diff --git a/components/developer/scenario-selector.tsx b/components/developer/scenario-selector.tsx
index d5438fc..fe05936 100644
--- a/components/developer/scenario-selector.tsx
+++ b/components/developer/scenario-selector.tsx
@@ -10,7 +10,7 @@
 import { useState, useId } from "react";
 import { Button } from "@/components/ui/button";
 import { Select } from "@/components/ui/select";
-import { applyMockScenario, resetMockData } from "@/lib/api/mock";
+import { applyMockScenario, resetMockData } from "@/lib/api";
 import { config } from "@/lib/config";
 
 type MockScenario =
diff --git a/lib/api/index.ts b/lib/api/index.ts
index b1288fe..7cdfa34 100644
--- a/lib/api/index.ts
+++ b/lib/api/index.ts
@@ -1,15 +1,13 @@
 import { config } from '../config'
 import { LiveAccessApi } from './live'
 import {
-  MockAccessApi,
+  createMockAccessApi,
   resetMockData,
   applyMockScenario,
   replayMockEvent,
   setMockRoleMutationFailure,
   setMockMetaVersion,
-  setMockResourceFetchFailure,
-  setMockResourceFetchDelay,
-} from './mock'
+} from './mock-boundary'
 import { AccessApi } from './types'
 import type { VersionCompatibility } from './version'
 
@@ -25,7 +23,7 @@ export type { VersionCompatibility }
  * @param communityId Scoped community ID or slug
  */
 export function getApi(address?: string, token?: string, communityId?: string): AccessApi {
-  if (config.apiMode === 'mock') return new MockAccessApi(address, communityId)
+  if (config.apiMode === 'mock') return createMockAccessApi(address, communityId)
   const api = new LiveAccessApi(address, token, communityId)
   // Kick off the startup version compatibility check. It resolves in the
   // background; callers can await api.checkVersion() for the result.
@@ -41,9 +39,7 @@ export {
   replayMockEvent,
   setMockRoleMutationFailure,
   setMockMetaVersion,
-  setMockResourceFetchFailure,
-  setMockResourceFetchDelay,
-} from './mock'
+} from './mock-boundary'
 export {
   ApiError,
   AuthError,
diff --git a/lib/api/mock-boundary.ts b/lib/api/mock-boundary.ts
new file mode 100644
index 0000000..0eea141
--- /dev/null
+++ b/lib/api/mock-boundary.ts
@@ -0,0 +1,22 @@
+import type { AccessApi } from './types'
+import { MockAccessApi } from './mock'
+
+/**
+ * Stable application-facing boundary for mock-only controls.
+ *
+ * Keep this list deliberately small. Application code should import these
+ * symbols from `@/lib/api`; tests of the mock implementation may continue to
+ * import `./mock` directly.
+ */
+export {
+  applyMockScenario,
+  replayMockEvent,
+  resetMockData,
+  setMockMetaVersion,
+  setMockRoleMutationFailure,
+} from './mock'
+
+/** Creates the mock client without exposing its concrete implementation. */
+export function createMockAccessApi(address?: string, communityId?: string): AccessApi {
+  return new MockAccessApi(address, communityId)
+}
diff --git a/test/api-mock-boundary.test.ts b/test/api-mock-boundary.test.ts
new file mode 100644
index 0000000..677d03f
--- /dev/null
+++ b/test/api-mock-boundary.test.ts
@@ -0,0 +1,19 @@
+import assert from 'node:assert/strict'
+import { test } from 'node:test'
+
+import {
+  applyMockScenario,
+  replayMockEvent,
+  resetMockData,
+  setMockMetaVersion,
+  setMockRoleMutationFailure,
+} from '../lib/api'
+
+test('the API boundary exposes the application mock controls', () => {
+  assert.equal(typeof applyMockScenario, 'function')
+  assert.equal(typeof replayMockEvent, 'function')
+  assert.equal(typeof resetMockData, 'function')
+  assert.equal(typeof setMockMetaVersion, 'function')
+  assert.equal(typeof setMockRoleMutationFailure, 'function')
+})
+