diff --git a/webui/src/components/thread/ThreadComposer.tsx b/webui/src/components/thread/ThreadComposer.tsx
index e2967f2b..e1d7d0a4 100644
--- a/webui/src/components/thread/ThreadComposer.tsx
+++ b/webui/src/components/thread/ThreadComposer.tsx
@@ -90,8 +90,37 @@ import { cn } from "@/lib/utils";
 const ACCEPT_ATTR = "image/png,image/jpeg,image/webp,image/gif";
 const VOICE_SHORTCUT_CODE = "KeyD";
 const VOICE_SHORTCUT_ARIA = "Control+Shift+D";
+const FALLBACK_SIDE_CHANNEL_COMMANDS = new Set([
+  "/new",
+  "/stop",
+  "/restart",
+  "/status",
+  "/model",
+  "/history",
+  "/goal",
+  "/trigger",
+  "/dream",
+  "/dream-log",
+  "/dream-restore",
+  "/dream-prompt",
+  "/skill",
+  "/help",
+  "/pairing",
+]);
 type VoiceShortcutPlatform = "apple" | "chromeos" | "linux" | "other" | "windows";
 
+function isSlashCommandSideChannel(content: string, visibleSlashCommands: SlashCommand[]): boolean {
+  const commandName = content.split(/\s+/, 1)[0];
+  if (!commandName.startsWith("/")) return false;
+  if (commandName === "/goal" && content.slice(commandName.length).trim().length > 0) {
+    return false;
+  }
+  return (
+    FALLBACK_SIDE_CHANNEL_COMMANDS.has(commandName)
+    || visibleSlashCommands.some((command) => command.command === commandName)
+  );
+}
+
 function formatBytes(n: number): string {
   if (n < 1024) return `${n} B`;
   if (n < 1024 * 1024) return `${(n / 1024).toFixed(1)} KB`;
@@ -1480,12 +1509,11 @@ export function ThreadComposer({
             ...(attachedMcpPresets.length > 0 ? { mcpPresets: attachedMcpPresets } : {}),
           }
         : undefined;
-    const commandName = content.split(/\s+/, 1)[0];
     const isSlashSideChannel =
       payload === undefined
       && attachedCliApps.length === 0
       && attachedMcpPresets.length === 0
-      && visibleSlashCommands.some((command) => command.command === commandName);
+      && isSlashCommandSideChannel(content, visibleSlashCommands);
     onSend(
       content,
       payload,
diff --git a/webui/src/tests/thread-composer.test.tsx b/webui/src/tests/thread-composer.test.tsx
index f4d27039..b0459e32 100644
--- a/webui/src/tests/thread-composer.test.tsx
+++ b/webui/src/tests/thread-composer.test.tsx
@@ -1329,6 +1329,51 @@ describe("ThreadComposer", () => {
     expect(onSend).toHaveBeenCalledWith("/history", undefined, { sideChannel: true });
   });
 
+  it("marks builtin slash commands as side-channel sends before command metadata loads", () => {
+    const onSend = vi.fn();
+    render(
+      <ThreadComposer
+        onSend={onSend}
+        placeholder="Type your message..."
+      />,
+    );
+
+    const input = screen.getByLabelText("Message input");
+    fireEvent.change(input, { target: { value: "/status" } });
+    fireEvent.click(screen.getByRole("button", { name: "Send message" }));
+
+    expect(onSend).toHaveBeenCalledWith("/status", undefined, { sideChannel: true });
+  });
+
+  it("keeps goal task commands on the normal agent turn path", () => {
+    const onSend = vi.fn();
+    render(
+      <ThreadComposer
+        onSend={onSend}
+        placeholder="Type your message..."
+        slashCommands={[
+          {
+            command: "/goal",
+            title: "Start long-running goal",
+            description: "Tell the agent to treat the request as a long-running goal.",
+            icon: "activity",
+            argHint: "<goal>",
+          },
+        ]}
+      />,
+    );
+
+    const input = screen.getByLabelText("Message input");
+    fireEvent.change(input, { target: { value: "/goal fix the release blocker" } });
+    fireEvent.click(screen.getByRole("button", { name: "Send message" }));
+
+    expect(onSend).toHaveBeenCalledWith(
+      "/goal fix the release blocker",
+      undefined,
+      undefined,
+    );
+  });
+
   it("shows a stop button while streaming", () => {
     const onStop = vi.fn();
     render(