diff --git a/mcp/packages/server/src/PluginBridge.sessions.test.ts b/mcp/packages/server/src/PluginBridge.sessions.test.ts
index 1a42241169..bc2d563602 100644
--- a/mcp/packages/server/src/PluginBridge.sessions.test.ts
+++ b/mcp/packages/server/src/PluginBridge.sessions.test.ts
@@ -169,3 +169,21 @@ test("a dashboard session remains routable while its workspace metadata changes"
         assert.deepEqual(bridge.getUserConnections("alice")!.getSessions(), [{ sessionId: "tab", ...context }]);
     }
 });
+
+test("a task fails at once when its plugin connection closes before answering", async () => {
+    const plugin = new WebSocket(`ws://127.0.0.1:${port}?userToken=alice`);
+    sockets.push(plugin);
+    await once(plugin, "open");
+    const initialized = once(plugin, "message");
+    plugin.send(JSON.stringify({ type: "initialize", session: { sessionId: "tab", fileId: null, fileName: null } }));
+    await initialized;
+    // the socket closes once the task reaches it
+    plugin.on("message", () => plugin.terminate());
+    const started = Date.now();
+    await assert.rejects(
+        bridge.executePluginTask(new PluginTask("test", {}), "tab"),
+        /connection closed before the task finished/
+    );
+    // well within the 1s task timeout of these tests
+    assert.ok(Date.now() - started < 500);
+});
diff --git a/mcp/packages/server/src/PluginBridge.ts b/mcp/packages/server/src/PluginBridge.ts
index 913b28b26a..127ef070d6 100644
--- a/mcp/packages/server/src/PluginBridge.ts
+++ b/mcp/packages/server/src/PluginBridge.ts
@@ -187,8 +187,8 @@ export class PluginBridge implements TaskDispatchHost {
                 }
             });
 
-            ws.on("close", () => {
-                this.logger.info("WebSocket connection closed");
+            ws.on("close", (code: number, reason: Buffer) => {
+                this.logger.info("WebSocket connection closed (code %d%s)", code, reason.length ? `: ${reason}` : "");
                 clearTimeout(initializationTimeout);
                 this.removeConnection(ws);
             });
@@ -262,8 +262,9 @@ export class PluginBridge implements TaskDispatchHost {
      *
      * Clears the per-connection keep-alive interval and removes the connection from the
      * socket-keyed index and the user's session collection. The token-keyed index entry
-     * is removed only when the user's last local connection closes. Safe to call with a
-     * socket that is not (or no longer) registered.
+     * is removed only when the user's last local connection closes. Tasks sent over the
+     * connection and still awaiting a response fail at once. Safe to call with a socket
+     * that is not (or no longer) registered.
      *
      * @param ws - The WebSocket whose connection state should be removed
      */
@@ -277,6 +278,13 @@ export class PluginBridge implements TaskDispatchHost {
         this.connectionsBySocket.delete(ws);
         const connections = this.getUserConnections(connection.userToken)!;
         connections.remove(connection);
+        // a task sent over the closed socket can no longer be answered, since responses only count
+        // from the connection the task went to
+        for (const [taskId, taskConnection] of [...this.taskConnections]) {
+            if (taskConnection === connection) {
+                this.rejectPendingTask(taskId, new Error("The plugin connection closed before the task finished."));
+            }
+        }
         if (connection.userToken !== null && connections.size === 0) {
             this.userPenpotConnectionsByToken.delete(connection.userToken);
         }