diff --git a/src/media-understanding/defaults.constants.ts b/src/media-understanding/defaults.constants.ts
new file mode 100644
index 00000000000..2dc0c119d98
--- /dev/null
+++ b/src/media-understanding/defaults.constants.ts
@@ -0,0 +1,32 @@
+import type { MediaUnderstandingCapability } from "./types.js";
+
+const MB = 1024 * 1024;
+
+export const DEFAULT_MAX_CHARS = 500;
+export const DEFAULT_MAX_CHARS_BY_CAPABILITY: Record<
+  MediaUnderstandingCapability,
+  number | undefined
+> = {
+  image: DEFAULT_MAX_CHARS,
+  audio: undefined,
+  video: DEFAULT_MAX_CHARS,
+};
+export const DEFAULT_MAX_BYTES: Record<MediaUnderstandingCapability, number> = {
+  image: 10 * MB,
+  audio: 20 * MB,
+  video: 50 * MB,
+};
+export const DEFAULT_TIMEOUT_SECONDS: Record<MediaUnderstandingCapability, number> = {
+  image: 60,
+  audio: 60,
+  video: 120,
+};
+export const DEFAULT_PROMPT: Record<MediaUnderstandingCapability, string> = {
+  image: "Describe the image.",
+  audio: "Transcribe the audio.",
+  video: "Describe the video.",
+};
+export const DEFAULT_VIDEO_MAX_BASE64_BYTES = 70 * MB;
+export const CLI_OUTPUT_MAX_BUFFER = 5 * MB;
+export const DEFAULT_MEDIA_CONCURRENCY = 2;
+export const MIN_AUDIO_FILE_BYTES = 1024;
diff --git a/src/media-understanding/defaults.ts b/src/media-understanding/defaults.ts
index 0e11d77469d..f071fd36103 100644
--- a/src/media-understanding/defaults.ts
+++ b/src/media-understanding/defaults.ts
@@ -5,36 +5,17 @@ import { buildMediaUnderstandingManifestMetadataRegistry } from "./manifest-meta
 import { normalizeMediaProviderId } from "./provider-registry.js";
 import { providerSupportsCapability } from "./provider-supports.js";
 import type { MediaUnderstandingCapability, MediaUnderstandingProvider } from "./types.js";
-
-const MB = 1024 * 1024;
-
-export const DEFAULT_MAX_CHARS = 500;
-export const DEFAULT_MAX_CHARS_BY_CAPABILITY: Record<
-  MediaUnderstandingCapability,
-  number | undefined
-> = {
-  image: DEFAULT_MAX_CHARS,
-  audio: undefined,
-  video: DEFAULT_MAX_CHARS,
-};
-export const DEFAULT_MAX_BYTES: Record<MediaUnderstandingCapability, number> = {
-  image: 10 * MB,
-  audio: 20 * MB,
-  video: 50 * MB,
-};
-export const DEFAULT_TIMEOUT_SECONDS: Record<MediaUnderstandingCapability, number> = {
-  image: 60,
-  audio: 60,
-  video: 120,
-};
-export const DEFAULT_PROMPT: Record<MediaUnderstandingCapability, string> = {
-  image: "Describe the image.",
-  audio: "Transcribe the audio.",
-  video: "Describe the video.",
-};
-export const DEFAULT_VIDEO_MAX_BASE64_BYTES = 70 * MB;
-export const CLI_OUTPUT_MAX_BUFFER = 5 * MB;
-export const DEFAULT_MEDIA_CONCURRENCY = 2;
+export {
+  CLI_OUTPUT_MAX_BUFFER,
+  DEFAULT_MAX_BYTES,
+  DEFAULT_MAX_CHARS,
+  DEFAULT_MAX_CHARS_BY_CAPABILITY,
+  DEFAULT_MEDIA_CONCURRENCY,
+  DEFAULT_PROMPT,
+  DEFAULT_TIMEOUT_SECONDS,
+  DEFAULT_VIDEO_MAX_BASE64_BYTES,
+  MIN_AUDIO_FILE_BYTES,
+} from "./defaults.constants.js";
 
 let defaultRegistryCache: Map<string, MediaUnderstandingProvider> | null = null;
 const configRegistryCache = new Map<string, Map<string, MediaUnderstandingProvider>>();
@@ -192,10 +173,3 @@ export function providerSupportsNativePdfDocument(params: {
   const provider = registry.get(normalizeMediaProviderId(params.providerId));
   return provider?.nativeDocumentInputs?.includes("pdf") ?? false;
 }
-
-/**
- * Minimum audio file size in bytes below which transcription is skipped.
- * Files smaller than this threshold are almost certainly empty or corrupt
- * and would cause unhelpful API errors from Whisper/transcription providers.
- */
-export const MIN_AUDIO_FILE_BYTES = 1024;
diff --git a/src/media-understanding/resolve.ts b/src/media-understanding/resolve.ts
index 0b28a776e20..334ef4357aa 100644
--- a/src/media-understanding/resolve.ts
+++ b/src/media-understanding/resolve.ts
@@ -11,7 +11,7 @@ import {
   DEFAULT_MAX_CHARS_BY_CAPABILITY,
   DEFAULT_MEDIA_CONCURRENCY,
   DEFAULT_PROMPT,
-} from "./defaults.js";
+} from "./defaults.constants.js";
 import { resolveEffectiveMediaEntryCapabilities } from "./entry-capabilities.js";
 import { normalizeMediaProviderId } from "./provider-id.js";
 import { normalizeMediaUnderstandingChatType, resolveMediaUnderstandingScope } from "./scope.js";
diff --git a/src/media-understanding/runner.entries.ts b/src/media-understanding/runner.entries.ts
index 49ec18a29be..1a4f49dec6b 100644
--- a/src/media-understanding/runner.entries.ts
+++ b/src/media-understanding/runner.entries.ts
@@ -27,8 +27,7 @@ import {
   CLI_OUTPUT_MAX_BUFFER,
   DEFAULT_TIMEOUT_SECONDS,
   MIN_AUDIO_FILE_BYTES,
-  resolveDefaultMediaModel,
-} from "./defaults.js";
+} from "./defaults.constants.js";
 import { MediaUnderstandingSkipError } from "./errors.js";
 import { fileExists } from "./fs.js";
 import { describeImageWithModel } from "./image-runtime.js";
@@ -632,7 +631,7 @@ export async function runProviderEntry(params: {
     });
     const model =
       entry.model?.trim() ||
-      resolveDefaultMediaModel({
+      (await import("./defaults.js")).resolveDefaultMediaModel({
         cfg,
         providerId,
         capability: "audio",
diff --git a/src/media-understanding/runner.test-utils.ts b/src/media-understanding/runner.test-utils.ts
index 44818df0ce8..46722b535e6 100644
--- a/src/media-understanding/runner.test-utils.ts
+++ b/src/media-understanding/runner.test-utils.ts
@@ -2,7 +2,7 @@ import fs from "node:fs/promises";
 import os from "node:os";
 import path from "node:path";
 import { withEnvAsync } from "../test-utils/env.js";
-import { MIN_AUDIO_FILE_BYTES } from "./defaults.js";
+import { MIN_AUDIO_FILE_BYTES } from "./defaults.constants.js";
 import { createMediaAttachmentCache, normalizeMediaAttachments } from "./runner.attachments.js";
 
 type MediaFixtureParams = {
diff --git a/src/media-understanding/runner.video.test.ts b/src/media-understanding/runner.video.test.ts
index 2b5a1ba166d..58647ba9f02 100644
--- a/src/media-understanding/runner.video.test.ts
+++ b/src/media-understanding/runner.video.test.ts
@@ -5,6 +5,18 @@ import { withEnvAsync } from "../test-utils/env.js";
 import { runCapability } from "./runner.js";
 import { withVideoFixture } from "./runner.test-utils.js";
 
+vi.mock("../media/channel-inbound-roots.js", () => ({
+  resolveChannelInboundAttachmentRoots: () => undefined,
+}));
+
+vi.mock("../agents/api-key-rotation.js", () => ({
+  collectProviderApiKeysForExecution: ({ primaryApiKey }: { primaryApiKey?: string }) => [
+    primaryApiKey ?? "test-key",
+  ],
+  executeWithApiKeyRotation: async <T>({ execute }: { execute: (apiKey: string) => Promise<T> }) =>
+    execute("test-key"),
+}));
+
 vi.mock("../plugins/capability-provider-runtime.js", async () => {
   const { createEmptyCapabilityProviderMockModule } = await import("./runner.test-mocks.js");
   return createEmptyCapabilityProviderMockModule();
diff --git a/src/media-understanding/video.ts b/src/media-understanding/video.ts
index 00773f40ca7..827b635ba03 100644
--- a/src/media-understanding/video.ts
+++ b/src/media-understanding/video.ts
@@ -1,4 +1,4 @@
-import { DEFAULT_VIDEO_MAX_BASE64_BYTES } from "./defaults.js";
+import { DEFAULT_VIDEO_MAX_BASE64_BYTES } from "./defaults.constants.js";
 
 export function estimateBase64Size(bytes: number): number {
   return Math.ceil(bytes / 3) * 4;
diff --git a/src/plugins/web-search-providers.runtime.test.ts b/src/plugins/web-search-providers.runtime.test.ts
index 3001bce7250..6f1d9ea6651 100644
--- a/src/plugins/web-search-providers.runtime.test.ts
+++ b/src/plugins/web-search-providers.runtime.test.ts
@@ -3,9 +3,11 @@ import { afterEach, beforeAll, beforeEach, describe, expect, it, vi } from "vite
 type RegistryModule = typeof import("./registry.js");
 type RuntimeModule = typeof import("./runtime.js");
 type WebSearchProvidersRuntimeModule = typeof import("./web-search-providers.runtime.js");
-type ManifestRegistryModule = typeof import("./manifest-registry.js");
 type PluginAutoEnableModule = typeof import("../config/plugin-auto-enable.js");
 type WebSearchProvidersSharedModule = typeof import("./web-search-providers.shared.js");
+type PluginManifestRegistry = import("./manifest-registry.js").PluginManifestRegistry;
+type LoadPluginManifestRegistryForPluginRegistry =
+  typeof import("./plugin-registry.js").loadPluginManifestRegistryForPluginRegistry;
 
 const BUNDLED_WEB_SEARCH_PROVIDERS = [
   { pluginId: "brave", id: "brave", order: 10 },
@@ -20,13 +22,14 @@ const BUNDLED_WEB_SEARCH_PROVIDERS = [
 ] as const;
 
 let createEmptyPluginRegistry: RegistryModule["createEmptyPluginRegistry"];
-let loadPluginManifestRegistryMock: ReturnType<typeof vi.fn>;
+let loadPluginManifestRegistryMock: ReturnType<
+  typeof vi.fn<LoadPluginManifestRegistryForPluginRegistry>
+>;
 let setActivePluginRegistry: RuntimeModule["setActivePluginRegistry"];
 let resolvePluginWebSearchProviders: WebSearchProvidersRuntimeModule["resolvePluginWebSearchProviders"];
 let resolveRuntimeWebSearchProviders: WebSearchProvidersRuntimeModule["resolveRuntimeWebSearchProviders"];
 let loadOpenClawPluginsMock: ReturnType<typeof vi.fn>;
 let loaderModule: typeof import("./loader.js");
-let manifestRegistryModule: ManifestRegistryModule;
 let pluginAutoEnableModule: PluginAutoEnableModule;
 let applyPluginAutoEnableSpy: ReturnType<typeof vi.fn>;
 let webSearchProvidersSharedModule: WebSearchProvidersSharedModule;
@@ -135,7 +138,7 @@ function expectBundledRuntimeProviderKeys(
   );
 }
 
-function createManifestRegistryFixture() {
+function createManifestRegistryFixture(): PluginManifestRegistry {
   return {
     plugins: [
       {
@@ -316,8 +319,19 @@ function expectRuntimeProviderResolution(
 
 describe("resolvePluginWebSearchProviders", () => {
   beforeAll(async () => {
+    loadPluginManifestRegistryMock = vi.fn<LoadPluginManifestRegistryForPluginRegistry>();
+    vi.doMock("./plugin-registry.js", async () => {
+      const actual =
+        await vi.importActual<typeof import("./plugin-registry.js")>("./plugin-registry.js");
+      return {
+        ...actual,
+        loadPluginManifestRegistryForPluginRegistry: (
+          ...args: Parameters<LoadPluginManifestRegistryForPluginRegistry>
+        ) => loadPluginManifestRegistryMock(...args),
+      };
+    });
+
     ({ createEmptyPluginRegistry } = await import("./registry-empty.js"));
-    manifestRegistryModule = await import("./manifest-registry.js");
     loaderModule = await import("./loader.js");
     pluginAutoEnableModule = await import("../config/plugin-auto-enable.js");
     webSearchProvidersSharedModule = await import("./web-search-providers.shared.js");
@@ -338,15 +352,8 @@ describe("resolvePluginWebSearchProviders", () => {
             autoEnabledReasons: {},
           }) as ReturnType<PluginAutoEnableModule["applyPluginAutoEnable"]>,
       );
-    loadPluginManifestRegistryMock = vi
-      .spyOn(manifestRegistryModule, "loadPluginManifestRegistry")
-      .mockReturnValue(
-        createManifestRegistryFixture() as ManifestRegistryModule["loadPluginManifestRegistry"] extends (
-          ...args: unknown[]
-        ) => infer R
-          ? R
-          : never,
-      );
+    loadPluginManifestRegistryMock.mockReset();
+    loadPluginManifestRegistryMock.mockReturnValue(createManifestRegistryFixture());
     loadOpenClawPluginsMock = vi
       .spyOn(loaderModule, "loadOpenClawPlugins")
       .mockImplementation((params) => {