diff --git a/src/client/stdio.test.ts b/src/client/stdio.test.ts
index 8c3786eb..2e4d92c2 100644
--- a/src/client/stdio.test.ts
+++ b/src/client/stdio.test.ts
@@ -1,5 +1,14 @@
 import { JSONRPCMessage } from "../types.js";
-import { StdioClientTransport, getDefaultServerParameters } from "./stdio.js";
+import { StdioClientTransport, StdioServerParameters } from "./stdio.js";
+
+// Configure default server parameters based on OS
+// Uses 'more' command for Windows and 'tee' command for Unix/Linux
+const getDefaultServerParameters = (): StdioServerParameters => {
+  if (process.platform === "win32") {
+    return { command: "more" };
+  }
+  return { command: "/usr/bin/tee" };
+};
 
 const serverParameters = getDefaultServerParameters();
 
diff --git a/src/client/stdio.ts b/src/client/stdio.ts
index a34e8f19..62292ce1 100644
--- a/src/client/stdio.ts
+++ b/src/client/stdio.ts
@@ -39,15 +39,6 @@ export type StdioServerParameters = {
   cwd?: string;
 };
 
-// Configure default server parameters based on OS
-// Uses 'more' command for Windows and 'tee' command for Unix/Linux
-export const getDefaultServerParameters = (): StdioServerParameters => {
-  if (process.platform === "win32") {
-    return { command: "more" };
-  }
-  return { command: "/usr/bin/tee" };
-};
-
 /**
  * Environment variables to inherit by default, if an environment is not explicitly given.
  */
diff --git a/src/inMemory.test.ts b/src/inMemory.test.ts
index 0b0d5fe5..baf43446 100644
--- a/src/inMemory.test.ts
+++ b/src/inMemory.test.ts
@@ -96,43 +96,10 @@ describe("InMemoryTransport", () => {
   });
 
   test("should throw error when sending after close", async () => {
-    const [client, server] = InMemoryTransport.createLinkedPair();
-    let clientError: Error | undefined;
-    let serverError: Error | undefined;
-
-    client.onerror = (err) => {
-      clientError = err;
-    };
-
-    server.onerror = (err) => {
-      serverError = err;
-    };
-
-    await client.close();
-
-    // Attempt to send message from client
+    await clientTransport.close();
     await expect(
-      client.send({
-        jsonrpc: "2.0",
-        method: "test",
-        id: 1,
-      }),
+      clientTransport.send({ jsonrpc: "2.0", method: "test", id: 1 }),
     ).rejects.toThrow("Not connected");
-
-    // Attempt to send message from server
-    await expect(
-      server.send({
-        jsonrpc: "2.0",
-        method: "test",
-        id: 2,
-      }),
-    ).rejects.toThrow("Not connected");
-
-    // Verify that both sides received errors
-    expect(clientError).toBeDefined();
-    expect(clientError?.message).toBe("Not connected");
-    expect(serverError).toBeDefined();
-    expect(serverError?.message).toBe("Not connected");
   });
 
   test("should queue messages sent before start", async () => {
@@ -151,65 +118,4 @@ describe("InMemoryTransport", () => {
     await serverTransport.start();
     expect(receivedMessage).toEqual(message);
   });
-
-  describe("error handling", () => {
-    test("should trigger onerror when sending without connection", async () => {
-      const transport = new InMemoryTransport();
-      let error: Error | undefined;
-
-      transport.onerror = (err) => {
-        error = err;
-      };
-
-      await expect(
-        transport.send({
-          jsonrpc: "2.0",
-          method: "test",
-          id: 1,
-        }),
-      ).rejects.toThrow("Not connected");
-
-      expect(error).toBeDefined();
-      expect(error?.message).toBe("Not connected");
-    });
-
-    test("should trigger onerror when sending after close", async () => {
-      const [client, server] = InMemoryTransport.createLinkedPair();
-      let clientError: Error | undefined;
-      let serverError: Error | undefined;
-
-      client.onerror = (err) => {
-        clientError = err;
-      };
-
-      server.onerror = (err) => {
-        serverError = err;
-      };
-
-      await client.close();
-
-      // Attempt to send message from client
-      await expect(
-        client.send({
-          jsonrpc: "2.0",
-          method: "test",
-          id: 1,
-        }),
-      ).rejects.toThrow("Not connected");
-
-      // Attempt to send message from server
-      await expect(
-        server.send({
-          jsonrpc: "2.0",
-          method: "test",
-          id: 2,
-        }),
-      ).rejects.toThrow("Not connected");
-
-      // Verify that both sides received errors
-      expect(clientError?.message).toBe("Not connected");
-      expect(serverError).toBeDefined();
-      expect(serverError?.message).toBe("Not connected");
-    });
-  });
 });
diff --git a/src/inMemory.ts b/src/inMemory.ts
index 056a4718..5dd6e81e 100644
--- a/src/inMemory.ts
+++ b/src/inMemory.ts
@@ -51,9 +51,7 @@ export class InMemoryTransport implements Transport {
    */
   async send(message: JSONRPCMessage, options?: { relatedRequestId?: RequestId, authInfo?: AuthInfo }): Promise<void> {
     if (!this._otherTransport) {
-      const error = new Error("Not connected");
-      this.onerror?.(error);
-      throw error;
+      throw new Error("Not connected");
     }
 
     if (this._otherTransport.onmessage) {