diff --git a/apps/sim/app/api/credentials/[id]/route.test.ts b/apps/sim/app/api/credentials/[id]/route.test.ts
new file mode 100644
index 00000000000..f3c7ea98e94
--- /dev/null
+++ b/apps/sim/app/api/credentials/[id]/route.test.ts
@@ -0,0 +1,58 @@
+/**
+ * @vitest-environment node
+ */
+import { authMockFns, createMockRequest } from '@sim/testing'
+import { beforeEach, describe, expect, it, vi } from 'vitest'
+import { CredentialAccessRequiredError } from '@/lib/credentials/application/authorized-credential-use-case'
+
+const mocks = vi.hoisted(() => ({
+  read: vi.fn(),
+  update: vi.fn(),
+  remove: vi.fn(),
+}))
+
+vi.mock('@/lib/credentials/application/credential-crud', () => ({
+  CredentialProviderOperationError: class CredentialProviderOperationError extends Error {},
+  getWorkspaceCredentialUseCase: {
+    operation: { id: 'credentials.read' },
+    execute: mocks.read,
+  },
+  updateWorkspaceCredentialUseCase: {
+    operation: { id: 'credentials.update' },
+    execute: mocks.update,
+  },
+}))
+
+vi.mock('@/lib/credentials/application/service-account', () => ({
+  deleteCredentialUseCase: {
+    operation: { id: 'credentials.delete' },
+    execute: mocks.remove,
+  },
+}))
+
+import { GET } from '@/app/api/credentials/[id]/route'
+
+const CREDENTIAL_ID = 'credential-1'
+const routeContext = { params: Promise.resolve({ id: CREDENTIAL_ID }) }
+
+describe('GET /api/credentials/[id]', () => {
+  beforeEach(() => {
+    vi.clearAllMocks()
+    authMockFns.mockGetSession.mockResolvedValue({
+      user: { id: 'writer-1' },
+      session: { id: 'session-1' },
+    })
+  })
+
+  it('preserves the generic denial for a workspace writer without credential access', async () => {
+    mocks.read.mockRejectedValue(new CredentialAccessRequiredError())
+
+    const response = await GET(
+      createMockRequest('GET', undefined, {}, `http://localhost/api/credentials/${CREDENTIAL_ID}`),
+      routeContext
+    )
+
+    expect(response.status).toBe(403)
+    expect(await response.json()).toEqual({ error: 'Forbidden' })
+  })
+})
diff --git a/apps/sim/app/api/credentials/[id]/route.ts b/apps/sim/app/api/credentials/[id]/route.ts
index d99ad8382c4..0010a8af252 100644
--- a/apps/sim/app/api/credentials/[id]/route.ts
+++ b/apps/sim/app/api/credentials/[id]/route.ts
@@ -10,6 +10,7 @@ import {
 } from '@/lib/api/server/routes'
 import {
   credentialValidationParseOptions,
+  internalCredentialDetailErrorPolicy,
   internalCredentialErrorPolicy,
 } from '@/lib/credentials/api/route-policies'
 import {
@@ -27,7 +28,7 @@ export const GET = defineInternalJsonRoute({
   auth: internalSessionAuth,
   operation: credentialOperations.read,
   rateLimit,
-  errorPolicy: internalCredentialErrorPolicy,
+  errorPolicy: internalCredentialDetailErrorPolicy,
   parseOptions: credentialValidationParseOptions,
   mapInput: ({ params }) => ({ credentialId: params.id }),
   useCase: getWorkspaceCredentialUseCase,
diff --git a/apps/sim/lib/credentials/api/route-policies.ts b/apps/sim/lib/credentials/api/route-policies.ts
index 8e97f55c2ce..717766dec51 100644
--- a/apps/sim/lib/credentials/api/route-policies.ts
+++ b/apps/sim/lib/credentials/api/route-policies.ts
@@ -7,6 +7,7 @@ import { getValidationErrorMessage, validationErrorResponse } from '@/lib/api/se
 import { NoWorkspaceAccessError } from '@/lib/core/application'
 import { ForbiddenOperationError } from '@/lib/core/application/forbidden'
 import { OrchestrationError } from '@/lib/core/orchestration/types'
+import { CredentialAccessRequiredError } from '@/lib/credentials/application/authorized-credential-use-case'
 import { CredentialProviderOperationError } from '@/lib/credentials/application/credential-crud'
 
 export const credentialValidationParseOptions = {
@@ -25,6 +26,14 @@ export const internalCredentialErrorPolicy = extendInternalErrorPolicy(
   }
 )
 
+export const internalCredentialDetailErrorPolicy = extendInternalErrorPolicy(
+  internalCredentialErrorPolicy,
+  (error) =>
+    error instanceof CredentialAccessRequiredError
+      ? internalErrorResponse(403, { error: 'Forbidden' })
+      : null
+)
+
 export const internalCredentialMemberListErrorPolicy = extendInternalErrorPolicy(
   internalCredentialErrorPolicy,
   (error) => {
diff --git a/apps/sim/lib/credentials/application/authorized-credential-use-case.test.ts b/apps/sim/lib/credentials/application/authorized-credential-use-case.test.ts
index dbfe9f99157..b0a1939edfd 100644
--- a/apps/sim/lib/credentials/application/authorized-credential-use-case.test.ts
+++ b/apps/sim/lib/credentials/application/authorized-credential-use-case.test.ts
@@ -3,7 +3,10 @@
  */
 import { beforeEach, describe, expect, it, vi } from 'vitest'
 import { defineWorkspaceOperation } from '@/lib/core/application'
-import { defineAuthorizedCredentialUseCase } from '@/lib/credentials/application/authorized-credential-use-case'
+import {
+  CredentialAccessRequiredError,
+  defineAuthorizedCredentialUseCase,
+} from '@/lib/credentials/application/authorized-credential-use-case'
 import { defineCredentialOperation } from '@/lib/credentials/application/operations'
 
 const mocks = vi.hoisted(() => ({
@@ -85,6 +88,20 @@ describe('defineAuthorizedCredentialUseCase', () => {
     expect(mocks.execute).toHaveBeenCalledOnce()
   })
 
+  it('denies member-level reads without credential membership', async () => {
+    mocks.getActor.mockResolvedValue({
+      credential,
+      member: null,
+      hasWorkspaceAccess: true,
+      isAdmin: false,
+    })
+
+    await expect(
+      createUseCase(memberOperation).execute({ principal, input: undefined })
+    ).rejects.toBeInstanceOf(CredentialAccessRequiredError)
+    expect(mocks.execute).not.toHaveBeenCalled()
+  })
+
   it('requires credential admin independently of workspace read access', async () => {
     await expect(
       createUseCase(adminOperation).execute({ principal, input: undefined })
diff --git a/apps/sim/lib/credentials/application/authorized-credential-use-case.ts b/apps/sim/lib/credentials/application/authorized-credential-use-case.ts
index 635fc9eb621..57e6d109993 100644
--- a/apps/sim/lib/credentials/application/authorized-credential-use-case.ts
+++ b/apps/sim/lib/credentials/application/authorized-credential-use-case.ts
@@ -17,6 +17,13 @@ export interface CredentialAuthorizationContext extends WorkspaceAuthorizationCo
   credentialAccess?: CredentialActorContext
 }
 
+export class CredentialAccessRequiredError extends OrchestrationError {
+  constructor() {
+    super('forbidden', 'Credential access required')
+    this.name = 'CredentialAccessRequiredError'
+  }
+}
+
 export function requireCredentialAccess(
   context: CredentialAuthorizationContext
 ): CredentialActorContext {
@@ -61,7 +68,7 @@ export function defineAuthorizedCredentialUseCase<
       switch (definition.operation.minimumCredentialRole) {
         case 'member':
           if (!actor.member && !actor.isAdmin) {
-            throw new OrchestrationError('forbidden', 'Credential access required')
+            throw new CredentialAccessRequiredError()
           }
           return
         case 'admin':