diff --git a/packages/react-ai-sdk/src/rsc/VercelRSCRuntime.tsx b/packages/react-ai-sdk/src/rsc/VercelRSCRuntime.tsx
index 2aae5e891..711d3062b 100644
--- a/packages/react-ai-sdk/src/rsc/VercelRSCRuntime.tsx
+++ b/packages/react-ai-sdk/src/rsc/VercelRSCRuntime.tsx
@@ -36,14 +36,8 @@ export class VercelRSCRuntime<
     return () => {};
   }
 
-  public switchToThread(threadId: string | null) {
-    if (threadId) {
-      throw new Error(
-        "VercelRSCRuntime does not yet support switching threads",
-      );
-    }
-
-    this.thread = new VercelRSCThreadRuntime(this.thread.adapter);
+  public switchToThread() {
+    throw new Error("VercelRSCRuntime does not support switching threads");
   }
 }
 
diff --git a/packages/react-ai-sdk/src/ui/VercelAIRuntime.tsx b/packages/react-ai-sdk/src/ui/VercelAIRuntime.tsx
index b0bb18ba7..3185d0575 100644
--- a/packages/react-ai-sdk/src/ui/VercelAIRuntime.tsx
+++ b/packages/react-ai-sdk/src/ui/VercelAIRuntime.tsx
@@ -1,6 +1,10 @@
-import type { ReactThreadRuntime, Unsubscribe } from "@assistant-ui/react";
-import type { AppendMessage, ThreadMessage } from "@assistant-ui/react";
-import { INTERNAL } from "@assistant-ui/react";
+import {
+  type ReactThreadRuntime,
+  type Unsubscribe,
+  type AppendMessage,
+  type ThreadMessage,
+  INTERNAL,
+} from "@assistant-ui/react";
 import type { Message } from "ai";
 import { type StoreApi, type UseBoundStore, create } from "zustand";
 import { getVercelAIMessage } from "./getVercelAIMessage";
@@ -39,6 +43,12 @@ export class VercelAIRuntime extends BaseAssistantRuntime<VercelAIThreadRuntime>
       throw new Error("VercelAIRuntime does not yet support switching threads");
     }
 
+    // clear the vercel state (otherwise, it will be captured by the MessageRepository)
+    this.thread.vercel.messages = [];
+    this.thread.vercel.input = "";
+    this.thread.vercel.setMessages([]);
+    this.thread.vercel.setInput("");
+
     this.thread = new VercelAIThreadRuntime(this.thread.vercel);
   }
 }