fix(discord): use ws for gateway sockets

extensions/discord/src/monitor/gateway-plugin.ts

@@ -270,11 +270,22 @@ function createGatewayPlugin(params: {
     }
 
     override createWebSocket(url: string) {
-      if (!params.wsAgent) {
-        return super.createWebSocket(url);
+      if (!url) {
+        throw new Error("Gateway URL is required");
       }
+      // Avoid Node's undici-backed global WebSocket here. We have seen late
+      // close-path crashes during Discord gateway teardown; the ws transport is
+      // already our proxy path and behaves predictably for lifecycle cleanup.
       const WebSocketCtor = params.testing?.webSocketCtor ?? ws.default;
-      return new WebSocketCtor(url, { agent: params.wsAgent });
+      const socket = new WebSocketCtor(url, params.wsAgent ? { agent: params.wsAgent } : undefined);
+      if ("binaryType" in socket) {
+        try {
+          socket.binaryType = "arraybuffer";
+        } catch {
+          // Ignore runtimes that expose a readonly binaryType.
+        }
+      }
+      return socket;
     }
   }
 

extensions/discord/src/monitor/provider.proxy.test.ts

@@ -244,6 +244,21 @@ describe("createDiscordGatewayPlugin", () => {
     expect(baseRegisterClientSpy).toHaveBeenCalledTimes(1);
   });
 
+  it("uses ws for gateway sockets even without proxy", () => {
+    const runtime = createRuntime();
+    const plugin = createDiscordGatewayPlugin({
+      discordConfig: {},
+      runtime,
+    });
+
+    const createWebSocket = (plugin as unknown as { createWebSocket: (url: string) => unknown })
+      .createWebSocket;
+    createWebSocket("wss://gateway.discord.gg");
+
+    expect(webSocketSpy).toHaveBeenCalledWith("wss://gateway.discord.gg", undefined);
+    expect(wsProxyAgentSpy).not.toHaveBeenCalled();
+  });
+
   it("maps plain-text Discord 503 responses to fetch failed", async () => {
     await expectGatewayRegisterFallback({
       ok: false,