diff --git a/packages/zoe/src/typeGuards.js b/packages/zoe/src/typeGuards.js
index 14af2f0a1ed..cbc330fa374 100644
--- a/packages/zoe/src/typeGuards.js
+++ b/packages/zoe/src/typeGuards.js
@@ -276,10 +276,12 @@ export const ZoeStorageManagerIKit = harden({
     getBundleIDFromInstallation: M.call(InstallationShape).returns(
       M.eref(M.string()),
     ),
-    installBundle: M.call(M.or(InstanceHandleShape, BundleShape)).returns(
-      M.promise(),
-    ),
-    installBundleID: M.call(M.string()).returns(M.promise()),
+    installBundle: M.call(M.or(InstanceHandleShape, BundleShape))
+      .optional(M.string())
+      .returns(M.promise()),
+    installBundleID: M.call(M.string())
+      .optional(M.string())
+      .returns(M.promise()),
 
     getPublicFacet: M.call(InstanceHandleShape).returns(
       M.eref(M.remotable('PublicFacet')),
@@ -310,6 +312,7 @@ export const ZoeStorageManagerIKit = harden({
       IssuerPKeywordRecordShape,
       M.or(InstanceHandleShape, BundleShape),
       M.or(BundleCapShape, BundleShape),
+      M.string(),
     ).returns(M.promise()),
     unwrapInstallation: M.callWhen(M.eref(InstallationShape)).returns(
       UnwrappedInstallationShape,
@@ -321,10 +324,10 @@ export const ZoeStorageManagerIKit = harden({
 });
 
 export const ZoeServiceI = M.interface('ZoeService', {
-  install: M.call(M.any()).returns(M.promise()),
-  installBundleID: M.call(M.string()).returns(M.promise()),
+  install: M.call(M.any()).optional(M.string()).returns(M.promise()),
+  installBundleID: M.call(M.string()).optional(M.string()).returns(M.promise()),
   startInstance: M.call(M.eref(InstallationShape))
-    .optional(IssuerPKeywordRecordShape, M.any(), M.any())
+    .optional(IssuerPKeywordRecordShape, M.record(), M.record(), M.string())
     .returns(M.promise()),
   offer: M.call(M.eref(InvitationShape))
     .optional(ProposalShape, PaymentPKeywordRecordShape, M.any())
diff --git a/packages/zoe/src/zoeService/installationStorage.js b/packages/zoe/src/zoeService/installationStorage.js
index 9b12197d706..b06c5ed26cf 100644
--- a/packages/zoe/src/zoeService/installationStorage.js
+++ b/packages/zoe/src/zoeService/installationStorage.js
@@ -84,8 +84,12 @@ export const makeInstallationStorage = (getBundleCapForID, zoeBaggage) => {
         InstanceHandleShape,
         M.recordOf(M.string(), M.string({ stringLengthLimit: Infinity })),
       ),
-    ).returns(M.promise()),
-    installBundleID: M.call(M.string()).returns(M.promise()),
+    )
+      .optional(M.string())
+      .returns(M.promise()),
+    installBundleID: M.call(M.string())
+      .optional(M.string())
+      .returns(M.promise()),
     unwrapInstallation: M.callWhen(M.await(InstallationShape)).returns(
       UnwrappedInstallationShape,
     ),
diff --git a/packages/zoe/test/unitTests/test-zoe.js b/packages/zoe/test/unitTests/test-zoe.js
index 6d98ddec86c..65b31efae82 100644
--- a/packages/zoe/test/unitTests/test-zoe.js
+++ b/packages/zoe/test/unitTests/test-zoe.js
@@ -55,6 +55,15 @@ test(`E(zoe).installBundleID bad id`, async t => {
   });
 });
 
+test(`E(zoe).installBundleID bad label`, async t => {
+  const { zoe } = setup();
+  // @ts-expect-error deliberate invalid arguments for testing
+  await t.throwsAsync(() => E(zoe).installBundleID('a', harden([])), {
+    message:
+      'In "installBundleID" method of (ZoeService): arg 1?: copyArray [] - Must be a string',
+  });
+});
+
 test(`E(zoe).installBundleID(bundleID)`, async t => {
   const { zoe, vatAdminState } = setup();
   const contractPath = `${dirname}/../../src/contracts/atomicSwap`;