diff --git a/apps/sim/lib/credentials/google-workload-identity.server.test.ts b/apps/sim/lib/credentials/google-workload-identity.server.test.ts
index 0de02046d10..07db28f217f 100644
--- a/apps/sim/lib/credentials/google-workload-identity.server.test.ts
+++ b/apps/sim/lib/credentials/google-workload-identity.server.test.ts
@@ -415,27 +415,41 @@ describe('getting a keyless Google Cloud token for a run', () => {
     expect(google.iam[0]?.body).toEqual({ scope: [BIGQUERY], lifetime: '3600s' })
   })
 
-  it('refuses domain-wide delegation before contacting Google', async () => {
-    fakeGoogle(fetch)
+  it.each([
+    ['google-drive', 'google_keyless_delegation'],
+    ['google-bigquery', 'google_keyless_delegation_unavailable'],
+    ['google-ads', 'google_keyless_service_unsupported'],
+  ])(
+    'refuses impersonation for %s before contacting Google, offering delegation only where it exists',
+    async (service, step) => {
+      fakeGoogle(fetch)
 
-    await expect(
-      resolve({ credentialId: 'cred-dwd', impersonateEmail: 'alice@example.com' })
-    ).rejects.toMatchObject({
-      code: 'unsupported_use',
-      logDetail: { step: 'google_keyless_delegation' },
-      userMessage: expect.any(String),
-    })
-    expect(fetch).not.toHaveBeenCalled()
-  })
+      await expect(
+        resolve({ credentialId: 'cred-dwd', service, impersonateEmail: 'alice@example.com' })
+      ).rejects.toMatchObject({
+        code: 'unsupported_use',
+        logDetail: { step },
+        userMessage: expect.any(String),
+      })
+      expect(fetch).not.toHaveBeenCalled()
+    }
+  )
 
-  it.each(['google-drive', 'gmail', 'google-sheets', 'google-ads', undefined])(
-    'refuses %s, which keyless credentials do not serve, before contacting Google',
-    async (service) => {
+  it.each([
+    ['google-drive', 'google_keyless_service'],
+    ['gmail', 'google_keyless_service'],
+    ['google-sheets', 'google_keyless_service'],
+    ['google-email', 'google_keyless_service'],
+    ['google-ads', 'google_keyless_service_unsupported'],
+    [undefined, 'google_keyless_service_unsupported'],
+  ])(
+    'refuses %s, which keyless credentials do not serve, offering delegation only where it exists',
+    async (service, step) => {
       fakeGoogle(fetch)
 
       await expect(resolve({ credentialId: 'cred-workspace', service })).rejects.toMatchObject({
         code: 'unsupported_use',
-        logDetail: { step: 'google_keyless_service' },
+        logDetail: { step },
         userMessage: expect.any(String),
       })
       expect(fetch).not.toHaveBeenCalled()
diff --git a/apps/sim/lib/credentials/google-workload-identity.server.ts b/apps/sim/lib/credentials/google-workload-identity.server.ts
index 6d4a75d2957..52627cc8fc9 100644
--- a/apps/sim/lib/credentials/google-workload-identity.server.ts
+++ b/apps/sim/lib/credentials/google-workload-identity.server.ts
@@ -930,7 +930,9 @@ export async function resolveGoogleWorkloadIdentityToken(
   input: ResolveGoogleWorkloadIdentityTokenInput
 ): Promise<string> {
   const config = readStoredConfig(input.decrypted)
-  const delegation = googleDelegationServiceFor(input.service) ? config.delegation : undefined
+  // Reconnecting can add delegation only for the Workspace services keyless delegation covers.
+  const delegable = googleDelegationServiceFor(input.service) !== undefined
+  const delegation = delegable ? config.delegation : undefined
 
   if (delegation) {
     if (input.impersonateEmail && input.impersonateEmail.trim().toLowerCase() !== delegation.user) {
@@ -941,20 +943,35 @@ export async function resolveGoogleWorkloadIdentityToken(
       )
     }
   } else {
-    if (input.impersonateEmail) {
+    const cloudService = Boolean(input.service && GOOGLE_KEYLESS_SERVICES.has(input.service))
+    // Clearing the Impersonated Account helps only where keyless works without it.
+    if (input.impersonateEmail && delegable) {
       throw unsupportedUse(
         'google_keyless_delegation',
         'this keyless Google credential has no domain-wide delegation for this service',
         'This keyless Google credential has no domain-wide delegation for this service, so it cannot act as a Workspace user. Clear the Impersonated Account, reconnect the credential to delegate this service, or use a JSON key credential instead'
       )
     }
-    if (!input.service || !GOOGLE_KEYLESS_SERVICES.has(input.service)) {
+    if (input.impersonateEmail && cloudService) {
       throw unsupportedUse(
-        'google_keyless_service',
-        'this keyless Google credential works only with Google Cloud APIs and the Workspace services it was delegated',
-        'This keyless Google credential works only with Google Cloud tools such as BigQuery and, through domain-wide delegation, with Gmail, Google Drive, Google Docs, Google Sheets, and Google Calendar. Reconnect it to delegate this service, or use a JSON key credential instead'
+        'google_keyless_delegation_unavailable',
+        'keyless Google credentials cannot act as a Workspace user for this service',
+        'A keyless Google credential cannot act as a Workspace user for this service. Clear the Impersonated Account, or use a JSON key credential instead'
       )
     }
+    if (!cloudService) {
+      throw delegable
+        ? unsupportedUse(
+            'google_keyless_service',
+            'this keyless Google credential works only with Google Cloud APIs and the Workspace services it was delegated',
+            'This keyless Google credential works only with Google Cloud tools such as BigQuery and, through domain-wide delegation, with Gmail, Google Drive, Google Docs, Google Sheets, and Google Calendar. Reconnect it to delegate this service, or use a JSON key credential instead'
+          )
+        : unsupportedUse(
+            'google_keyless_service_unsupported',
+            'keyless Google credentials cannot serve this service',
+            'Keyless Google credentials work only with Google Cloud tools such as BigQuery and, through domain-wide delegation, with Gmail, Google Drive, Google Docs, Google Sheets, and Google Calendar. Use a JSON key credential for this service'
+          )
+    }
   }
   if (input.scopes.length === 0) {
     throw new TokenServiceAccountValidationError('invalid_credentials', 400, {