/ee/workspace-forking/lib/background-work/store'
@@ -23,6 +24,7 @@ const handlers = {
   ...membershipBillingOutboxHandlers,
   ...enterpriseIssuanceOutboxHandlers,
   ...invitationMigrationOutboxHandlers,
+  ...knowledgeDocumentProcessingOutboxHandlers,
   ...workflowDeploymentOutboxHandlers,
 } as const
 
diff --git a/apps/sim/lib/api/server/routes/v2-body-lifecycle-route.test.ts b/apps/sim/lib/api/server/routes/v2-body-lifecycle-route.test.ts
index f0d940e8abb..6885f3d1a4d 100644
--- a/apps/sim/lib/api/server/routes/v2-body-lifecycle-route.test.ts
+++ b/apps/sim/lib/api/server/routes/v2-body-lifecycle-route.test.ts
@@ -43,7 +43,7 @@ const contract = defineRouteContract({
 
 class StageRejection extends Error {}
 
-type RejectableStage = 'admission' | 'body' | 'transfer' | 'application' | 'presenter' | 'effects'
+type RejectableStage = 'admission' | 'body' | 'application' | 'presenter' | 'effects'
 
 let rejectedStage: RejectableStage | null = null
 
@@ -80,11 +80,10 @@ function buildHandler() {
       rejectAt('body')
       return { bytes: Buffer.from('body') }
     },
-    async transfer({ admission }) {
-      rejectAt('transfer')
-      return { url: `stored://${admission.canonicalWorkspaceId}` }
-    },
-    mapInput: ({ parsed, transfer }) => ({ id: parsed.params.id, url: transfer.url }),
+    mapInput: ({ parsed, admission }) => ({
+      id: parsed.params.id,
+      url: `stored://${admission.canonicalWorkspaceId}`,
+    }),
     useCase: {
       operation,
       async execute({ input }) {
@@ -161,7 +160,6 @@ describe('defineV2BodyLifecycleRoute', () => {
         errorPolicy: { render: () => null },
         admission: { mapInput: () => ({}), useCase },
         readBody: async () => Buffer.alloc(0),
-        transfer: async () => ({ url: 'stored://item-1' }),
         mapInput: () => ({}),
         useCase,
         present: () => ({ data: { id: 'item-1' } }),
@@ -183,7 +181,6 @@ describe('defineV2BodyLifecycleRoute', () => {
       'contract',
       'admission',
       'body',
-      'transfer',
       'application',
       'presenter',
       'effects',
@@ -260,24 +257,20 @@ describe('defineV2BodyLifecycleRoute', () => {
     ])
   })
 
-  it.each<RejectableStage>([
-    'admission',
-    'body',
-    'transfer',
-    'application',
-    'presenter',
-    'effects',
-  ])('renders typed %s rejection without entering later phases', async (stage) => {
-    rejectedStage = stage
+  it.each<RejectableStage>(['admission', 'body', 'application', 'presenter', 'effects'])(
+    'renders typed %s rejection without entering later phases',
+    async (stage) => {
+      rejectedStage = stage
 
-    const response = await buildHandler()(buildRequest(), context())
+      const response = await buildHandler()(buildRequest(), context())
 
-    expect(response.status).toBe(409)
-    expect(await response.json()).toEqual({
-      error: { code: 'CONFLICT', message: `${stage} rejected` },
-    })
-    expect(mocks.order.at(-1)).toBe(stage)
-  })
+      expect(response.status).toBe(409)
+      expect(await response.json()).toEqual({
+        error: { code: 'CONFLICT', message: `${stage} rejected` },
+      })
+      expect(mocks.order.at(-1)).toBe(stage)
+    }
+  )
 
   it.each(['authentication', 'rollout', 'rate_limit'] as const)(
     'maps %s infrastructure failures to service unavailable',
diff --git a/apps/sim/lib/api/server/routes/v2-body-lifecycle-route.ts b/apps/sim/lib/api/server/routes/v2-body-lifecycle-route.ts
index f5e04983e58..a6c415ec493 100644
--- a/apps/sim/lib/api/server/routes/v2-body-lifecycle-route.ts
+++ b/apps/sim/lib/api/server/routes/v2-body-lifecycle-route.ts
@@ -41,18 +41,13 @@ interface V2BodyLifecycleContext<C extends JsonApiRouteContract, A> {
   admission: A
 }
 
-interface V2BodyLifecycleTransferContext<C extends JsonApiRouteContract, A, B>
+interface V2BodyLifecycleInputContext<C extends JsonApiRouteContract, A, B>
   extends V2BodyLifecycleContext<C, A> {
   body: B
 }
 
-interface V2BodyLifecycleInputContext<C extends JsonApiRouteContract, A, B, T>
-  extends V2BodyLifecycleTransferContext<C, A, B> {
-  transfer: T
-}
-
-interface V2BodyLifecycleSuccessContext<C extends JsonApiRouteContract, A, B, T, I, R>
-  extends V2BodyLifecycleInputContext<C, A, B, T> {
+interface V2BodyLifecycleSuccessContext<C extends JsonApiRouteContract, A, B, I, R>
+  extends V2BodyLifecycleInputContext<C, A, B> {
   input: I
   result: R
 }
@@ -63,7 +58,6 @@ interface V2BodyLifecycleRouteOptions<
   AI,
   A,
   B,
-  T,
   I,
   R,
 > {
@@ -75,12 +69,11 @@ interface V2BodyLifecycleRouteOptions<
   parseOptions?: Omit<ParseRequestOptions, 'validationErrorResponse'>
   admission: V2BodyLifecycleAdmission<O, C, AI, A>
   readBody(context: V2BodyLifecycleContext<C, A>): Promise<B>
-  transfer(context: V2BodyLifecycleTransferContext<C, A, B>): Promise<T>
-  mapInput(context: V2BodyLifecycleInputContext<C, A, B, T>): I
+  mapInput(context: V2BodyLifecycleInputContext<C, A, B>): I
   useCase: OperationUseCase<NoInfer<O>, I, R>
   present(result: R): ContractJsonResponse<C> | Promise<ContractJsonResponse<C>>
   onSuccess?(
-    context: V2BodyLifecycleSuccessContext<C, A, B, T, NoInfer<I>, NoInfer<R>>
+    context: V2BodyLifecycleSuccessContext<C, A, B, NoInfer<I>, NoInfer<R>>
   ): void | Promise<void>
 }
 
@@ -95,10 +88,9 @@ export function defineV2BodyLifecycleRoute<
   AI,
   A,
   B,
-  T,
   I,
   R,
->(options: V2BodyLifecycleRouteOptions<C, O, AI, A, B, T, I, R>): JsonNextRouteHandler {
+>(options: V2BodyLifecycleRouteOptions<C, O, AI, A, B, I, R>): JsonNextRouteHandler {
   if (options.contract.body) {
     throw new Error(
       `${options.contract.method} ${options.contract.path} must omit its body schema so admission precedes body reads`
@@ -153,8 +145,7 @@ export function defineV2BodyLifecycleRoute<
         })
         const lifecycleContext = { request, principal, parsed: parsed.data, admission }
         const body = await options.readBody(lifecycleContext)
-        const transfer = await options.transfer({ ...lifecycleContext, body })
-        const inputContext = { ...lifecycleContext, body, transfer }
+        const inputContext = { ...lifecycleContext, body }
         const input = options.mapInput(inputContext)
         const result = await options.useCase.execute({ principal, input, request })
         const responseBody = options.contract.response.schema.parse(await options.present(result))
diff --git a/apps/sim/lib/knowledge/api/route-policies.ts b/apps/sim/lib/knowledge/api/route-policies.ts
index 22628d413fe..b9ae9031575 100644
--- a/apps/sim/lib/knowledge/api/route-policies.ts
+++ b/apps/sim/lib/knowledge/api/route-policies.ts
@@ -2,6 +2,7 @@ import {
   createInternalResourceConcealmentPolicy,
   createInternalSessionOrExecutorAuth,
   createV2ResourceConcealmentPolicy,
+  extendInternalErrorPolicy,
   type InternalErrorPolicy,
   internalErrorResponse,
   internalOrchestrationErrorPolicy,
@@ -11,6 +12,7 @@ import {
 import { isPayloadSizeLimitError } from '@/lib/core/utils/stream-limits'
 import { KNOWLEDGE_DELEGATION_AUDIENCE } from '@/lib/knowledge/application/authorization'
 import { KnowledgeUsageLimitExceededError } from '@/lib/knowledge/application/billing'
+import { KnowledgeDocumentNotReadyError } from '@/lib/knowledge/application/chunk-errors'
 import { KnowledgeSearchProvenanceUnavailableError } from '@/lib/knowledge/application/search'
 import { KnowledgeDocumentUnsupportedMediaTypeError } from '@/lib/knowledge/application/upload-sessions'
 import { v2Error } from '@/app/api/v2/lib/response'
@@ -82,6 +84,19 @@ export const internalKnowledgeErrorPolicies = {
   chunks: concealKnowledgeBase(
     internalKnowledgeErrorPolicy('Failed to process knowledge chunk request')
   ),
+  chunkList: concealKnowledgeBase(
+    extendInternalErrorPolicy(
+      internalKnowledgeErrorPolicy('Failed to process knowledge chunk request'),
+      (error) =>
+        error instanceof KnowledgeDocumentNotReadyError
+          ? internalErrorResponse(400, {
+              error: 'Document is not ready for access',
+              details: `Document status: ${error.processingStatus}`,
+              retryAfter: error.processingStatus === 'processing' ? 5 : null,
+            })
+          : null
+    )
+  ),
   upsert: concealKnowledgeBase(internalKnowledgeUploadErrorPolicy),
   search: concealKnowledgeBase(internalKnowledgeSearchErrorPolicy),
   tags: concealKnowledgeBase(
diff --git a/apps/sim/lib/knowledge/application/chunk-errors.ts b/apps/sim/lib/knowledge/application/chunk-errors.ts
new file mode 100644
index 00000000000..a56c22bb485
--- /dev/null
+++ b/apps/sim/lib/knowledge/application/chunk-errors.ts
@@ -0,0 +1,8 @@
+import { OrchestrationError } from '@/lib/core/orchestration/types'
+
+export class KnowledgeDocumentNotReadyError extends OrchestrationError {
+  constructor(readonly processingStatus: string) {
+    super('validation', `Document is not ready for access (status: ${processingStatus})`)
+    this.name = 'KnowledgeDocumentNotReadyError'
+  }
+}
diff --git a/apps/sim/lib/knowledge/application/chunks.test.ts b/apps/sim/lib/knowledge/application/chunks.test.ts
new file mode 100644
index 00000000000..74b93781ad3
--- /dev/null
+++ b/apps/sim/lib/knowledge/application/chunks.test.ts
@@ -0,0 +1,79 @@
+/**
+ * @vitest-environment node
+ */
+
+import { beforeEach, describe, expect, it, vi } from 'vitest'
+
+const mocks = vi.hoisted(() => ({
+  resolveDocument: vi.fn(),
+  resolvePermission: vi.fn(),
+  queryChunks: vi.fn(),
+}))
+
+vi.mock('@sim/platform-authz/workspace', () => ({
+  permissionSatisfies: (actual: string | null, required: string) => {
+    const rank = { read: 1, write: 2, admin: 3 } as const
+    return (
+      actual !== null && rank[actual as keyof typeof rank] >= rank[required as keyof typeof rank]
+    )
+  },
+  resolveEffectiveWorkspacePermission: mocks.resolvePermission,
+}))
+
+vi.mock('@/lib/knowledge/application/contexts', () => ({
+  resolveCanonicalActiveKnowledgeDocumentContext: mocks.resolveDocument,
+  resolveActiveKnowledgeChunkContext: vi.fn(),
+}))
+
+vi.mock('@/lib/knowledge/chunks/service', () => ({
+  batchChunkOperation: vi.fn(),
+  createChunk: vi.fn(),
+  deleteChunk: vi.fn(),
+  queryChunks: mocks.queryChunks,
+  updateChunk: vi.fn(),
+}))
+
+vi.mock('@/lib/execution/durable-secret-provenance', () => ({
+  createDurableSecretProvenanceRegistry: vi.fn(),
+}))
+
+vi.mock('@/lib/knowledge/model-input-provenance', () => ({
+  runWithKnowledgeModelInputProvenance: vi.fn(),
+}))
+
+vi.mock('@/providers/utils', () => ({ calculateCost: vi.fn() }))
+
+import { KnowledgeDocumentNotReadyError } from '@/lib/knowledge/application/chunk-errors'
+import { listKnowledgeChunks } from '@/lib/knowledge/application/chunks'
+
+describe('knowledge chunk application use cases', () => {
+  beforeEach(() => {
+    vi.clearAllMocks()
+    mocks.resolvePermission.mockResolvedValue('read')
+    mocks.resolveDocument.mockResolvedValue({
+      workspaceId: 'workspace-1',
+      workspaceOrganizationId: null,
+      allowPersonalApiKeys: true,
+      billedAccountUserId: 'billing-owner-1',
+      knowledgeBaseId: 'knowledge-1',
+      knowledgeBase: { id: 'knowledge-1' },
+      documentId: 'document-1',
+      document: { id: 'document-1', processingStatus: 'processing' },
+    })
+  })
+
+  it('returns a typed transient failure before querying chunks for a processing document', async () => {
+    const promise = listKnowledgeChunks.execute({
+      principal: { kind: 'session', userId: 'user-1', sessionId: 'session-1' },
+      input: { knowledgeBaseId: 'knowledge-1', documentId: 'document-1' },
+    })
+
+    await expect(promise).rejects.toBeInstanceOf(KnowledgeDocumentNotReadyError)
+    await expect(promise).rejects.toMatchObject({
+      code: 'validation',
+      processingStatus: 'processing',
+      message: 'Document is not ready for access (status: processing)',
+    })
+    expect(mocks.queryChunks).not.toHaveBeenCalled()
+  })
+})
diff --git a/apps/sim/lib/knowledge/application/chunks.ts b/apps/sim/lib/knowledge/application/chunks.ts
index 519ac5b1198..3f81a5d5683 100644
--- a/apps/sim/lib/knowledge/application/chunks.ts
+++ b/apps/sim/lib/knowledge/application/chunks.ts
@@ -7,6 +7,7 @@ import {
 } from '@/lib/execution/durable-secret-provenance'
 import { defineAuthorizedKnowledgeUseCase } from '@/lib/knowledge/application/authorized-knowledge-use-case'
 import { resolveKnowledgeAttributedUserId } from '@/lib/knowledge/application/billing'
+import { KnowledgeDocumentNotReadyError } from '@/lib/knowledge/application/chunk-errors'
 import {
   type ActiveKnowledgeDocumentContext,
   resolveActiveKnowledgeChunkContext,
@@ -62,10 +63,7 @@ export interface BulkKnowledgeChunksInput extends KnowledgeDocumentChunkInput {
 
 function requireChunkReadable(context: ActiveKnowledgeDocumentContext): void {
   if (context.document.processingStatus !== 'completed') {
-    throw new OrchestrationError(
-      'validation',
-      `Document is not ready for access (status: ${context.document.processingStatus})`
-    )
+    throw new KnowledgeDocumentNotReadyError(context.document.processingStatus)
   }
 }
 
diff --git a/apps/sim/lib/knowledge/application/documents.test.ts b/apps/sim/lib/knowledge/application/documents.test.ts
index 21fd1734e69..8df17daf2ee 100644
--- a/apps/sim/lib/knowledge/application/documents.test.ts
+++ b/apps/sim/lib/knowledge/application/documents.test.ts
@@ -22,6 +22,9 @@ const mocks = vi.hoisted(() => ({
   performBulkUpload: vi.fn(),
   markTimedOut: vi.fn(),
   retryProcessing: vi.fn(),
+  uploadStoredFile: vi.fn(),
+  generateKnowledgeBaseFileKey: vi.fn(),
+  recordKnowledgeBaseFileOwnership: vi.fn(),
   recordAudit: vi.fn(),
   captureServerEvent: vi.fn(),
 }))
@@ -75,6 +78,18 @@ vi.mock('@/lib/knowledge/orchestration/documents', () => ({
   performRetryKnowledgeDocumentProcessing: mocks.retryProcessing,
 }))
 
+vi.mock('@/lib/uploads', () => ({
+  StorageService: { uploadFile: mocks.uploadStoredFile },
+}))
+
+vi.mock('@/lib/uploads/contexts/knowledge-base/knowledge-base-file-manager', () => ({
+  generateKnowledgeBaseFileKey: mocks.generateKnowledgeBaseFileKey,
+}))
+
+vi.mock('@/lib/uploads/server/metadata', () => ({
+  recordKnowledgeBaseFileOwnership: mocks.recordKnowledgeBaseFileOwnership,
+}))
+
 vi.mock('@/lib/posthog/server', () => ({ captureServerEvent: mocks.captureServerEvent }))
 
 import { OrchestrationError } from '@/lib/core/orchestration/types'
@@ -107,6 +122,20 @@ const document = {
   uploadedAt: new Date('2026-01-01T00:00:00Z'),
 }
 
+const uploadFile = {
+  buffer: Buffer.alloc(42, 'a'),
+  filename: 'guide.pdf',
+  fileSize: 42,
+  mimeType: 'application/pdf',
+}
+
+const storedDocumentInput = {
+  filename: uploadFile.filename,
+  fileUrl: '/api/files/serve/kb%2Fupload-1?context=knowledge-base',
+  fileSize: uploadFile.fileSize,
+  mimeType: uploadFile.mimeType,
+}
+
 describe('knowledge document application use cases', () => {
   beforeEach(() => {
     vi.clearAllMocks()
@@ -131,6 +160,15 @@ describe('knowledge document application use cases', () => {
       workspaceId: 'workspace-1',
     })
     mocks.checkUsage.mockResolvedValue({ isExceeded: false })
+    mocks.generateKnowledgeBaseFileKey.mockReturnValue('kb/upload-1')
+    mocks.uploadStoredFile.mockResolvedValue({
+      path: '/api/files/serve/kb%2Fupload-1',
+      key: 'kb/upload-1',
+      name: uploadFile.filename,
+      size: uploadFile.fileSize,
+      type: uploadFile.mimeType,
+    })
+    mocks.recordKnowledgeBaseFileOwnership.mockResolvedValue(undefined)
     mocks.createDocument.mockResolvedValue(document)
     mocks.updateDocument.mockResolvedValue(document)
     mocks.processQueue.mockResolvedValue(undefined)
@@ -254,20 +292,52 @@ describe('knowledge document application use cases', () => {
       input: {
         knowledgeBaseId: 'knowledge-1',
         assertedWorkspaceId: 'workspace-1',
-        document,
+        file: uploadFile,
         source: 'v2',
       },
     })
 
     expect(mocks.resolveSystemBilling).toHaveBeenCalledWith('workspace-1')
+    expect(mocks.recordKnowledgeBaseFileOwnership).toHaveBeenCalledWith({
+      key: 'kb/upload-1',
+      userId: 'billing-owner-1',
+      workspaceId: 'workspace-1',
+      originalName: 'guide.pdf',
+      contentType: 'application/pdf',
+      size: 42,
+    })
+    expect(mocks.uploadStoredFile).toHaveBeenCalledWith({
+      file: uploadFile.buffer,
+      fileName: uploadFile.filename,
+      contentType: uploadFile.mimeType,
+      context: 'knowledge-base',
+      customKey: 'kb/upload-1',
+      preserveKey: true,
+      persistMetadata: false,
+    })
+    expect(mocks.recordKnowledgeBaseFileOwnership.mock.invocationCallOrder[0]).toBeLessThan(
+      mocks.uploadStoredFile.mock.invocationCallOrder[0]
+    )
+    expect(mocks.uploadStoredFile.mock.invocationCallOrder[0]).toBeLessThan(
+      mocks.createDocument.mock.invocationCallOrder[0]
+    )
     expect(mocks.createDocument).toHaveBeenCalledWith(
-      document,
+      storedDocumentInput,
       'knowledge-1',
       expect.any(String),
       'billing-owner-1',
       undefined,
       undefined,
-      { expectedWorkspaceId: 'workspace-1' }
+      {
+        expectedWorkspaceId: 'workspace-1',
+        processing: {
+          processingOptions: {},
+          billingAttribution: {
+            actorUserId: 'billing-owner-1',
+            workspaceId: 'workspace-1',
+          },
+        },
+      }
     )
     expect(mocks.recordAudit).toHaveBeenCalledWith(
       expect.objectContaining({
@@ -291,7 +361,7 @@ describe('knowledge document application use cases', () => {
       input: {
         knowledgeBaseId: 'knowledge-1',
         assertedWorkspaceId: 'workspace-1',
-        document,
+        file: uploadFile,
         usageAdmission: 'pre_admitted',
       },
     })
@@ -300,6 +370,29 @@ describe('knowledge document application use cases', () => {
     expect(mocks.createDocument).toHaveBeenCalledOnce()
   })
 
+  it('leaves only a sweepable knowledge-base binding when final authorization fails', async () => {
+    mocks.resolvePermission.mockResolvedValueOnce('write').mockResolvedValueOnce(null)
+
+    await expect(
+      uploadKnowledgeDocument.execute({
+        principal: { kind: 'session', userId: 'user-1', sessionId: 'session-1' },
+        input: {
+          knowledgeBaseId: 'knowledge-1',
+          assertedWorkspaceId: 'workspace-1',
+          file: uploadFile,
+          usageAdmission: 'pre_admitted',
+        },
+      })
+    ).rejects.toMatchObject({ code: 'forbidden' })
+
+    expect(mocks.recordKnowledgeBaseFileOwnership).toHaveBeenCalledOnce()
+    expect(mocks.uploadStoredFile).toHaveBeenCalledWith(
+      expect.objectContaining({ context: 'knowledge-base', persistMetadata: false })
+    )
+    expect(mocks.createDocument).not.toHaveBeenCalled()
+    expect(mocks.recordAudit).not.toHaveBeenCalled()
+  })
+
   it('conceals a cross-knowledge-base document before deletion and audit', async () => {
     mocks.resolveDocument.mockRejectedValueOnce(
       new OrchestrationError('not_found', 'Document not found')
@@ -441,7 +534,7 @@ describe('knowledge document application use cases', () => {
         input: {
           knowledgeBaseId: 'knowledge-1',
           assertedWorkspaceId: 'workspace-1',
-          document,
+          file: uploadFile,
         },
       })
     ).rejects.toBe(failure)
@@ -449,6 +542,34 @@ describe('knowledge document application use cases', () => {
     expect(mocks.recordAudit).not.toHaveBeenCalled()
   })
 
+  it('commits a durable processing intent instead of dispatching from the request', async () => {
+    await uploadKnowledgeDocument.execute({
+      principal: { kind: 'session', userId: 'user-1', sessionId: 'session-1' },
+      input: {
+        knowledgeBaseId: 'knowledge-1',
+        assertedWorkspaceId: 'workspace-1',
+        file: uploadFile,
+        processingOptions: { recipe: 'default', lang: 'en' },
+      },
+    })
+
+    expect(mocks.createDocument).toHaveBeenCalledWith(
+      storedDocumentInput,
+      'knowledge-1',
+      expect.any(String),
+      'user-1',
+      undefined,
+      undefined,
+      expect.objectContaining({
+        processing: {
+          processingOptions: { recipe: 'default', lang: 'en' },
+          billingAttribution: { actorUserId: 'user-1', workspaceId: 'workspace-1' },
+        },
+      })
+    )
+    expect(mocks.processQueue).not.toHaveBeenCalled()
+  })
+
   it('bounds bulk document creation before billing or orchestration', async () => {
     await expect(
       createKnowledgeDocuments.execute({
diff --git a/apps/sim/lib/knowledge/application/documents.ts b/apps/sim/lib/knowledge/application/documents.ts
index 9be50d5c4d6..30b9445fbd3 100644
--- a/apps/sim/lib/knowledge/application/documents.ts
+++ b/apps/sim/lib/knowledge/application/documents.ts
@@ -39,7 +39,6 @@ import {
   bulkDocumentOperationByFilter,
   createDocumentRecords,
   createSingleDocument,
-  type DocumentData,
   deleteDocument,
   deleteKnowledgeDocumentInKnowledgeBase,
   getDocuments,
@@ -57,6 +56,9 @@ import {
   performUploadKnowledgeDocuments,
 } from '@/lib/knowledge/orchestration/documents'
 import type { KnowledgeDocumentWriteSecretProvenance } from '@/lib/knowledge/secret-provenance'
+import { StorageService } from '@/lib/uploads'
+import { generateKnowledgeBaseFileKey } from '@/lib/uploads/contexts/knowledge-base/knowledge-base-file-manager'
+import { recordKnowledgeBaseFileOwnership } from '@/lib/uploads/server/metadata'
 import { MAX_KNOWLEDGE_DOCUMENT_FILE_SIZE } from '@/lib/uploads/shared/types'
 import { validateFileType } from '@/lib/uploads/utils/validation'
 
@@ -101,7 +103,12 @@ export interface KnowledgeDocumentInput {
 }
 
 export interface UploadKnowledgeDocumentInput extends UploadKnowledgeDocumentAdmissionInput {
-  document: KnowledgeDocumentInput
+  file: {
+    buffer: Buffer
+    filename: string
+    fileSize: number
+    mimeType: string
+  }
   processingOptions?: ProcessingOptions
   startProcessing?: boolean
   /** Code-defined admission state; HTTP/model payloads must never populate it. */
@@ -241,7 +248,6 @@ export const admitKnowledgeDocumentUpload = defineAuthorizedKnowledgeUseCase({
       knowledgeBaseId: context.knowledgeBaseId,
       knowledgeBaseName: context.knowledgeBase.name,
       workspaceId: context.workspaceId,
-      storageActorUserId: resolveKnowledgeAttributedUserId(principal, context),
     }
   },
 })
@@ -251,16 +257,19 @@ export const uploadKnowledgeDocument = defineAuthorizedKnowledgeUseCase({
   resolveContext: ({ input }: { input: UploadKnowledgeDocumentInput }) =>
     resolveActiveKnowledgeBaseContext(input),
   async execute({ principal, input, context }) {
-    if (input.document.fileSize < 0 || input.document.fileSize > MAX_KNOWLEDGE_DOCUMENT_FILE_SIZE) {
+    if (input.file.fileSize < 0 || input.file.fileSize > MAX_KNOWLEDGE_DOCUMENT_FILE_SIZE) {
       throw new OrchestrationError(
         'payload_too_large',
         'Knowledge document exceeds the 100MB limit'
       )
     }
-    const fileTypeError = validateFileType(input.document.filename, input.document.mimeType)
+    if (input.file.fileSize !== input.file.buffer.byteLength) {
+      throw new Error('Knowledge document upload size does not match its buffered bytes')
+    }
+    const fileTypeError = validateFileType(input.file.filename, input.file.mimeType)
     if (fileTypeError) throw new OrchestrationError('validation', fileTypeError.message)
-    const billingAttribution = await resolveKnowledgeBillingAttribution(principal, context)
     if (input.usageAdmission !== 'pre_admitted') {
+      const billingAttribution = await resolveKnowledgeBillingAttribution(principal, context)
       const usage = await checkAttributedUsageLimits(billingAttribution)
       if (usage.isExceeded) {
         throw new KnowledgeUsageLimitExceededError(
@@ -269,38 +278,71 @@ export const uploadKnowledgeDocument = defineAuthorizedKnowledgeUseCase({
       }
     }
     const requestId = generateRequestId()
-    const uploadedBy = resolveKnowledgeAttributedUserId(principal, context)
+    const storageActorUserId = resolveKnowledgeAttributedUserId(principal, context)
+    const storageKey = generateKnowledgeBaseFileKey(input.file.filename)
+    await recordKnowledgeBaseFileOwnership({
+      key: storageKey,
+      userId: storageActorUserId,
+      workspaceId: context.workspaceId,
+      originalName: input.file.filename,
+      contentType: input.file.mimeType,
+      size: input.file.fileSize,
+    })
+    const storedFile = await StorageService.uploadFile({
+      file: input.file.buffer,
+      fileName: input.file.filename,
+      contentType: input.file.mimeType,
+      context: 'knowledge-base',
+      customKey: storageKey,
+      preserveKey: true,
+      persistMetadata: false,
+    })
+    if (storedFile.key !== storageKey || storedFile.size !== input.file.fileSize) {
+      throw new Error('Knowledge document storage did not preserve the admitted file identity')
+    }
+    if (storedFile.path.includes('?')) {
+      throw new Error('Knowledge document storage returned a path with an unexpected query')
+    }
+
+    const registrationContext = await resolveActiveKnowledgeBaseContext(input)
+    await authorizeWorkspaceOperation(
+      principal,
+      knowledgeOperations.uploadDocument,
+      registrationContext,
+      {
+        delegation: knowledgeDelegationPolicy,
+      }
+    )
+    const billingAttribution = await resolveKnowledgeBillingAttribution(
+      principal,
+      registrationContext
+    )
+    const uploadedBy = resolveKnowledgeAttributedUserId(principal, registrationContext)
+    const documentInput: KnowledgeDocumentInput = {
+      filename: input.file.filename,
+      fileUrl: `${storedFile.path}?context=knowledge-base`,
+      fileSize: input.file.fileSize,
+      mimeType: input.file.mimeType,
+    }
     const document = await createSingleDocument(
-      input.document,
-      context.knowledgeBaseId,
+      documentInput,
+      registrationContext.knowledgeBaseId,
       requestId,
       uploadedBy,
       undefined,
       undefined,
-      { expectedWorkspaceId: context.workspaceId }
-    )
-    if (input.startProcessing !== false) {
-      const processingDocument: DocumentData = {
-        documentId: document.id,
-        filename: document.filename,
-        fileUrl: document.fileUrl,
-        fileSize: document.fileSize,
-        mimeType: document.mimeType,
+      {
+        expectedWorkspaceId: registrationContext.workspaceId,
+        ...(input.startProcessing !== false
+          ? {
+              processing: {
+                processingOptions: input.processingOptions ?? {},
+                billingAttribution,
+              },
+            }
+          : {}),
       }
-      processDocumentsWithQueue(
-        [processingDocument],
-        context.knowledgeBaseId,
-        input.processingOptions ?? {},
-        requestId,
-        billingAttribution
-      ).catch((error: unknown) => {
-        logger.error('Knowledge document processing pipeline failed', {
-          knowledgeBaseId: context.knowledgeBaseId,
-          documentId: document.id,
-          error,
-        })
-      })
-    }
+    )
     return { document, created: true as const }
   },
   projectAudit: ({ input, context, result }) => ({
diff --git a/apps/sim/lib/knowledge/documents/document-processing-source.test.ts b/apps/sim/lib/knowledge/documents/document-processing-source.test.ts
index 4f5379d421f..1a2f7402632 100644
--- a/apps/sim/lib/knowledge/documents/document-processing-source.test.ts
+++ b/apps/sim/lib/knowledge/documents/document-processing-source.test.ts
@@ -228,4 +228,29 @@ describe('knowledge document processing source', () => {
     expect(mockProcessDocument).not.toHaveBeenCalled()
     expect(mockGenerateEmbeddings).not.toHaveBeenCalled()
   })
+
+  it('takes over an existing processing attempt', async () => {
+    dbChainMockFns.limit
+      .mockReset()
+      .mockResolvedValueOnce([{ ...PERSISTED_CONTEXT, processingStatus: 'processing' }])
+      .mockResolvedValueOnce([PERSISTED_PROVENANCE_ROW])
+      .mockResolvedValueOnce([{ id: 'document-1' }])
+    dbChainMockFns.returning.mockReset().mockResolvedValueOnce([])
+
+    await processDocumentAsync('knowledge-base-1', 'document-1', {
+      filename: 'stale.pdf',
+      fileUrl: 'https://example.com/stale.pdf',
+      fileSize: 1,
+      mimeType: 'text/plain',
+    })
+
+    expect(mockProcessDocument).toHaveBeenCalled()
+    expect(mockGenerateEmbeddings).not.toHaveBeenCalled()
+    expect(dbChainMockFns.set).toHaveBeenCalledWith(
+      expect.objectContaining({
+        processingStatus: 'processing',
+        processingStartedAt: expect.any(Date),
+      })
+    )
+  })
 })
diff --git a/apps/sim/lib/knowledge/documents/processing-claim.test.ts b/apps/sim/lib/knowledge/documents/processing-claim.test.ts
new file mode 100644
index 00000000000..6d898f60c40
--- /dev/null
+++ b/apps/sim/lib/knowledge/documents/processing-claim.test.ts
@@ -0,0 +1,129 @@
+/**
+ * @vitest-environment node
+ */
+
+import { dbChainMockFns, resetDbChainMock } from '@sim/testing'
+import { beforeEach, describe, expect, it, vi } from 'vitest'
+import {
+  failStaleDocumentProcessingClaim,
+  KNOWLEDGE_DOCUMENT_PROCESSING_STALE_THRESHOLD_MS,
+  reclaimStaleDocumentProcessingClaim,
+} from '@/lib/knowledge/documents/processing-claim'
+
+const NOW = new Date('2026-08-11T12:00:00.000Z')
+
+describe('reclaimStaleDocumentProcessingClaim', () => {
+  beforeEach(() => {
+    vi.clearAllMocks()
+    resetDbChainMock()
+  })
+
+  it('leaves an active processing claim untouched', async () => {
+    const reclaimed = await reclaimStaleDocumentProcessingClaim({
+      knowledgeBaseId: 'knowledge-base-1',
+      documentId: 'document-1',
+      processingStartedAt: new Date(
+        NOW.getTime() - KNOWLEDGE_DOCUMENT_PROCESSING_STALE_THRESHOLD_MS
+      ),
+      now: NOW,
+    })
+
+    expect(reclaimed).toBe(false)
+    expect(dbChainMockFns.set).not.toHaveBeenCalled()
+  })
+
+  it.each([null, new Date(NOW.getTime() - KNOWLEDGE_DOCUMENT_PROCESSING_STALE_THRESHOLD_MS - 1)])(
+    'reopens an abandoned processing claim started at %s',
+    async (processingStartedAt) => {
+      dbChainMockFns.returning.mockResolvedValueOnce([{ id: 'document-1' }])
+
+      const reclaimed = await reclaimStaleDocumentProcessingClaim({
+        knowledgeBaseId: 'knowledge-base-1',
+        documentId: 'document-1',
+        processingStartedAt,
+        now: NOW,
+      })
+
+      expect(reclaimed).toBe(true)
+      expect(dbChainMockFns.set).toHaveBeenCalledWith({
+        processingStatus: 'pending',
+        processingStartedAt: null,
+        processingCompletedAt: null,
+        processingError: null,
+      })
+    }
+  )
+
+  it('does not report success when the original claim changed before the update', async () => {
+    dbChainMockFns.returning.mockResolvedValueOnce([])
+
+    const reclaimed = await reclaimStaleDocumentProcessingClaim({
+      knowledgeBaseId: 'knowledge-base-1',
+      documentId: 'document-1',
+      processingStartedAt: new Date(
+        NOW.getTime() - KNOWLEDGE_DOCUMENT_PROCESSING_STALE_THRESHOLD_MS - 1
+      ),
+      now: NOW,
+    })
+
+    expect(reclaimed).toBe(false)
+  })
+})
+
+describe('failStaleDocumentProcessingClaim', () => {
+  beforeEach(() => {
+    vi.clearAllMocks()
+    resetDbChainMock()
+  })
+
+  it('rejects an active processing claim', async () => {
+    await expect(
+      failStaleDocumentProcessingClaim({
+        documentId: 'document-1',
+        processingStartedAt: new Date(
+          NOW.getTime() - KNOWLEDGE_DOCUMENT_PROCESSING_STALE_THRESHOLD_MS
+        ),
+        now: NOW,
+      })
+    ).rejects.toThrow('Document has not been processing long enough to be considered dead')
+
+    expect(dbChainMockFns.set).not.toHaveBeenCalled()
+  })
+
+  it('fails the exact abandoned processing claim', async () => {
+    const processingStartedAt = new Date(
+      NOW.getTime() - KNOWLEDGE_DOCUMENT_PROCESSING_STALE_THRESHOLD_MS - 1
+    )
+    dbChainMockFns.returning.mockResolvedValueOnce([{ id: 'document-1' }])
+
+    const result = await failStaleDocumentProcessingClaim({
+      documentId: 'document-1',
+      processingStartedAt,
+      now: NOW,
+    })
+
+    expect(result).toEqual({
+      success: true,
+      processingDuration: KNOWLEDGE_DOCUMENT_PROCESSING_STALE_THRESHOLD_MS + 1,
+    })
+    expect(dbChainMockFns.set).toHaveBeenCalledWith({
+      processingStatus: 'failed',
+      processingError: 'Processing timed out. Please retry or re-sync the connector.',
+      processingCompletedAt: NOW,
+    })
+  })
+
+  it('does not fail a replacement processing claim', async () => {
+    dbChainMockFns.returning.mockResolvedValueOnce([])
+
+    const result = await failStaleDocumentProcessingClaim({
+      documentId: 'document-1',
+      processingStartedAt: new Date(
+        NOW.getTime() - KNOWLEDGE_DOCUMENT_PROCESSING_STALE_THRESHOLD_MS - 1
+      ),
+      now: NOW,
+    })
+
+    expect(result.success).toBe(false)
+  })
+})
diff --git a/apps/sim/lib/knowledge/documents/processing-claim.ts b/apps/sim/lib/knowledge/documents/processing-claim.ts
new file mode 100644
index 00000000000..bfb4a2208c4
--- /dev/null
+++ b/apps/sim/lib/knowledge/documents/processing-claim.ts
@@ -0,0 +1,96 @@
+import { db } from '@sim/db'
+import { document } from '@sim/db/schema'
+import { and, eq, isNull } from 'drizzle-orm'
+
+export const KNOWLEDGE_DOCUMENT_PROCESSING_STALE_THRESHOLD_MS = 10 * 60 * 1000
+
+interface ReclaimStaleDocumentProcessingClaimParams {
+  knowledgeBaseId: string
+  documentId: string
+  processingStartedAt: Date | null
+  now?: Date
+}
+
+interface FailStaleDocumentProcessingClaimParams {
+  documentId: string
+  processingStartedAt: Date
+  now?: Date
+}
+
+/**
+ * Reopens an abandoned processing attempt using its start time as a compare-and-set token.
+ * The former worker's timestamp-guarded writes then cannot commit after the claim is reclaimed.
+ */
+export async function reclaimStaleDocumentProcessingClaim({
+  knowledgeBaseId,
+  documentId,
+  processingStartedAt,
+  now = new Date(),
+}: ReclaimStaleDocumentProcessingClaimParams): Promise<boolean> {
+  if (
+    processingStartedAt &&
+    now.getTime() - processingStartedAt.getTime() <=
+      KNOWLEDGE_DOCUMENT_PROCESSING_STALE_THRESHOLD_MS
+  ) {
+    return false
+  }
+
+  const processingStartedAtGuard = processingStartedAt
+    ? eq(document.processingStartedAt, processingStartedAt)
+    : isNull(document.processingStartedAt)
+  const [reclaimed] = await db
+    .update(document)
+    .set({
+      processingStatus: 'pending',
+      processingStartedAt: null,
+      processingCompletedAt: null,
+      processingError: null,
+    })
+    .where(
+      and(
+        eq(document.id, documentId),
+        eq(document.knowledgeBaseId, knowledgeBaseId),
+        eq(document.processingStatus, 'processing'),
+        processingStartedAtGuard,
+        eq(document.userExcluded, false),
+        isNull(document.archivedAt),
+        isNull(document.deletedAt)
+      )
+    )
+    .returning({ id: document.id })
+
+  return Boolean(reclaimed)
+}
+
+/** Marks only the abandoned processing attempt identified by its start-time token as failed. */
+export async function failStaleDocumentProcessingClaim({
+  documentId,
+  processingStartedAt,
+  now = new Date(),
+}: FailStaleDocumentProcessingClaimParams): Promise<{
+  success: boolean
+  processingDuration: number
+}> {
+  const processingDuration = now.getTime() - processingStartedAt.getTime()
+  if (processingDuration <= KNOWLEDGE_DOCUMENT_PROCESSING_STALE_THRESHOLD_MS) {
+    throw new Error('Document has not been processing long enough to be considered dead')
+  }
+
+  const [failed] = await db
+    .update(document)
+    .set({
+      processingStatus: 'failed',
+      processingError: 'Processing timed out. Please retry or re-sync the connector.',
+      processingCompletedAt: now,
+    })
+    .where(
+      and(
+        eq(document.id, documentId),
+        eq(document.processingStatus, 'processing'),
+        eq(document.processingStartedAt, processingStartedAt)
+      )
+    )
+    .returning({ id: document.id })
+
+  return { success: Boolean(failed), processingDuration }
+}
diff --git a/apps/sim/lib/knowledge/documents/processing-outbox-event.ts b/apps/sim/lib/knowledge/documents/processing-outbox-event.ts
new file mode 100644
index 00000000000..ae893680044
--- /dev/null
+++ b/apps/sim/lib/knowledge/documents/processing-outbox-event.ts
@@ -0,0 +1,21 @@
+import type { db } from '@sim/db'
+import type { BillingAttributionSnapshot } from '@/lib/billing/core/billing-attribution'
+import { enqueueOutboxEvent } from '@/lib/core/outbox/service'
+import type { ProcessingOptions } from '@/lib/knowledge/documents/service'
+
+export const KNOWLEDGE_DOCUMENT_PROCESSING_OUTBOX_EVENT = 'knowledge.document.processing.dispatch'
+
+export interface KnowledgeDocumentProcessingOutboxPayload {
+  knowledgeBaseId: string
+  documentId: string
+  processingOptions: ProcessingOptions
+  billingAttribution: BillingAttributionSnapshot
+}
+
+/** Enqueues durable processing in the same transaction that creates the document. */
+export function enqueueKnowledgeDocumentProcessing(
+  executor: Pick<typeof db, 'insert'>,
+  payload: KnowledgeDocumentProcessingOutboxPayload
+): Promise<string> {
+  return enqueueOutboxEvent(executor, KNOWLEDGE_DOCUMENT_PROCESSING_OUTBOX_EVENT, payload)
+}
diff --git a/apps/sim/lib/knowledge/documents/processing-outbox-handler.test.ts b/apps/sim/lib/knowledge/documents/processing-outbox-handler.test.ts
new file mode 100644
index 00000000000..9e095e9243a
--- /dev/null
+++ b/apps/sim/lib/knowledge/documents/processing-outbox-handler.test.ts
@@ -0,0 +1,181 @@
+/**
+ * @vitest-environment node
+ */
+
+import { beforeEach, describe, expect, it, vi } from 'vitest'
+
+const mocks = vi.hoisted(() => ({
+  getKnowledgeDocument: vi.fn(),
+  processDocumentsWithQueue: vi.fn(),
+  reclaimStaleDocumentProcessingClaim: vi.fn(),
+}))
+
+vi.mock('@/lib/knowledge/documents/service', () => ({
+  getKnowledgeDocument: mocks.getKnowledgeDocument,
+  processDocumentsWithQueue: mocks.processDocumentsWithQueue,
+}))
+
+vi.mock('@/lib/knowledge/documents/processing-claim', () => ({
+  reclaimStaleDocumentProcessingClaim: mocks.reclaimStaleDocumentProcessingClaim,
+}))
+
+import type { BillingAttributionSnapshot } from '@/lib/billing/core/billing-attribution'
+import type { OutboxEventContext } from '@/lib/core/outbox/service'
+import { KNOWLEDGE_DOCUMENT_PROCESSING_OUTBOX_EVENT } from '@/lib/knowledge/documents/processing-outbox-event'
+import { knowledgeDocumentProcessingOutboxHandlers } from '@/lib/knowledge/documents/processing-outbox-handler'
+
+const BILLING_ATTRIBUTION = {
+  actorUserId: 'user-1',
+  workspaceId: 'workspace-1',
+  organizationId: null,
+  billedAccountUserId: 'owner-1',
+  billingEntity: { type: 'user', id: 'owner-1' },
+  billingPeriod: {
+    start: '2026-08-01T00:00:00.000Z',
+    end: '2026-09-01T00:00:00.000Z',
+  },
+  payerSubscription: null,
+} satisfies BillingAttributionSnapshot
+
+const DOCUMENT = {
+  id: 'document-1',
+  filename: 'guide.pdf',
+  fileUrl: '/api/files/serve/kb%2Fguide.pdf?context=knowledge-base',
+  fileSize: 128,
+  mimeType: 'application/pdf',
+  processingStatus: 'pending',
+}
+
+const PAYLOAD = {
+  knowledgeBaseId: 'knowledge-base-1',
+  documentId: 'document-1',
+  processingOptions: { recipe: 'default', lang: 'en' },
+  billingAttribution: BILLING_ATTRIBUTION,
+}
+
+function createContext(eventId = 'outbox-event-1'): OutboxEventContext {
+  return {
+    eventId,
+    eventType: KNOWLEDGE_DOCUMENT_PROCESSING_OUTBOX_EVENT,
+    attempts: 0,
+    maxAttempts: 10,
+    signal: new AbortController().signal,
+    checkpointPayload: vi.fn(),
+  }
+}
+
+function handler() {
+  const value =
+    knowledgeDocumentProcessingOutboxHandlers[KNOWLEDGE_DOCUMENT_PROCESSING_OUTBOX_EVENT]
+  if (!value) throw new Error('Knowledge processing outbox handler is not registered')
+  return value
+}
+
+describe('knowledge document processing outbox handler', () => {
+  beforeEach(() => {
+    vi.clearAllMocks()
+    mocks.getKnowledgeDocument.mockResolvedValue(DOCUMENT)
+    mocks.processDocumentsWithQueue.mockResolvedValue(undefined)
+    mocks.reclaimStaleDocumentProcessingClaim.mockResolvedValue(false)
+  })
+
+  it('dispatches the authoritative document with the stable outbox event id', async () => {
+    await handler()(PAYLOAD, createContext('outbox-event-stable'))
+
+    expect(mocks.getKnowledgeDocument).toHaveBeenCalledWith('knowledge-base-1', 'document-1')
+    expect(mocks.processDocumentsWithQueue).toHaveBeenCalledWith(
+      [
+        {
+          documentId: 'document-1',
+          filename: 'guide.pdf',
+          fileUrl: '/api/files/serve/kb%2Fguide.pdf?context=knowledge-base',
+          fileSize: 128,
+          mimeType: 'application/pdf',
+        },
+      ],
+      'knowledge-base-1',
+      { recipe: 'default', lang: 'en' },
+      'outbox-event-stable',
+      BILLING_ATTRIBUTION
+    )
+  })
+
+  it.each([null, { ...DOCUMENT, processingStatus: 'completed' }])(
+    'completes without redispatch when the document is absent or completed',
+    async (document) => {
+      mocks.getKnowledgeDocument.mockResolvedValueOnce(document)
+
+      await handler()(PAYLOAD, createContext())
+
+      expect(mocks.processDocumentsWithQueue).not.toHaveBeenCalled()
+    }
+  )
+
+  it('keeps the event retryable while an earlier processing attempt is active', async () => {
+    const processingStartedAt = new Date()
+    mocks.getKnowledgeDocument.mockResolvedValueOnce({
+      ...DOCUMENT,
+      processingStatus: 'processing',
+      processingStartedAt,
+    })
+
+    await expect(handler()(PAYLOAD, createContext())).rejects.toThrow(
+      'Knowledge document document-1 is already being processed'
+    )
+
+    expect(mocks.reclaimStaleDocumentProcessingClaim).toHaveBeenCalledWith({
+      knowledgeBaseId: 'knowledge-base-1',
+      documentId: 'document-1',
+      processingStartedAt,
+    })
+    expect(mocks.processDocumentsWithQueue).not.toHaveBeenCalled()
+  })
+
+  it('reclaims and redispatches an abandoned processing attempt', async () => {
+    const processingStartedAt = new Date('2026-08-11T11:00:00.000Z')
+    mocks.getKnowledgeDocument.mockResolvedValueOnce({
+      ...DOCUMENT,
+      processingStatus: 'processing',
+      processingStartedAt,
+    })
+    mocks.reclaimStaleDocumentProcessingClaim.mockResolvedValueOnce(true)
+
+    await handler()(PAYLOAD, createContext('outbox-event-retry'))
+
+    expect(mocks.reclaimStaleDocumentProcessingClaim).toHaveBeenCalledWith({
+      knowledgeBaseId: 'knowledge-base-1',
+      documentId: 'document-1',
+      processingStartedAt,
+    })
+    expect(mocks.processDocumentsWithQueue).toHaveBeenCalledWith(
+      [
+        {
+          documentId: 'document-1',
+          filename: 'guide.pdf',
+          fileUrl: '/api/files/serve/kb%2Fguide.pdf?context=knowledge-base',
+          fileSize: 128,
+          mimeType: 'application/pdf',
+        },
+      ],
+      'knowledge-base-1',
+      { recipe: 'default', lang: 'en' },
+      'outbox-event-retry',
+      BILLING_ATTRIBUTION
+    )
+  })
+
+  it('propagates dispatch failures so the outbox schedules a retry', async () => {
+    const failure = new Error('queue unavailable')
+    mocks.processDocumentsWithQueue.mockRejectedValueOnce(failure)
+
+    await expect(handler()(PAYLOAD, createContext())).rejects.toBe(failure)
+  })
+
+  it('fails fast on malformed durable processing options', async () => {
+    await expect(
+      handler()({ ...PAYLOAD, processingOptions: { unsupported: true } }, createContext())
+    ).rejects.toThrow('unsupported processing options')
+
+    expect(mocks.getKnowledgeDocument).not.toHaveBeenCalled()
+  })
+})
diff --git a/apps/sim/lib/knowledge/documents/processing-outbox-handler.ts b/apps/sim/lib/knowledge/documents/processing-outbox-handler.ts
new file mode 100644
index 00000000000..e148de05d12
--- /dev/null
+++ b/apps/sim/lib/knowledge/documents/processing-outbox-handler.ts
@@ -0,0 +1,94 @@
+import { assertBillingAttributionSnapshot } from '@/lib/billing/core/billing-attribution'
+import type { OutboxHandler, OutboxHandlerRegistry } from '@/lib/core/outbox/service'
+import { reclaimStaleDocumentProcessingClaim } from '@/lib/knowledge/documents/processing-claim'
+import {
+  KNOWLEDGE_DOCUMENT_PROCESSING_OUTBOX_EVENT,
+  type KnowledgeDocumentProcessingOutboxPayload,
+} from '@/lib/knowledge/documents/processing-outbox-event'
+import {
+  getKnowledgeDocument,
+  type ProcessingOptions,
+  processDocumentsWithQueue,
+} from '@/lib/knowledge/documents/service'
+
+function requirePayloadRecord(payload: unknown): Record<string, unknown> {
+  if (!payload || typeof payload !== 'object' || Array.isArray(payload)) {
+    throw new Error('Knowledge document processing outbox payload must be an object')
+  }
+  return payload as Record<string, unknown>
+}
+
+function requireNonEmptyString(value: unknown, field: string): string {
+  if (typeof value !== 'string' || value.trim().length === 0) {
+    throw new Error(`Knowledge document processing outbox payload is missing ${field}`)
+  }
+  return value
+}
+
+function parseProcessingOptions(value: unknown): ProcessingOptions {
+  const record = requirePayloadRecord(value)
+  const unsupported = Object.keys(record).filter((key) => key !== 'recipe' && key !== 'lang')
+  if (unsupported.length > 0) {
+    throw new Error(
+      `Knowledge document processing outbox payload has unsupported processing options: ${unsupported.join(', ')}`
+    )
+  }
+  if (record.recipe !== undefined && typeof record.recipe !== 'string') {
+    throw new Error('Knowledge document processing outbox recipe must be a string')
+  }
+  if (record.lang !== undefined && typeof record.lang !== 'string') {
+    throw new Error('Knowledge document processing outbox lang must be a string')
+  }
+  return {
+    ...(record.recipe !== undefined ? { recipe: record.recipe } : {}),
+    ...(record.lang !== undefined ? { lang: record.lang } : {}),
+  }
+}
+
+function parsePayload(payload: unknown): KnowledgeDocumentProcessingOutboxPayload {
+  const record = requirePayloadRecord(payload)
+  return {
+    knowledgeBaseId: requireNonEmptyString(record.knowledgeBaseId, 'knowledgeBaseId'),
+    documentId: requireNonEmptyString(record.documentId, 'documentId'),
+    processingOptions: parseProcessingOptions(record.processingOptions),
+    billingAttribution: assertBillingAttributionSnapshot(record.billingAttribution),
+  }
+}
+
+const processKnowledgeDocument: OutboxHandler<unknown> = async (rawPayload, context) => {
+  const payload = parsePayload(rawPayload)
+  context.signal.throwIfAborted()
+  const document = await getKnowledgeDocument(payload.knowledgeBaseId, payload.documentId)
+  if (!document || document.processingStatus === 'completed') return
+  if (document.processingStatus === 'processing') {
+    const reclaimed = await reclaimStaleDocumentProcessingClaim({
+      knowledgeBaseId: payload.knowledgeBaseId,
+      documentId: document.id,
+      processingStartedAt: document.processingStartedAt,
+    })
+    if (!reclaimed) {
+      throw new Error(`Knowledge document ${document.id} is already being processed`)
+    }
+  }
+
+  context.signal.throwIfAborted()
+  await processDocumentsWithQueue(
+    [
+      {
+        documentId: document.id,
+        filename: document.filename,
+        fileUrl: document.fileUrl,
+        fileSize: document.fileSize,
+        mimeType: document.mimeType,
+      },
+    ],
+    payload.knowledgeBaseId,
+    payload.processingOptions,
+    context.eventId,
+    payload.billingAttribution
+  )
+}
+
+export const knowledgeDocumentProcessingOutboxHandlers = {
+  [KNOWLEDGE_DOCUMENT_PROCESSING_OUTBOX_EVENT]: processKnowledgeDocument,
+} satisfies OutboxHandlerRegistry
diff --git a/apps/sim/lib/knowledge/documents/service.ts b/apps/sim/lib/knowledge/documents/service.ts
index 5a896d8c9a2..93125c06eb9 100644
--- a/apps/sim/lib/knowledge/documents/service.ts
+++ b/apps/sim/lib/knowledge/documents/service.ts
@@ -64,6 +64,8 @@ import {
   mergeDurableSecretProvenance,
 } from '@/lib/execution/durable-secret-provenance'
 import { processDocument } from '@/lib/knowledge/documents/document-processor'
+import { failStaleDocumentProcessingClaim } from '@/lib/knowledge/documents/processing-claim'
+import { enqueueKnowledgeDocumentProcessing } from '@/lib/knowledge/documents/processing-outbox-event'
 import {
   assertDocumentProcessingBillingContext,
   createDocumentProcessingPayload,
@@ -777,6 +779,7 @@ export async function processDocumentAsync(
   providedBillingContext?: BillingAttributionSnapshot | DocumentProcessingBillingContext
 ): Promise<void> {
   const startTime = Date.now()
+  const processingStartedAt = new Date()
   try {
     logger.info(`[${documentId}] Starting document processing`, {
       knowledgeBaseId,
@@ -859,7 +862,7 @@ export async function processDocumentAsync(
       .update(document)
       .set({
         processingStatus: 'processing',
-        processingStartedAt: new Date(),
+        processingStartedAt,
         processingCompletedAt: null,
         processingError: null,
       })
@@ -934,7 +937,13 @@ export async function processDocumentAsync(
             usageGate.message ?? 'Usage limit exceeded. Please upgrade your plan to continue.',
           processingCompletedAt: new Date(),
         })
-        .where(eq(document.id, documentId))
+        .where(
+          and(
+            eq(document.id, documentId),
+            eq(document.processingStatus, 'processing'),
+            eq(document.processingStartedAt, processingStartedAt)
+          )
+        )
       return
     }
     let billableEmbeddingTokens = 0
@@ -953,6 +962,7 @@ export async function processDocumentAsync(
       currentSourceFileProvenance
     )
 
+    let processingCommitted = false
     await withTimeout(
       runWithKnowledgeModelInputProvenance(
         documentSecretContext.registry,
@@ -1068,7 +1078,7 @@ export async function processDocumentAsync(
             updatedAt: now,
           }))
 
-          await db.transaction(async (tx) => {
+          processingCommitted = await db.transaction(async (tx) => {
             const activeDocument = await tx
               .select({ id: document.id })
               .from(document)
@@ -1076,15 +1086,18 @@ export async function processDocumentAsync(
               .where(
                 and(
                   eq(document.id, documentId),
+                  eq(document.processingStatus, 'processing'),
+                  eq(document.processingStartedAt, processingStartedAt),
                   isNull(document.archivedAt),
                   isNull(document.deletedAt),
                   isNull(knowledgeBase.deletedAt)
                 )
               )
+              .for('update', { of: document })
               .limit(1)
 
             if (activeDocument.length === 0) {
-              return
+              return false
             }
 
             if (embeddingRecords.length > 0) {
@@ -1130,7 +1143,14 @@ export async function processDocumentAsync(
                 processingCompletedAt: now,
                 processingError: null,
               })
-              .where(eq(document.id, documentId))
+              .where(
+                and(
+                  eq(document.id, documentId),
+                  eq(document.processingStatus, 'processing'),
+                  eq(document.processingStartedAt, processingStartedAt)
+                )
+              )
+            return true
           })
         },
         {
@@ -1143,6 +1163,11 @@ export async function processDocumentAsync(
       'Document processing'
     )
 
+    if (!processingCommitted) {
+      logger.info(`[${documentId}] Discarded output from an obsolete processing attempt`)
+      return
+    }
+
     const processingTime = Date.now() - startTime
     logger.info(`[${documentId}] Successfully processed document in ${processingTime}ms`)
 
@@ -1204,7 +1229,13 @@ export async function processDocumentAsync(
         processingError: errorMessage,
         processingCompletedAt: new Date(),
       })
-      .where(eq(document.id, documentId))
+      .where(
+        and(
+          eq(document.id, documentId),
+          eq(document.processingStatus, 'processing'),
+          eq(document.processingStartedAt, processingStartedAt)
+        )
+      )
 
     throw error
   }
@@ -1860,7 +1891,13 @@ export async function createSingleDocument(
   uploadedBy: string | null = null,
   documentId = generateId(),
   secretProvenance?: KnowledgeDocumentWriteSecretProvenance,
-  options?: { expectedWorkspaceId?: string }
+  options?: {
+    expectedWorkspaceId?: string
+    processing?: {
+      processingOptions: ProcessingOptions
+      billingAttribution: BillingAttributionSnapshot
+    }
+  }
 ): Promise<{
   id: string
   knowledgeBaseId: string
@@ -2058,6 +2095,15 @@ export async function createSingleDocument(
       .set({ updatedAt: now })
       .where(eq(knowledgeBase.id, knowledgeBaseId))
 
+    if (options?.processing) {
+      await enqueueKnowledgeDocumentProcessing(tx, {
+        knowledgeBaseId,
+        documentId,
+        processingOptions: options.processing.processingOptions,
+        billingAttribution: options.processing.billingAttribution,
+      })
+    }
+
     return storageNotification
   })
 
@@ -2311,31 +2357,17 @@ export async function markDocumentAsFailedTimeout(
   processingStartedAt: Date,
   requestId: string
 ): Promise<{ success: boolean; processingDuration: number }> {
-  const now = new Date()
-  const processingDuration = now.getTime() - processingStartedAt.getTime()
-  const DEAD_PROCESS_THRESHOLD_MS = 600 * 1000 // 10 minutes
+  const result = await failStaleDocumentProcessingClaim({ documentId, processingStartedAt })
 
-  if (processingDuration <= DEAD_PROCESS_THRESHOLD_MS) {
-    throw new Error('Document has not been processing long enough to be considered dead')
+  if (result.success) {
+    logger.info(
+      `[${requestId}] Marked document ${documentId} as failed due to dead process (processing time: ${Math.round(result.processingDuration / 1000)}s)`
+    )
+  } else {
+    logger.info(`[${requestId}] Did not time out document ${documentId} because its claim changed`)
   }
 
-  await db
-    .update(document)
-    .set({
-      processingStatus: 'failed',
-      processingError: 'Processing timed out. Please retry or re-sync the connector.',
-      processingCompletedAt: now,
-    })
-    .where(eq(document.id, documentId))
-
-  logger.info(
-    `[${requestId}] Marked document ${documentId} as failed due to dead process (processing time: ${Math.round(processingDuration / 1000)}s)`
-  )
-
-  return {
-    success: true,
-    processingDuration,
-  }
+  return result
 }
 
 export async function retryDocumentProcessing(
diff --git a/apps/sim/lib/knowledge/documents/storage-billing.test.ts b/apps/sim/lib/knowledge/documents/storage-billing.test.ts
index 2f0705e3eca..b89971b9f03 100644
--- a/apps/sim/lib/knowledge/documents/storage-billing.test.ts
+++ b/apps/sim/lib/knowledge/documents/storage-billing.test.ts
@@ -13,6 +13,7 @@ const {
   mockMaybeNotifyStorageLimitForBillingContext,
   mockResolveStorageBillingContext,
   mockGetFileMetadataByKeys,
+  mockEnqueueKnowledgeDocumentProcessing,
 } = vi.hoisted(() => ({
   mockApplyStorageUsageDeltasInTx: vi.fn(),
   mockCheckStorageQuota: vi.fn(),
@@ -22,6 +23,7 @@ const {
   mockMaybeNotifyStorageLimitForBillingContext: vi.fn(),
   mockResolveStorageBillingContext: vi.fn(),
   mockGetFileMetadataByKeys: vi.fn(),
+  mockEnqueueKnowledgeDocumentProcessing: vi.fn(),
 }))
 
 vi.mock('@/lib/billing/storage', () => ({
@@ -39,6 +41,10 @@ vi.mock('@/lib/uploads/server/metadata', () => ({
   getFileMetadataByKeys: mockGetFileMetadataByKeys,
 }))
 
+vi.mock('@/lib/knowledge/documents/processing-outbox-event', () => ({
+  enqueueKnowledgeDocumentProcessing: mockEnqueueKnowledgeDocumentProcessing,
+}))
+
 import {
   createDocumentRecords,
   createSingleDocument,
@@ -70,6 +76,7 @@ describe('knowledge document storage attribution', () => {
     mockApplyStorageUsageDeltasInTx.mockResolvedValue(undefined)
     mockMaybeNotifyStorageLimitForBillingContext.mockResolvedValue(undefined)
     mockGetFileMetadataByKeys.mockResolvedValue([])
+    mockEnqueueKnowledgeDocumentProcessing.mockResolvedValue('outbox-1')
   })
 
   it.each(['external-collaborator', 'personal-api-key-user'])(
@@ -167,6 +174,87 @@ describe('knowledge document storage attribution', () => {
     )
   })
 
+  it('enqueues processing inside the document storage transaction', async () => {
+    const billingAttribution = {
+      actorUserId: 'external-collaborator',
+      workspaceId: 'workspace-1',
+      organizationId: null,
+      billedAccountUserId: 'workspace-owner',
+      billingEntity: { type: 'user' as const, id: 'workspace-owner' },
+      billingPeriod: {
+        start: '2026-08-01T00:00:00.000Z',
+        end: '2026-09-01T00:00:00.000Z',
+      },
+      payerSubscription: null,
+    }
+
+    await createSingleDocument(
+      {
+        filename: 'note.txt',
+        fileUrl: 'data:text/plain;base64,SGVsbG8=',
+        fileSize: 5,
+        mimeType: 'text/plain',
+      },
+      'knowledge-base-1',
+      'request-1',
+      'external-collaborator',
+      'document-1',
+      undefined,
+      {
+        expectedWorkspaceId: 'workspace-1',
+        processing: { processingOptions: { lang: 'en' }, billingAttribution },
+      }
+    )
+
+    expect(mockEnqueueKnowledgeDocumentProcessing).toHaveBeenCalledWith(dbChainMock.db, {
+      knowledgeBaseId: 'knowledge-base-1',
+      documentId: 'document-1',
+      processingOptions: { lang: 'en' },
+      billingAttribution,
+    })
+  })
+
+  it('rolls back document creation when durable processing enqueue fails', async () => {
+    const failure = new Error('outbox unavailable')
+    mockEnqueueKnowledgeDocumentProcessing.mockRejectedValueOnce(failure)
+
+    await expect(
+      createSingleDocument(
+        {
+          filename: 'note.txt',
+          fileUrl: 'data:text/plain;base64,SGVsbG8=',
+          fileSize: 5,
+          mimeType: 'text/plain',
+        },
+        'knowledge-base-1',
+        'request-1',
+        'external-collaborator',
+        'document-1',
+        undefined,
+        {
+          expectedWorkspaceId: 'workspace-1',
+          processing: {
+            processingOptions: {},
+            billingAttribution: {
+              actorUserId: 'external-collaborator',
+              workspaceId: 'workspace-1',
+              organizationId: null,
+              billedAccountUserId: 'workspace-owner',
+              billingEntity: { type: 'user', id: 'workspace-owner' },
+              billingPeriod: {
+                start: '2026-08-01T00:00:00.000Z',
+                end: '2026-09-01T00:00:00.000Z',
+              },
+              payerSubscription: null,
+            },
+          },
+        }
+      )
+    ).rejects.toBe(failure)
+
+    expect(mockMaybeNotifyStorageLimitForBillingContext).not.toHaveBeenCalled()
+  })
+
   it.each(['kb', 'knowledge-base'])(
     'uses server-known %s file metadata size for quota, ledger, and document row',
     async (keyPrefix) => {
diff --git a/apps/sim/lib/knowledge/orchestration/documents.test.ts b/apps/sim/lib/knowledge/orchestration/documents.test.ts
index e4a66fec7f7..aef8d2eafca 100644
--- a/apps/sim/lib/knowledge/orchestration/documents.test.ts
+++ b/apps/sim/lib/knowledge/orchestration/documents.test.ts
@@ -378,7 +378,13 @@ describe('performDeleteKnowledgeDocument', () => {
 })
 
 describe('document processing state changes', () => {
-  beforeEach(() => vi.clearAllMocks())
+  beforeEach(() => {
+    vi.clearAllMocks()
+    mockMarkDocumentAsFailedTimeout.mockResolvedValue({
+      success: true,
+      processingDuration: 600_001,
+    })
+  })
 
   it('refuses to time out a document that is not processing', async () => {
     const outcome = await performMarkKnowledgeDocumentTimedOut({
@@ -409,6 +415,19 @@ describe('document processing state changes', () => {
     expect(outcome).toMatchObject({ success: false, errorCode: 'validation' })
   })
 
+  it('reports a conflict when the processing claim changes before the timeout write', async () => {
+    mockMarkDocumentAsFailedTimeout.mockResolvedValue({
+      success: false,
+      processingDuration: 600_001,
+    })
+
+    const outcome = await performMarkKnowledgeDocumentTimedOut({
+      document: { id: 'doc-1', processingStatus: 'processing', processingStartedAt: new Date() },
+    })
+
+    expect(outcome).toMatchObject({ success: false, errorCode: 'conflict' })
+  })
+
   it('refuses to retry a document that has not failed', async () => {
     const outcome = await performRetryKnowledgeDocumentProcessing({
       knowledgeBaseId: 'kb-1',
diff --git a/apps/sim/lib/knowledge/orchestration/documents.ts b/apps/sim/lib/knowledge/orchestration/documents.ts
index 72c7eb51cf7..60d1d8758e2 100644
--- a/apps/sim/lib/knowledge/orchestration/documents.ts
+++ b/apps/sim/lib/knowledge/orchestration/documents.ts
@@ -527,7 +527,17 @@ export async function performMarkKnowledgeDocumentTimedOut(
   }
 
   try {
-    await markDocumentAsFailedTimeout(document.id, document.processingStartedAt, requestId)
+    const result = await markDocumentAsFailedTimeout(
+      document.id,
+      document.processingStartedAt,
+      requestId
+    )
+    if (!result.success) {
+      return fail(
+        'Document processing attempt changed before timeout could be recorded',
+        'conflict'
+      )
+    }
   } catch (error) {
     // The service rejects a document that has not been processing long enough
     // to be presumed dead; that is a caller-fixable "try again later", not a fault.