diff --git a/src/plugin-sdk/provider-web-search.ts b/src/plugin-sdk/provider-web-search.ts
index 551c3d5ed5d..33ccf1b62c7 100644
--- a/src/plugin-sdk/provider-web-search.ts
+++ b/src/plugin-sdk/provider-web-search.ts
@@ -1,12 +1,12 @@
 // Public web-search registration helpers for provider plugins.
 
+import type { WebSearchProviderPlugin } from "../plugins/types.js";
 export {
-  createPluginBackedWebSearchProvider,
   getScopedCredentialValue,
   getTopLevelCredentialValue,
   setScopedCredentialValue,
   setTopLevelCredentialValue,
-} from "../agents/tools/web-search-plugin-factory.js";
+} from "../agents/tools/web-search-provider-config.js";
 export { withTrustedWebToolsEndpoint } from "../agents/tools/web-guarded-fetch.js";
 export {
   DEFAULT_CACHE_TTL_MINUTES,
@@ -16,3 +16,21 @@ export {
   resolveCacheTtlMs,
   writeCache,
 } from "../agents/tools/web-shared.js";
+
+/**
+ * @deprecated Implement provider-owned `createTool(...)` directly on the
+ * returned WebSearchProviderPlugin instead of routing through core.
+ */
+export function createPluginBackedWebSearchProvider(
+  provider: WebSearchProviderPlugin,
+): WebSearchProviderPlugin {
+  return {
+    ...provider,
+    createTool: () => {
+      throw new Error(
+        `createPluginBackedWebSearchProvider(${provider.id}) is no longer supported. ` +
+          "Define provider-owned createTool(...) directly in the extension's WebSearchProviderPlugin.",
+      );
+    },
+  };
+}