diff --git a/packages/plugin-sdk/tsconfig.json b/packages/plugin-sdk/tsconfig.json
index 38d5997dbfc..396b68022a5 100644
--- a/packages/plugin-sdk/tsconfig.json
+++ b/packages/plugin-sdk/tsconfig.json
@@ -27,6 +27,7 @@
     "../../src/plugin-sdk/provider-onboard.ts",
     "../../src/plugin-sdk/provider-stream-shared.ts",
     "../../src/plugin-sdk/provider-tools.ts",
+    "../../src/plugin-sdk/provider-web-search-contract.ts",
     "../../src/plugin-sdk/provider-web-search.ts",
     "../../src/plugin-sdk/runtime-doctor.ts",
     "../../src/plugin-sdk/runtime-env.ts",
diff --git a/src/config/schema.base.generated.ts b/src/config/schema.base.generated.ts
index 90c06e2c8a2..a36c6698dbd 100644
--- a/src/config/schema.base.generated.ts
+++ b/src/config/schema.base.generated.ts
@@ -3175,6 +3175,9 @@ export const GENERATED_BASE_CONFIG_SCHEMA: BaseConfigSchemaResponse = {
                 description:
                   "Optional repository root shown in the system prompt runtime line (overrides auto-detect).",
               },
+              systemPromptOverride: {
+                type: "string",
+              },
               skipBootstrap: {
                 type: "boolean",
               },
@@ -5376,6 +5379,9 @@ export const GENERATED_BASE_CONFIG_SCHEMA: BaseConfigSchemaResponse = {
                 agentDir: {
                   type: "string",
                 },
+                systemPromptOverride: {
+                  type: "string",
+                },
                 model: {
                   anyOf: [
                     {
diff --git a/src/media-generation/provider-capabilities.contract.test.ts b/src/media-generation/provider-capabilities.contract.test.ts
index dda97f85694..cbf2c6e9753 100644
--- a/src/media-generation/provider-capabilities.contract.test.ts
+++ b/src/media-generation/provider-capabilities.contract.test.ts
@@ -1,98 +1,31 @@
 import { describe, expect, it } from "vitest";
+import {
+  loadBundledMusicGenerationProviders,
+  loadBundledVideoGenerationProviders,
+} from "../../test/helpers/media-generation/bundled-provider-builders.js";
 import { listSupportedMusicGenerationModes } from "../music-generation/capabilities.js";
-import type { MusicGenerationProvider } from "../music-generation/types.js";
 import { BUNDLED_PLUGIN_CONTRACT_SNAPSHOTS } from "../plugins/contracts/inventory/bundled-capability-metadata.js";
 import { listSupportedVideoGenerationModes } from "../video-generation/capabilities.js";
-import type { VideoGenerationProvider } from "../video-generation/types.js";
-
-type VideoProviderEntry = {
-  pluginId: string;
-  provider: VideoGenerationProvider;
-};
-
-type MusicProviderEntry = {
-  pluginId: string;
-  provider: MusicGenerationProvider;
-};
 
 function expectedBundledVideoProviderPluginIds(): string[] {
-  return BUNDLED_PLUGIN_CONTRACT_SNAPSHOTS.filter((entry) => entry.videoGenerationProviderIds.length > 0)
+  return BUNDLED_PLUGIN_CONTRACT_SNAPSHOTS.filter(
+    (entry) => entry.videoGenerationProviderIds.length > 0,
+  )
     .map((entry) => entry.pluginId)
     .toSorted((left, right) => left.localeCompare(right));
 }
 
 function expectedBundledMusicProviderPluginIds(): string[] {
-  return BUNDLED_PLUGIN_CONTRACT_SNAPSHOTS.filter((entry) => entry.musicGenerationProviderIds.length > 0)
+  return BUNDLED_PLUGIN_CONTRACT_SNAPSHOTS.filter(
+    (entry) => entry.musicGenerationProviderIds.length > 0,
+  )
     .map((entry) => entry.pluginId)
     .toSorted((left, right) => left.localeCompare(right));
 }
 
-async function loadBundledVideoGenerationProviders(): Promise<VideoProviderEntry[]> {
-  const [
-    { buildAlibabaVideoGenerationProvider },
-    { buildBytePlusVideoGenerationProvider },
-    { buildComfyVideoGenerationProvider },
-    { buildFalVideoGenerationProvider },
-    { buildGoogleVideoGenerationProvider },
-    { buildMinimaxVideoGenerationProvider },
-    { buildOpenAIVideoGenerationProvider },
-    { buildQwenVideoGenerationProvider },
-    { buildRunwayVideoGenerationProvider },
-    { buildTogetherVideoGenerationProvider },
-    { buildVydraVideoGenerationProvider },
-    { buildXaiVideoGenerationProvider },
-  ] = await Promise.all([
-    import("../../extensions/alibaba/video-generation-provider.js"),
-    import("../../extensions/byteplus/video-generation-provider.js"),
-    import("../../extensions/comfy/video-generation-provider.js"),
-    import("../../extensions/fal/video-generation-provider.js"),
-    import("../../extensions/google/video-generation-provider.js"),
-    import("../../extensions/minimax/video-generation-provider.js"),
-    import("../../extensions/openai/video-generation-provider.js"),
-    import("../../extensions/qwen/video-generation-provider.js"),
-    import("../../extensions/runway/video-generation-provider.js"),
-    import("../../extensions/together/video-generation-provider.js"),
-    import("../../extensions/vydra/video-generation-provider.js"),
-    import("../../extensions/xai/video-generation-provider.js"),
-  ]);
-
-  return [
-    { pluginId: "alibaba", provider: buildAlibabaVideoGenerationProvider() },
-    { pluginId: "byteplus", provider: buildBytePlusVideoGenerationProvider() },
-    { pluginId: "comfy", provider: buildComfyVideoGenerationProvider() },
-    { pluginId: "fal", provider: buildFalVideoGenerationProvider() },
-    { pluginId: "google", provider: buildGoogleVideoGenerationProvider() },
-    { pluginId: "minimax", provider: buildMinimaxVideoGenerationProvider() },
-    { pluginId: "openai", provider: buildOpenAIVideoGenerationProvider() },
-    { pluginId: "qwen", provider: buildQwenVideoGenerationProvider() },
-    { pluginId: "runway", provider: buildRunwayVideoGenerationProvider() },
-    { pluginId: "together", provider: buildTogetherVideoGenerationProvider() },
-    { pluginId: "vydra", provider: buildVydraVideoGenerationProvider() },
-    { pluginId: "xai", provider: buildXaiVideoGenerationProvider() },
-  ];
-}
-
-async function loadBundledMusicGenerationProviders(): Promise<MusicProviderEntry[]> {
-  const [
-    { buildComfyMusicGenerationProvider },
-    { buildGoogleMusicGenerationProvider },
-    { buildMinimaxMusicGenerationProvider },
-  ] = await Promise.all([
-    import("../../extensions/comfy/music-generation-provider.js"),
-    import("../../extensions/google/music-generation-provider.js"),
-    import("../../extensions/minimax/music-generation-provider.js"),
-  ]);
-
-  return [
-    { pluginId: "comfy", provider: buildComfyMusicGenerationProvider() },
-    { pluginId: "google", provider: buildGoogleMusicGenerationProvider() },
-    { pluginId: "minimax", provider: buildMinimaxMusicGenerationProvider() },
-  ];
-}
-
 describe("bundled media-generation provider capabilities", () => {
-  it("declares explicit mode support for every bundled video-generation provider", async () => {
-    const entries = await loadBundledVideoGenerationProviders();
+  it("declares explicit mode support for every bundled video-generation provider", () => {
+    const entries = loadBundledVideoGenerationProviders();
     expect(entries.map((entry) => entry.pluginId).toSorted()).toEqual(
       expectedBundledVideoProviderPluginIds(),
     );
@@ -133,8 +66,8 @@ describe("bundled media-generation provider capabilities", () => {
     }
   });
 
-  it("declares explicit generate/edit support for every bundled music-generation provider", async () => {
-    const entries = await loadBundledMusicGenerationProviders();
+  it("declares explicit generate/edit support for every bundled music-generation provider", () => {
+    const entries = loadBundledMusicGenerationProviders();
     expect(entries.map((entry) => entry.pluginId).toSorted()).toEqual(
       expectedBundledMusicProviderPluginIds(),
     );
diff --git a/src/plugin-sdk/provider-web-search-contract.ts b/src/plugin-sdk/provider-web-search-contract.ts
index 2ab09acef52..17c09ea8778 100644
--- a/src/plugin-sdk/provider-web-search-contract.ts
+++ b/src/plugin-sdk/provider-web-search-contract.ts
@@ -1,12 +1,24 @@
-// Narrow shared exports for web-search contract surfaces.
-
-import type { WebSearchProviderPlugin } from "../plugins/types.js";
+// Public contract-safe web-search registration helpers for provider plugins.
 
+import type {
+  WebSearchCredentialResolutionSource,
+  WebSearchProviderSetupContext,
+  WebSearchProviderPlugin,
+  WebSearchProviderToolDefinition,
+} from "../plugins/types.js";
 export {
   getScopedCredentialValue,
+  getTopLevelCredentialValue,
+  mergeScopedSearchConfig,
   resolveProviderWebSearchPluginConfig,
   setScopedCredentialValue,
   setProviderWebSearchPluginConfigValue,
+  setTopLevelCredentialValue,
 } from "../agents/tools/web-search-provider-config.js";
 export { enablePluginInConfig } from "../plugins/enable.js";
-export type { WebSearchProviderPlugin };
+export type {
+  WebSearchCredentialResolutionSource,
+  WebSearchProviderSetupContext,
+  WebSearchProviderPlugin,
+  WebSearchProviderToolDefinition,
+};
diff --git a/test/helpers/media-generation/bundled-provider-builders.ts b/test/helpers/media-generation/bundled-provider-builders.ts
new file mode 100644
index 00000000000..88acbb38548
--- /dev/null
+++ b/test/helpers/media-generation/bundled-provider-builders.ts
@@ -0,0 +1,52 @@
+import { buildAlibabaVideoGenerationProvider } from "../../../extensions/alibaba/video-generation-provider.js";
+import { buildBytePlusVideoGenerationProvider } from "../../../extensions/byteplus/video-generation-provider.js";
+import { buildComfyMusicGenerationProvider } from "../../../extensions/comfy/music-generation-provider.js";
+import { buildComfyVideoGenerationProvider } from "../../../extensions/comfy/video-generation-provider.js";
+import { buildFalVideoGenerationProvider } from "../../../extensions/fal/video-generation-provider.js";
+import { buildGoogleMusicGenerationProvider } from "../../../extensions/google/music-generation-provider.js";
+import { buildGoogleVideoGenerationProvider } from "../../../extensions/google/video-generation-provider.js";
+import { buildMinimaxMusicGenerationProvider } from "../../../extensions/minimax/music-generation-provider.js";
+import { buildMinimaxVideoGenerationProvider } from "../../../extensions/minimax/video-generation-provider.js";
+import { buildOpenAIVideoGenerationProvider } from "../../../extensions/openai/video-generation-provider.js";
+import { buildQwenVideoGenerationProvider } from "../../../extensions/qwen/video-generation-provider.js";
+import { buildRunwayVideoGenerationProvider } from "../../../extensions/runway/video-generation-provider.js";
+import { buildTogetherVideoGenerationProvider } from "../../../extensions/together/video-generation-provider.js";
+import { buildVydraVideoGenerationProvider } from "../../../extensions/vydra/video-generation-provider.js";
+import { buildXaiVideoGenerationProvider } from "../../../extensions/xai/video-generation-provider.js";
+import type { MusicGenerationProvider } from "../../../src/music-generation/types.js";
+import type { VideoGenerationProvider } from "../../../src/video-generation/types.js";
+
+export type BundledVideoProviderEntry = {
+  pluginId: string;
+  provider: VideoGenerationProvider;
+};
+
+export type BundledMusicProviderEntry = {
+  pluginId: string;
+  provider: MusicGenerationProvider;
+};
+
+export function loadBundledVideoGenerationProviders(): BundledVideoProviderEntry[] {
+  return [
+    { pluginId: "alibaba", provider: buildAlibabaVideoGenerationProvider() },
+    { pluginId: "byteplus", provider: buildBytePlusVideoGenerationProvider() },
+    { pluginId: "comfy", provider: buildComfyVideoGenerationProvider() },
+    { pluginId: "fal", provider: buildFalVideoGenerationProvider() },
+    { pluginId: "google", provider: buildGoogleVideoGenerationProvider() },
+    { pluginId: "minimax", provider: buildMinimaxVideoGenerationProvider() },
+    { pluginId: "openai", provider: buildOpenAIVideoGenerationProvider() },
+    { pluginId: "qwen", provider: buildQwenVideoGenerationProvider() },
+    { pluginId: "runway", provider: buildRunwayVideoGenerationProvider() },
+    { pluginId: "together", provider: buildTogetherVideoGenerationProvider() },
+    { pluginId: "vydra", provider: buildVydraVideoGenerationProvider() },
+    { pluginId: "xai", provider: buildXaiVideoGenerationProvider() },
+  ];
+}
+
+export function loadBundledMusicGenerationProviders(): BundledMusicProviderEntry[] {
+  return [
+    { pluginId: "comfy", provider: buildComfyMusicGenerationProvider() },
+    { pluginId: "google", provider: buildGoogleMusicGenerationProvider() },
+    { pluginId: "minimax", provider: buildMinimaxMusicGenerationProvider() },
+  ];
+}