diff --git a/apps/sim/app/api/files/presigned/batch/route.test.ts b/apps/sim/app/api/files/presigned/batch/route.test.ts
new file mode 100644
index 00000000000..988fae9cce4
--- /dev/null
+++ b/apps/sim/app/api/files/presigned/batch/route.test.ts
@@ -0,0 +1,189 @@
+/**
+ * Tests for the batch presigned upload API route
+ *
+ * @vitest-environment node
+ */
+
+import { authMockFns, storageServiceMock, storageServiceMockFns } from '@sim/testing'
+import { NextRequest } from 'next/server'
+import { beforeEach, describe, expect, it, vi } from 'vitest'
+
+const {
+  mockValidateFileType,
+  mockGetUserEntityPermissions,
+  mockRecordKnowledgeBaseFileOwnershipMany,
+} = vi.hoisted(() => ({
+  mockValidateFileType: vi.fn().mockReturnValue(null),
+  mockGetUserEntityPermissions: vi.fn().mockResolvedValue('write'),
+  mockRecordKnowledgeBaseFileOwnershipMany: vi.fn().mockResolvedValue(undefined),
+}))
+
+vi.mock('@/lib/uploads/config', () => ({
+  getServeStoragePrefix: () => 's3',
+}))
+
+vi.mock('@/lib/uploads/core/storage-service', () => storageServiceMock)
+
+vi.mock('@/lib/uploads/utils/validation', () => ({
+  validateFileType: mockValidateFileType,
+  SUPPORTED_ARCHIVE_EXTENSIONS: ['zip'] as const,
+}))
+
+vi.mock('@/lib/workspaces/permissions/utils', () => ({
+  getUserEntityPermissions: mockGetUserEntityPermissions,
+}))
+
+vi.mock('@/lib/uploads/server/metadata', () => ({
+  recordKnowledgeBaseFileOwnershipMany: mockRecordKnowledgeBaseFileOwnershipMany,
+}))
+
+import { POST } from '@/app/api/files/presigned/batch/route'
+
+const KB_QUERY = 'type=knowledge-base&workspaceId=ws-1'
+
+const buildRequest = (query: string, files?: unknown) =>
+  new NextRequest(`http://localhost:3000/api/files/presigned/batch?${query}`, {
+    method: 'POST',
+    body: JSON.stringify({
+      files: files ?? [{ fileName: 'doc.pdf', contentType: 'application/pdf', fileSize: 1024 }],
+    }),
+  })
+
+describe('/api/files/presigned/batch', () => {
+  beforeEach(() => {
+    vi.clearAllMocks()
+    authMockFns.mockGetSession.mockResolvedValue({ user: { id: 'user-1' } })
+    mockValidateFileType.mockReturnValue(null)
+    mockGetUserEntityPermissions.mockResolvedValue('write')
+    mockRecordKnowledgeBaseFileOwnershipMany.mockResolvedValue(undefined)
+    storageServiceMockFns.mockHasCloudStorage.mockReturnValue(true)
+    storageServiceMockFns.mockGenerateBatchPresignedUploadUrls.mockImplementation(
+      async (files: Array<{ fileName: string }>, context: string) =>
+        files.map((file) => ({
+          url: `https://example.com/${context}/${file.fileName}`,
+          key: `${context}/${file.fileName}`,
+        }))
+    )
+  })
+
+  it('returns 401 when the caller has no session', async () => {
+    authMockFns.mockGetSession.mockResolvedValue(null)
+
+    const response = await POST(buildRequest(KB_QUERY))
+
+    expect(response.status).toBe(401)
+    expect(storageServiceMockFns.mockGenerateBatchPresignedUploadUrls).not.toHaveBeenCalled()
+  })
+
+  it.each([
+    'workspace-logos',
+    'profile-pictures',
+    'execution',
+    'mothership',
+    'chat',
+    'copilot',
+    'workspace',
+  ])('refuses to presign the %s context', async (type) => {
+    const response = await POST(buildRequest(`type=${type}&workspaceId=ws-1`))
+    const data = await response.json()
+
+    expect(response.status).toBe(400)
+    expect(data.error).toContain('Invalid type parameter')
+    expect(storageServiceMockFns.mockGenerateBatchPresignedUploadUrls).not.toHaveBeenCalled()
+  })
+
+  it('returns 400 when type is missing', async () => {
+    const response = await POST(buildRequest('workspaceId=ws-1'))
+
+    expect(response.status).toBe(400)
+    expect(storageServiceMockFns.mockGenerateBatchPresignedUploadUrls).not.toHaveBeenCalled()
+  })
+
+  it('returns 400 when workspaceId is missing', async () => {
+    const response = await POST(buildRequest('type=knowledge-base'))
+    const data = await response.json()
+
+    expect(response.status).toBe(400)
+    expect(data.error).toContain('workspaceId')
+    expect(mockGetUserEntityPermissions).not.toHaveBeenCalled()
+    expect(storageServiceMockFns.mockGenerateBatchPresignedUploadUrls).not.toHaveBeenCalled()
+  })
+
+  it.each([['read'], [null]])(
+    'returns 403 when the caller has %s access to the workspace',
+    async (permission) => {
+      mockGetUserEntityPermissions.mockResolvedValue(permission)
+
+      const response = await POST(buildRequest(KB_QUERY))
+
+      expect(response.status).toBe(403)
+      expect(storageServiceMockFns.mockGenerateBatchPresignedUploadUrls).not.toHaveBeenCalled()
+    }
+  )
+
+  it('authorizes the workspace before returning the local-storage fallback', async () => {
+    storageServiceMockFns.mockHasCloudStorage.mockReturnValue(false)
+    mockGetUserEntityPermissions.mockResolvedValue('read')
+
+    const response = await POST(buildRequest(KB_QUERY))
+
+    expect(response.status).toBe(403)
+  })
+
+  it('rejects unsupported file types before minting any URL', async () => {
+    mockValidateFileType.mockReturnValue({
+      code: 'UNSUPPORTED_FILE_TYPE',
+      message: 'Unsupported file type: html.',
+      supportedTypes: ['pdf'],
+    })
+
+    const response = await POST(
+      buildRequest(KB_QUERY, [{ fileName: 'poc.html', contentType: 'text/html', fileSize: 41 }])
+    )
+    const data = await response.json()
+
+    expect(response.status).toBe(400)
+    expect(data.code).toBe('UNSUPPORTED_FILE_TYPE')
+    expect(storageServiceMockFns.mockGenerateBatchPresignedUploadUrls).not.toHaveBeenCalled()
+  })
+
+  it('mints knowledge-base URLs and records workspace ownership for a permitted caller', async () => {
+    const response = await POST(buildRequest(KB_QUERY))
+    const data = await response.json()
+
+    expect(response.status).toBe(200)
+    expect(mockGetUserEntityPermissions).toHaveBeenCalledWith('user-1', 'workspace', 'ws-1')
+    expect(storageServiceMockFns.mockGenerateBatchPresignedUploadUrls).toHaveBeenCalledWith(
+      [{ fileName: 'doc.pdf', contentType: 'application/pdf', fileSize: 1024 }],
+      'knowledge-base',
+      'user-1',
+      3600
+    )
+    expect(data.files).toHaveLength(1)
+    expect(data.files[0].fileInfo.key).toBe('knowledge-base/doc.pdf')
+    expect(data.files[0].fileInfo.path).toContain('?context=knowledge-base')
+    expect(data.directUploadSupported).toBe(true)
+    expect(mockRecordKnowledgeBaseFileOwnershipMany).toHaveBeenCalledWith([
+      {
+        key: 'knowledge-base/doc.pdf',
+        userId: 'user-1',
+        workspaceId: 'ws-1',
+        originalName: 'doc.pdf',
+        contentType: 'application/pdf',
+        size: 1024,
+      },
+    ])
+  })
+
+  it('returns the fallback response when cloud storage is not configured', async () => {
+    storageServiceMockFns.mockHasCloudStorage.mockReturnValue(false)
+
+    const response = await POST(buildRequest(KB_QUERY))
+    const data = await response.json()
+
+    expect(response.status).toBe(200)
+    expect(data.directUploadSupported).toBe(false)
+    expect(data.files[0].presignedUrl).toBe('')
+    expect(storageServiceMockFns.mockGenerateBatchPresignedUploadUrls).not.toHaveBeenCalled()
+  })
+})
diff --git a/apps/sim/app/api/files/presigned/batch/route.ts b/apps/sim/app/api/files/presigned/batch/route.ts
index 85dfb85ec08..226fdc9ed87 100644
--- a/apps/sim/app/api/files/presigned/batch/route.ts
+++ b/apps/sim/app/api/files/presigned/batch/route.ts
@@ -2,12 +2,12 @@ import { createLogger } from '@sim/logger'
 import { type NextRequest, NextResponse } from 'next/server'
 import {
   batchPresignedUploadBodyContract,
-  uploadTypeSchema,
+  batchPresignedUploadTypeSchema,
+  batchPresignedUploadTypes,
 } from '@/lib/api/contracts/storage-transfer'
 import { getValidationErrorMessage, parseRequest } from '@/lib/api/server'
 import { getSession } from '@/lib/auth'
 import { withRouteHandler } from '@/lib/core/utils/with-route-handler'
-import type { StorageContext } from '@/lib/uploads/config'
 import { getServeStoragePrefix } from '@/lib/uploads/config'
 import {
   generateBatchPresignedUploadUrls,
@@ -20,8 +20,13 @@ import { createErrorResponse } from '@/app/api/files/utils'
 
 const logger = createLogger('BatchPresignedUploadAPI')
 
-const VALID_UPLOAD_TYPES = ['knowledge-base', 'chat', 'copilot', 'profile-pictures'] as const
-
+/**
+ * Mints presigned upload URLs for knowledge-base ingest, the only context this
+ * endpoint can authorize. Every request must name a workspace the caller has
+ * write access to; other storage contexts are rejected rather than presigned,
+ * because a presigned PUT is a write grant into a bucket served from a trusted
+ * origin.
+ */
 export const POST = withRouteHandler(async (request: NextRequest) => {
   try {
     const session = await getSession()
@@ -52,59 +57,46 @@ export const POST = withRouteHandler(async (request: NextRequest) => {
       return NextResponse.json({ error: 'type query parameter is required' }, { status: 400 })
     }
 
-    const uploadTypeResult = uploadTypeSchema.safeParse(uploadTypeParam)
+    const uploadTypeResult = batchPresignedUploadTypeSchema.safeParse(uploadTypeParam)
     if (!uploadTypeResult.success) {
       return NextResponse.json(
-        { error: `Invalid type parameter. Must be one of: ${VALID_UPLOAD_TYPES.join(', ')}` },
+        {
+          error: `Invalid type parameter. Must be one of: ${batchPresignedUploadTypes.join(', ')}`,
+        },
         { status: 400 }
       )
     }
 
-    const uploadType = uploadTypeResult.data as StorageContext
-
+    const uploadType = uploadTypeResult.data
     const sessionUserId = session.user.id
 
-    let knowledgeBaseWorkspaceId: string | null = null
-    if (uploadType === 'knowledge-base') {
-      for (const file of files) {
-        const fileValidationError = validateFileType(file.fileName, file.contentType)
-        if (fileValidationError) {
-          return NextResponse.json(
-            {
-              error: fileValidationError.message,
-              code: fileValidationError.code,
-              supportedTypes: fileValidationError.supportedTypes,
-            },
-            { status: 400 }
-          )
-        }
-      }
-
-      knowledgeBaseWorkspaceId = request.nextUrl.searchParams.get('workspaceId')
-      if (!knowledgeBaseWorkspaceId?.trim()) {
+    for (const file of files) {
+      const fileValidationError = validateFileType(file.fileName, file.contentType)
+      if (fileValidationError) {
         return NextResponse.json(
-          { error: 'workspaceId query parameter is required for knowledge-base uploads' },
+          {
+            error: fileValidationError.message,
+            code: fileValidationError.code,
+            supportedTypes: fileValidationError.supportedTypes,
+          },
           { status: 400 }
         )
       }
+    }
 
-      const permission = await getUserEntityPermissions(
-        sessionUserId,
-        'workspace',
-        knowledgeBaseWorkspaceId
+    const workspaceId = request.nextUrl.searchParams.get('workspaceId')
+    if (!workspaceId?.trim()) {
+      return NextResponse.json(
+        { error: 'workspaceId query parameter is required for knowledge-base uploads' },
+        { status: 400 }
       )
-      if (permission !== 'write' && permission !== 'admin') {
-        return NextResponse.json(
-          { error: 'Write or Admin access required for knowledge-base uploads' },
-          { status: 403 }
-        )
-      }
     }
 
-    if (uploadType === 'copilot' && !sessionUserId?.trim()) {
+    const permission = await getUserEntityPermissions(sessionUserId, 'workspace', workspaceId)
+    if (permission !== 'write' && permission !== 'admin') {
       return NextResponse.json(
-        { error: 'Authenticated user session is required for copilot uploads' },
-        { status: 400 }
+        { error: 'Write or Admin access required for knowledge-base uploads' },
+        { status: 403 }
       )
     }
 
@@ -149,19 +141,16 @@ export const POST = withRouteHandler(async (request: NextRequest) => {
       `Generated ${files.length} presigned URLs in ${duration}ms (avg ${Math.round(duration / files.length)}ms per file)`
     )
 
-    if (uploadType === 'knowledge-base' && knowledgeBaseWorkspaceId) {
-      const ownerWorkspaceId = knowledgeBaseWorkspaceId
-      await recordKnowledgeBaseFileOwnershipMany(
-        presignedUrls.map((urlResponse, index) => ({
-          key: urlResponse.key,
-          userId: sessionUserId,
-          workspaceId: ownerWorkspaceId,
-          originalName: files[index].fileName,
-          contentType: files[index].contentType,
-          size: files[index].fileSize,
-        }))
-      )
-    }
+    await recordKnowledgeBaseFileOwnershipMany(
+      presignedUrls.map((urlResponse, index) => ({
+        key: urlResponse.key,
+        userId: sessionUserId,
+        workspaceId,
+        originalName: files[index].fileName,
+        contentType: files[index].contentType,
+        size: files[index].fileSize,
+      }))
+    )
 
     const storagePrefix = getServeStoragePrefix()
 
diff --git a/apps/sim/app/api/files/presigned/route.test.ts b/apps/sim/app/api/files/presigned/route.test.ts
index c3e756620ca..3674ac70b76 100644
--- a/apps/sim/app/api/files/presigned/route.test.ts
+++ b/apps/sim/app/api/files/presigned/route.test.ts
@@ -220,14 +220,17 @@ describe('/api/files/presigned', () => {
         storageProvider: 's3',
       })
 
-      const request = new NextRequest('http://localhost:3000/api/files/presigned?type=chat', {
-        method: 'POST',
-        body: JSON.stringify({
-          fileName: 'test.txt',
-          contentType: 'text/plain',
-          fileSize: 1024,
-        }),
-      })
+      const request = new NextRequest(
+        'http://localhost:3000/api/files/presigned?type=profile-pictures',
+        {
+          method: 'POST',
+          body: JSON.stringify({
+            fileName: 'avatar.png',
+            contentType: 'image/png',
+            fileSize: 1024,
+          }),
+        }
+      )
 
       const response = await POST(request)
       const data = await response.json()
@@ -235,11 +238,11 @@ describe('/api/files/presigned', () => {
       expect(response.status).toBe(200)
       expect(data.directUploadSupported).toBe(false)
       expect(data.presignedUrl).toBe('')
-      expect(data.fileName).toBe('test.txt')
+      expect(data.fileName).toBe('avatar.png')
       expect(data.fileInfo).toBeDefined()
-      expect(data.fileInfo.name).toBe('test.txt')
+      expect(data.fileInfo.name).toBe('avatar.png')
       expect(data.fileInfo.size).toBe(1024)
-      expect(data.fileInfo.type).toBe('text/plain')
+      expect(data.fileInfo.type).toBe('image/png')
     })
 
     it('should return error when fileName is missing', async () => {
@@ -339,14 +342,17 @@ describe('/api/files/presigned', () => {
         storageProvider: 's3',
       })
 
-      const request = new NextRequest('http://localhost:3000/api/files/presigned?type=chat', {
-        method: 'POST',
-        body: JSON.stringify({
-          fileName: 'test document.txt',
-          contentType: 'text/plain',
-          fileSize: 1024,
-        }),
-      })
+      const request = new NextRequest(
+        'http://localhost:3000/api/files/presigned?type=profile-pictures',
+        {
+          method: 'POST',
+          body: JSON.stringify({
+            fileName: 'test avatar.png',
+            contentType: 'image/png',
+            fileSize: 1024,
+          }),
+        }
+      )
 
       const response = await POST(request)
       const data = await response.json()
@@ -354,11 +360,11 @@ describe('/api/files/presigned', () => {
       expect(response.status).toBe(200)
       expect(data.presignedUrl).toBe('https://example.com/presigned-url')
       expect(data.fileInfo).toMatchObject({
-        path: expect.stringMatching(/\/api\/files\/serve\/s3\/.+\?context=chat$/),
-        key: expect.stringMatching(/.*test.document\.txt$/),
-        name: 'test document.txt',
+        path: expect.stringMatching(/\/api\/files\/serve\/s3\/.+\?context=profile-pictures$/),
+        key: expect.stringMatching(/.*test.avatar\.png$/),
+        name: 'test avatar.png',
         size: 1024,
-        type: 'text/plain',
+        type: 'image/png',
       })
       expect(data.directUploadSupported).toBe(true)
     })
@@ -389,27 +395,30 @@ describe('/api/files/presigned', () => {
       expect(data.directUploadSupported).toBe(true)
     })
 
-    it('should generate chat S3 presigned URL with chat prefix and direct path', async () => {
+    it('should generate profile-pictures S3 presigned URL with its prefix and direct path', async () => {
       setupFileApiMocks({
         cloudEnabled: true,
         storageProvider: 's3',
       })
 
-      const request = new NextRequest('http://localhost:3000/api/files/presigned?type=chat', {
-        method: 'POST',
-        body: JSON.stringify({
-          fileName: 'chat-logo.png',
-          contentType: 'image/png',
-          fileSize: 4096,
-        }),
-      })
+      const request = new NextRequest(
+        'http://localhost:3000/api/files/presigned?type=profile-pictures',
+        {
+          method: 'POST',
+          body: JSON.stringify({
+            fileName: 'avatar.png',
+            contentType: 'image/png',
+            fileSize: 4096,
+          }),
+        }
+      )
 
       const response = await POST(request)
       const data = await response.json()
 
       expect(response.status).toBe(200)
-      expect(data.fileInfo.key).toMatch(/^chat\/.*chat-logo\.png$/)
-      expect(data.fileInfo.path).toMatch(/\/api\/files\/serve\/s3\/.+\?context=chat$/)
+      expect(data.fileInfo.key).toMatch(/^profile-pictures\/.*avatar\.png$/)
+      expect(data.fileInfo.path).toMatch(/\/api\/files\/serve\/s3\/.+\?context=profile-pictures$/)
       expect(data.presignedUrl).toBeTruthy()
       expect(data.directUploadSupported).toBe(true)
     })
@@ -420,14 +429,17 @@ describe('/api/files/presigned', () => {
         storageProvider: 'blob',
       })
 
-      const request = new NextRequest('http://localhost:3000/api/files/presigned?type=chat', {
-        method: 'POST',
-        body: JSON.stringify({
-          fileName: 'test document.txt',
-          contentType: 'text/plain',
-          fileSize: 1024,
-        }),
-      })
+      const request = new NextRequest(
+        'http://localhost:3000/api/files/presigned?type=profile-pictures',
+        {
+          method: 'POST',
+          body: JSON.stringify({
+            fileName: 'test avatar.png',
+            contentType: 'image/png',
+            fileSize: 1024,
+          }),
+        }
+      )
 
       const response = await POST(request)
       const data = await response.json()
@@ -436,35 +448,38 @@ describe('/api/files/presigned', () => {
       expect(data.presignedUrl).toBeTruthy()
       expect(typeof data.presignedUrl).toBe('string')
       expect(data.fileInfo).toMatchObject({
-        key: expect.stringMatching(/.*test.document\.txt$/),
-        name: 'test document.txt',
+        key: expect.stringMatching(/.*test.avatar\.png$/),
+        name: 'test avatar.png',
         size: 1024,
-        type: 'text/plain',
+        type: 'image/png',
       })
       expect(data.directUploadSupported).toBe(true)
     })
 
-    it('should generate chat Azure Blob presigned URL with chat prefix and direct path', async () => {
+    it('should generate profile-pictures Azure Blob presigned URL with its prefix and direct path', async () => {
       setupFileApiMocks({
         cloudEnabled: true,
         storageProvider: 'blob',
       })
 
-      const request = new NextRequest('http://localhost:3000/api/files/presigned?type=chat', {
-        method: 'POST',
-        body: JSON.stringify({
-          fileName: 'chat-logo.png',
-          contentType: 'image/png',
-          fileSize: 4096,
-        }),
-      })
+      const request = new NextRequest(
+        'http://localhost:3000/api/files/presigned?type=profile-pictures',
+        {
+          method: 'POST',
+          body: JSON.stringify({
+            fileName: 'avatar.png',
+            contentType: 'image/png',
+            fileSize: 4096,
+          }),
+        }
+      )
 
       const response = await POST(request)
       const data = await response.json()
 
       expect(response.status).toBe(200)
-      expect(data.fileInfo.key).toMatch(/^chat\/.*chat-logo\.png$/)
-      expect(data.fileInfo.path).toMatch(/\/api\/files\/serve\/blob\/.+\?context=chat$/)
+      expect(data.fileInfo.key).toMatch(/^profile-pictures\/.*avatar\.png$/)
+      expect(data.fileInfo.path).toMatch(/\/api\/files\/serve\/blob\/.+\?context=profile-pictures$/)
       expect(data.presignedUrl).toBeTruthy()
       expect(data.directUploadSupported).toBe(true)
     })
@@ -479,14 +494,17 @@ describe('/api/files/presigned', () => {
         new Error('Unknown storage provider: unknown')
       )
 
-      const request = new NextRequest('http://localhost:3000/api/files/presigned?type=chat', {
-        method: 'POST',
-        body: JSON.stringify({
-          fileName: 'test.txt',
-          contentType: 'text/plain',
-          fileSize: 1024,
-        }),
-      })
+      const request = new NextRequest(
+        'http://localhost:3000/api/files/presigned?type=profile-pictures',
+        {
+          method: 'POST',
+          body: JSON.stringify({
+            fileName: 'avatar.png',
+            contentType: 'image/png',
+            fileSize: 1024,
+          }),
+        }
+      )
 
       const response = await POST(request)
       const data = await response.json()
@@ -506,14 +524,17 @@ describe('/api/files/presigned', () => {
         new Error('S3 service unavailable')
       )
 
-      const request = new NextRequest('http://localhost:3000/api/files/presigned?type=chat', {
-        method: 'POST',
-        body: JSON.stringify({
-          fileName: 'test.txt',
-          contentType: 'text/plain',
-          fileSize: 1024,
-        }),
-      })
+      const request = new NextRequest(
+        'http://localhost:3000/api/files/presigned?type=profile-pictures',
+        {
+          method: 'POST',
+          body: JSON.stringify({
+            fileName: 'avatar.png',
+            contentType: 'image/png',
+            fileSize: 1024,
+          }),
+        }
+      )
 
       const response = await POST(request)
       const data = await response.json()
@@ -533,14 +554,17 @@ describe('/api/files/presigned', () => {
         new Error('Azure service unavailable')
       )
 
-      const request = new NextRequest('http://localhost:3000/api/files/presigned?type=chat', {
-        method: 'POST',
-        body: JSON.stringify({
-          fileName: 'test.txt',
-          contentType: 'text/plain',
-          fileSize: 1024,
-        }),
-      })
+      const request = new NextRequest(
+        'http://localhost:3000/api/files/presigned?type=profile-pictures',
+        {
+          method: 'POST',
+          body: JSON.stringify({
+            fileName: 'avatar.png',
+            contentType: 'image/png',
+            fileSize: 1024,
+          }),
+        }
+      )
 
       const response = await POST(request)
       const data = await response.json()
@@ -568,6 +592,26 @@ describe('/api/files/presigned', () => {
       expect(data.error).toBe('Invalid JSON in request body') // Updated error message
       expect(data.code).toBe('VALIDATION_ERROR')
     })
+
+    it('rejects the unauthorizable chat context without minting a URL', async () => {
+      setupFileApiMocks({ cloudEnabled: true, storageProvider: 's3' })
+
+      const request = new NextRequest('http://localhost:3000/api/files/presigned?type=chat', {
+        method: 'POST',
+        body: JSON.stringify({
+          fileName: 'poc.html',
+          contentType: 'text/html',
+          fileSize: 41,
+        }),
+      })
+
+      const response = await POST(request)
+      const data = await response.json()
+
+      expect(response.status).toBe(400)
+      expect(data.error).toContain('Invalid type parameter')
+      expect(storageServiceMockFns.mockGeneratePresignedUploadUrl).not.toHaveBeenCalled()
+    })
   })
 
   describe('mothership uploads', () => {
diff --git a/apps/sim/app/api/files/presigned/route.ts b/apps/sim/app/api/files/presigned/route.ts
index 0104f78fcc5..49bec3aab16 100644
--- a/apps/sim/app/api/files/presigned/route.ts
+++ b/apps/sim/app/api/files/presigned/route.ts
@@ -1,12 +1,15 @@
 import { createLogger } from '@sim/logger'
 import { getErrorMessage } from '@sim/utils/errors'
 import { type NextRequest, NextResponse } from 'next/server'
-import { presignedUploadBodyContract, uploadTypeSchema } from '@/lib/api/contracts/storage-transfer'
+import {
+  presignedUploadBodyContract,
+  presignedUploadTypeSchema,
+  presignedUploadTypes,
+} from '@/lib/api/contracts/storage-transfer'
 import { getValidationErrorMessage, parseRequest } from '@/lib/api/server'
 import { getSession } from '@/lib/auth'
 import { withRouteHandler } from '@/lib/core/utils/with-route-handler'
 import { CopilotFiles } from '@/lib/uploads'
-import type { StorageContext } from '@/lib/uploads/config'
 import { getServeStoragePrefix } from '@/lib/uploads/config'
 import { generateExecutionFileKey } from '@/lib/uploads/contexts/execution/utils'
 import { generateKnowledgeBaseFileKey } from '@/lib/uploads/contexts/knowledge-base/knowledge-base-file-manager'
@@ -20,16 +23,6 @@ import { createErrorResponse } from '@/app/api/files/utils'
 
 const logger = createLogger('PresignedUploadAPI')
 
-const VALID_UPLOAD_TYPES = [
-  'knowledge-base',
-  'chat',
-  'copilot',
-  'profile-pictures',
-  'mothership',
-  'workspace-logos',
-  'execution',
-] as const
-
 class PresignedUrlError extends Error {
   constructor(
     message: string,
@@ -76,14 +69,14 @@ export const POST = withRouteHandler(async (request: NextRequest) => {
       throw new ValidationError('type query parameter is required')
     }
 
-    const uploadTypeResult = uploadTypeSchema.safeParse(uploadTypeParam)
+    const uploadTypeResult = presignedUploadTypeSchema.safeParse(uploadTypeParam)
     if (!uploadTypeResult.success) {
       throw new ValidationError(
-        `Invalid type parameter. Must be one of: ${VALID_UPLOAD_TYPES.join(', ')}`
+        `Invalid type parameter. Must be one of: ${presignedUploadTypes.join(', ')}`
       )
     }
 
-    const uploadType = uploadTypeResult.data as StorageContext
+    const uploadType = uploadTypeResult.data
 
     if (uploadType === 'knowledge-base') {
       const fileValidationError = validateFileType(fileName, contentType)
@@ -290,17 +283,10 @@ export const POST = withRouteHandler(async (request: NextRequest) => {
         size: fileSize,
       })
     } else {
-      if (uploadType === 'profile-pictures') {
-        if (!sessionUserId?.trim()) {
-          throw new ValidationError(
-            'Authenticated user session is required for profile picture uploads'
-          )
-        }
-        if (!isImageFileType(contentType)) {
-          throw new ValidationError(
-            'Only image files (JPEG, PNG, GIF, WebP, SVG) are allowed for profile picture uploads'
-          )
-        }
+      if (!isImageFileType(contentType)) {
+        throw new ValidationError(
+          'Only image files (JPEG, PNG, GIF, WebP, SVG) are allowed for profile picture uploads'
+        )
       }
 
       presignedUrlResponse = await generatePresignedUploadUrl({
diff --git a/apps/sim/lib/api/contracts/storage-transfer.ts b/apps/sim/lib/api/contracts/storage-transfer.ts
index 7f49d9e797e..b5ad82d362c 100644
--- a/apps/sim/lib/api/contracts/storage-transfer.ts
+++ b/apps/sim/lib/api/contracts/storage-transfer.ts
@@ -338,8 +338,35 @@ export const validUploadTypes = [
 
 export const uploadTypeSchema = z.enum(validUploadTypes)
 
+/**
+ * Storage contexts a client may mint a single presigned upload URL for. Each one
+ * has a per-context authorization predicate in `/api/files/presigned`; a context
+ * that cannot be authorized must not be listed here. `chat` is deliberately
+ * absent — it has no owning entity to authorize against and no client that mints
+ * one (chat assets go through the server-proxied `/api/files/upload`).
+ */
+export const presignedUploadTypes = [
+  'knowledge-base',
+  'copilot',
+  'profile-pictures',
+  'mothership',
+  'workspace-logos',
+  'execution',
+] as const
+
+export const presignedUploadTypeSchema = z.enum(presignedUploadTypes)
+
+/**
+ * Storage contexts `/api/files/presigned/batch` serves. Batching exists only for
+ * knowledge-base ingest; no other context has a batch client, and the batch
+ * endpoint carries no authorization predicate for one.
+ */
+export const batchPresignedUploadTypes = ['knowledge-base'] as const
+
+export const batchPresignedUploadTypeSchema = z.enum(batchPresignedUploadTypes)
+
 export const presignedUploadQuerySchema = z.object({
-  type: uploadTypeSchema,
+  type: presignedUploadTypeSchema,
 })
 
 export const presignedUrlBodySchema = z