@@ -1,4 +1,8 @@
 /** Real PostgreSQL content admission, pagination, captured metadata, and streamed ZIP readback. */
+import { mkdtempSync } from 'node:fs'
+import { rm } from 'node:fs/promises'
+import { tmpdir } from 'node:os'
+import path from 'node:path'
 import * as audit from '@sim/audit'
 import { db } from '@sim/db'
 import {
@@ -18,6 +22,14 @@ import { eq, inArray } from 'drizzle-orm'
 import { PostgresJsPreparedQuery } from 'drizzle-orm/postgres-js/session'
 import JSZip from 'jszip'
 import { afterAll, afterEach, beforeAll, describe, expect, it, vi } from 'vitest'
+
+const fixtureStorage = vi.hoisted(() => ({ root: '' }))
+vi.mock('@/lib/uploads/core/setup.server', () => ({
+  get UPLOAD_DIR_SERVER() {
+    return fixtureStorage.root
+  },
+}))
+
 import { observeContentDelivery } from '@/lib/core/application'
 import { encryptSecret } from '@/lib/core/security/encryption'
 import type { DurableSecretProvenance } from '@/lib/execution/durable-secret-provenance'
@@ -28,11 +40,13 @@ import {
 import { admitKnowledgeChunks } from '@/lib/knowledge/application/admit-knowledge-content'
 import { KNOWLEDGE_DELEGATION_AUDIENCE } from '@/lib/knowledge/application/authorization'
 import { listKnowledgeChunks } from '@/lib/knowledge/application/chunks'
+import * as knowledgeContexts from '@/lib/knowledge/application/contexts'
 import { listKnowledgeDocuments } from '@/lib/knowledge/application/documents'
 import {
   exportKnowledgeBase,
   type KnowledgeBaseExportBundle,
 } from '@/lib/knowledge/application/exports'
+import { readOriginalKnowledgeDocument } from '@/lib/knowledge/application/read-original-document'
 import {
   readDetailedKnowledgeTagUsage,
   readKnowledgeTagUsage,
@@ -48,6 +62,7 @@ import { buildKnowledgeBundleArchive } from '@/lib/knowledge/transfer/export-arc
 import { embeddingVectorValues } from '@/lib/knowledge/vector-columns'
 import { createCopilotChatPrincipal } from '@/lib/mothership/auth/application-delegation'
 import { createRegistryContentGate } from '@/lib/mothership/content-delivery/registry-gate'
+import { uploadFile } from '@/lib/uploads/core/storage-service'
 import { ResolvedSecretTraceRegistry } from '@/executor/utils/resolved-secret-trace-registry'
 
 const SECRET = 'fixture-knowledge-token-41875'
@@ -173,6 +188,7 @@ async function drainAudits() {
 }
 
 beforeAll(async () => {
+  fixtureStorage.root = mkdtempSync(path.join(tmpdir(), 'sim-knowledge-delivery-'))
   await seedKnowledgeAclFixture(ids)
   const record = audit.recordAudit
   vi.spyOn(audit, 'recordAudit').mockImplementation((entry) => {
@@ -208,6 +224,7 @@ afterAll(async () => {
   await deleteWorkspaceFixture(db, eq(workspace.id, ids.workspaceId))
   await db.delete(organization).where(eq(organization.id, ids.organizationId))
   await db.delete(user).where(inArray(user.id, [ids.aliceId, ids.bobId]))
+  await rm(fixtureStorage.root, { recursive: true, force: true })
   await db.$client.end()
 })
 
@@ -444,6 +461,68 @@ describe('knowledge content delivery', () => {
     }
   )
 
+  it('binds an original read to the captured storage key across a concurrent replacement', async () => {
+    const doc = await seedDocument({ original: false, content: SECRET, provenance: exact })
+    const oldKey = `kb/${generateId()}.txt`
+    const newKey = `kb/${generateId()}.txt`
+    for (const [key, content] of [
+      [oldKey, SECRET],
+      [newKey, 'replacement public content'],
+    ]) {
+      await uploadFile({
+        file: Buffer.from(content),
+        fileName: 'fixture.txt',
+        contentType: 'text/plain',
+        context: 'knowledge-base',
+        customKey: key,
+        preserveKey: true,
+        persistMetadata: false,
+      })
+    }
+    await db.update(document).set({ storageKey: oldKey }).where(eq(document.id, doc.id))
+    const input = {
+      knowledgeBaseId: ids.knowledgeBaseId,
+      documentId: doc.id,
+      assertedWorkspaceId: ids.workspaceId,
+    }
+    const matched = await inChat(() => readOriginalKnowledgeDocument.execute({ principal, input }))
+    expect(matched.buffer?.toString()).toBe(SECRET)
+    expect(matched.hasRecordedSecrets).toBe(true)
+    const resolve = knowledgeContexts.resolveCanonicalActiveKnowledgeDocumentContext
+    let replaced = false
+    const interleave = vi
+      .spyOn(knowledgeContexts, 'resolveCanonicalActiveKnowledgeDocumentContext')
+      .mockImplementation(async (...args) => {
+        const context = await resolve(...args)
+        await db.transaction(async (tx) => {
+          const [row] = await tx
+            .update(document)
+            .set({ storageKey: newKey })
+            .where(eq(document.id, doc.id))
+            .returning()
+          await replaceKnowledgeDocumentSecretProvenanceInTx(
+            tx,
+            doc.id,
+            createKnowledgeDocumentSourceValue(row),
+            { status: 'exact', entries: [] }
+          )
+        })
+        replaced = true
+        return context
+      })
+    try {
+      await expect(
+        inChat(() => readOriginalKnowledgeDocument.execute({ principal, input }))
+      ).rejects.toThrow(/provenance|model/i)
+      expect(replaced).toBe(true)
+    } finally {
+      interleave.mockRestore()
+    }
+    const current = await inChat(() => readOriginalKnowledgeDocument.execute({ principal, input }))
+    expect(current.buffer?.toString()).toBe('replacement public content')
+    expect(current.hasRecordedSecrets).toBe(false)
+  })
+
   it('exports clean and legacy originals with chunks through the existing ZIP stream', async () => {
     const docs = [
       await seedDocument(),
 
@@ -89,6 +89,7 @@ describe('original knowledge document read', () => {
     )
     workspaceAuthzMockFns.mockResolveEffectiveWorkspacePermission.mockResolvedValue('read')
     mocks.provenance.mockResolvedValue({
+      storageKey: document.storageKey,
       source: { filename: document.filename, fileUrl: document.fileUrl },
       provenance: { status: 'exact', entries: [] },
     })
@@ -104,6 +105,7 @@ describe('original knowledge document read', () => {
       },
     })
     mocks.provenance.mockResolvedValue({
+      storageKey: document.storageKey,
       source: { filename: document.filename, fileUrl: 'https://example.test/private' },
       provenance: { status: 'exact', entries: [] },
     })
@@ -144,6 +146,7 @@ describe('original knowledge document read', () => {
     'refuses Chat an original its gate refuses, before reading it: %j',
     async (provenance) => {
       mocks.provenance.mockResolvedValue({
+        storageKey: document.storageKey,
         source: { filename: document.filename, fileUrl: document.fileUrl },
         provenance,
       })
@@ -156,6 +159,7 @@ describe('original knowledge document read', () => {
   })
   it('classifies a concurrent source replacement as unknown, refusing it before reading', async () => {
     mocks.provenance.mockResolvedValue({
+      storageKey: document.storageKey,
       source: { filename: 'changed', fileUrl: document.fileUrl },
       provenance: { status: 'exact', entries: [] },
     })
@@ -164,6 +168,7 @@ describe('original knowledge document read', () => {
   })
   it('reads for a caller outside Chat without classifying, flagging recorded secrets', async () => {
     mocks.provenance.mockResolvedValue({
+      storageKey: document.storageKey,
       source: { filename: document.filename, fileUrl: document.fileUrl },
       provenance: { status: 'exact', entries: [{ secret: 'private' }] },
     })
 
@@ -53,8 +53,9 @@ export const readOriginalKnowledgeDocument = defineAuthorizedKnowledgeUseCase({
       )
     const snapshot = await loadKnowledgeDocumentDurableSecretProvenance(doc.id)
     const provenance =
+      snapshot.storageKey === doc.storageKey &&
       hashDurableSecretProvenanceValue(snapshot.source) ===
-      hashDurableSecretProvenanceValue(createKnowledgeDocumentSourceValue(doc))
+        hashDurableSecretProvenanceValue(createKnowledgeDocumentSourceValue(doc))
         ? snapshot.provenance
         : ({ status: 'unknown' } as const)
     await requireAdmittedContent(principal, {
 
@@ -103,6 +103,7 @@ import {
   userTableRowSecretProvenance,
   workflowTest,
   workspaceFileSearchRevision,
+  workspaceFiles,
 } from '@sim/db/schema'
 import { sha256Hex } from '@sim/security/hash'
 import { eq, sql } from 'drizzle-orm'
@@ -210,11 +211,18 @@ function noteExercised(method: string, route: string) {
 }
 
 describe('content reaching Chat is admitted per item', () => {
+  let redis: NonNullable<ReturnType<typeof getRedisClient>>
   let fixture: ContentFixture
   let connector: { connectorId: string; documentId: string }
 
   beforeAll(async () => {
     fixtureStorage.root = mkdtempSync(path.join(tmpdir(), 'sim-content-delivery-'))
+    const client = getRedisClient()
+    if (!client)
+      throw new Error(
+        'Set TEST_REDIS_URL to a disposable local Redis or use bun run test:integration'
+      )
+    redis = client
     // Compile the lazy tool graph before request deadlines and per-case provider fixtures exist.
     await matchV2Route('/api/v2/tools/file_get_content/execute')?.load()
     fixture = await seedContentFixture()
@@ -273,7 +281,7 @@ describe('content reaching Chat is admitted per item', () => {
       workspaceId: fixture.ids.workspaceId,
       type: 'mothership',
     })
-    await getRedisClient()?.set(
+    await redis.set(
       `mothership:sandbox-resources:${token}:context`,
       JSON.stringify({
         toolCallId: generateId(),
@@ -608,6 +616,51 @@ describe('content reaching Chat is admitted per item', () => {
       expect(refused.body).not.toContain('gamma')
     })
 
+    it.each(['clean', 'entries'] as const)(
+      'applies the archive declared-size budget after %s contributor admission',
+      async (kind) => {
+        const input = await getWorkspaceFile(ws(), fixture.files[kind], { throwOnError: true })
+        if (!input) throw new Error('Missing archive contributor fixture')
+        const source = `await getFileBase64('${input.id}'); pdf.addPage().drawText('fixture render');`
+        const documentIds: string[] = []
+        for (let index = 0; index < (kind === 'clean' ? 6 : 5); index += 1) {
+          const doc = await uploadWorkspaceFile(
+            ws(),
+            fixture.ids.aliceId,
+            Buffer.from(
+              index === 5 ? 'throw new Error("archive budget checked too late")' : source
+            ),
+            `archive-budget-${generateId()}.pdf`,
+            'text/x-python-pdf',
+            {
+              notifyWorkspaceChange: false,
+              secretProvenance: { status: 'exact', entries: [] },
+            }
+          )
+          // Declared source sizes exercise aggregate accounting without large fixture allocations.
+          await db
+            .update(workspaceFiles)
+            .set({ sizeBytes: 50 * 1024 * 1024 })
+            .where(eq(workspaceFiles.id, doc.id))
+          documentIds.push(doc.id)
+        }
+        const result = await cli(
+          'GET',
+          `/api/v2/files/bulk-download?workspaceId=${ws()}&fileIds=${fixture.files.clean},${documentIds}`
+        )
+        if (kind === 'clean') {
+          expect(result.status, result.body).toBe(400)
+          expect(result.body).toMatch(/download limit/i)
+        } else {
+          expect(result.status, result.body).toBe(200)
+          expect(result.body).toContain(CANARY.clean)
+          expect(result.body).toContain('sim-download-report.json')
+          for (const id of documentIds) expect(result.body).toContain(id)
+          expect(result.body).not.toContain('%PDF-1.7')
+        }
+      }
+    )
+
     it('shares only clean files publicly on Chat’s behalf (#9, D1)', async () => {
       const share = (fileId: string) =>
         cli('PATCH', `/api/v2/files/${fileId}/share`, {
 
@@ -31,7 +31,7 @@ import { fileOperations } from '@/lib/workspace-files/application/operations'
 import { parseWorkspaceFileFolderDisplayPath } from '@/lib/workspace-files/folder-display-path'
 import { MAX_ZIP_DOWNLOAD_FILES } from '@/lib/workspace-files/limits'
 
-export const MAX_ZIP_DOWNLOAD_BYTES = 250 * 1024 * 1024
+const MAX_ZIP_DOWNLOAD_BYTES = 250 * 1024 * 1024
 const MAX_REQUESTED_FILE_IDS = 1_000
 const MAX_REQUESTED_FOLDER_IDS = 1_000
 
@@ -104,6 +104,14 @@ function validationError(message: string): never {
   throw new OrchestrationError('validation', message)
 }
 
+function validateDeclaredBytes(bytes: number): void {
+  if (bytes > MAX_ZIP_DOWNLOAD_BYTES) {
+    validationError(
+      `Selected files total ${formatFileSize(bytes)}, which exceeds the ${formatFileSize(MAX_ZIP_DOWNLOAD_BYTES)} download limit.`
+    )
+  }
+}
+
 async function executeDownloadWorkspaceFileItems({
   input,
   context,
@@ -183,16 +191,11 @@ async function executeDownloadWorkspaceFileItems({
     'opaque'
   )
 
-  const declaredBytes = filesToZip.reduce((sum, file) => sum + file.size, 0)
-  if (declaredBytes > MAX_ZIP_DOWNLOAD_BYTES) {
-    validationError(
-      `Selected files total ${formatFileSize(declaredBytes)}, which exceeds the ${formatFileSize(MAX_ZIP_DOWNLOAD_BYTES)} download limit.`
-    )
-  }
-
   const reservedForStreamed = filesToZip
     .filter((file) => !needsRenderedArtifact(file.type, file.name))
     .reduce((sum, file) => sum + file.size, 0)
+  let declaredBytes = reservedForStreamed
+  validateDeclaredBytes(declaredBytes)
   const renderedDocuments = new Map<string, Buffer>()
   const pendingNames: string[] = []
   let renderedBytes = 0
@@ -211,6 +214,8 @@ async function executeDownloadWorkspaceFileItems({
         filesToZip = filesToZip.filter((admitted) => admitted.id !== file.id)
         continue
       }
+      declaredBytes += file.size
+      validateDeclaredBytes(declaredBytes)
       renderedBytes += buffer.length
       renderedDocuments.set(file.id, buffer)
     } catch (error) {
@@ -240,7 +245,7 @@ async function executeDownloadWorkspaceFileItems({
     folderPaths,
     renderedDocuments,
     /** Counted over what is zipped, after any rendered document whose contributors were refused. */
-    declaredBytes: filesToZip.reduce((sum, file) => sum + file.size, 0),
+    declaredBytes,
   }
 }
 
 
@@ -5280,7 +5280,6 @@
   "apps/sim/lib/workspace-events/constants.ts#SIM_RULE_EVENT_TYPES",
   "apps/sim/lib/workspace-files/application/csv-preview-workspace-file.ts#CsvPreviewWorkspaceFileInput",
   "apps/sim/lib/workspace-files/application/delete-workspace-file.ts#DeleteWorkspaceFileInput",
-  "apps/sim/lib/workspace-files/application/download-workspace-file-items.ts#MAX_ZIP_DOWNLOAD_BYTES",
   "apps/sim/lib/workspace-files/application/download-workspace-file.ts#DownloadWorkspaceFileInput",
   "apps/sim/lib/workspace-files/application/extract-workspace-file.ts#ExtractWorkspaceFileInput",
   "apps/sim/lib/workspace-files/application/extract-workspace-file.ts#ExtractWorkspaceFileResult",