From 72598322d14992004c8ede446ef919573ebf41c7 Mon Sep 17 00:00:00 2001
From: Naiyuan Qing <145280634+NevilleQingNY@users.noreply.github.com>
Date: Fri, 6 Feb 2026 19:35:39 +0800
Subject: [PATCH] feat(desktop): handle agent_error events and clearLastRoute
 in IPC

Forward agent_error as passthrough event to renderer. Add
clearLastRoute() calls in hub:sendMessage and localChat:send
handlers so channel replies stop when desktop sends a message.
Handle agent_error in use-local-chat to show error UI.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
---
 apps/desktop/electron/ipc/hub.ts         | 12 +++++++-----
 apps/desktop/src/hooks/use-local-chat.ts |  8 ++++++++
 2 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/apps/desktop/electron/ipc/hub.ts b/apps/desktop/electron/ipc/hub.ts
index b038efe8..288c4ef0 100644
--- a/apps/desktop/electron/ipc/hub.ts
+++ b/apps/desktop/electron/ipc/hub.ts
@@ -236,6 +236,7 @@ export function registerHubIpcHandlers(): void {
     if (agent.closed) {
       return { error: `Agent is closed: ${agentId}` }
     }
+    h.channelManager.clearLastRoute()
     agent.write(content)
     return { ok: true }
   })
@@ -268,11 +269,11 @@ export function registerHubIpcHandlers(): void {
         return
       }
 
-      // Compaction events: forward with no stream tracking
-      const isCompactionEvent =
-        event.type === 'compaction_start' || event.type === 'compaction_end'
-      if (isCompactionEvent) {
-        safeLog(`[IPC] Sending compaction event to renderer: ${event.type}`)
+      // Compaction and error events: forward with no stream tracking
+      const isPassthroughEvent =
+        event.type === 'compaction_start' || event.type === 'compaction_end' || event.type === 'agent_error'
+      if (isPassthroughEvent) {
+        safeLog(`[IPC] Sending ${event.type} event to renderer`)
         mainWindowRef.webContents.send('localChat:event', {
           agentId,
           streamId: null,
@@ -384,6 +385,7 @@ export function registerHubIpcHandlers(): void {
       return { error: 'Not subscribed to agent events. Call subscribe first.' }
     }
 
+    h.channelManager.clearLastRoute()
     agent.write(content)
     safeLog(`[IPC] Local chat message sent to agent: ${agentId}`)
     return { ok: true }
diff --git a/apps/desktop/src/hooks/use-local-chat.ts b/apps/desktop/src/hooks/use-local-chat.ts
index cf637f25..ec7e9677 100644
--- a/apps/desktop/src/hooks/use-local-chat.ts
+++ b/apps/desktop/src/hooks/use-local-chat.ts
@@ -56,6 +56,14 @@ export function useLocalChat() {
       const payload = data as unknown as StreamPayload
       if (!payload.event) return
 
+      // Handle agent errors as transient UI feedback (not persisted to history)
+      if (payload.event.type === 'agent_error') {
+        const errorMsg = (payload.event as { error?: string }).error ?? 'Unknown error'
+        chatRef.current.setError({ code: 'AGENT_ERROR', message: errorMsg })
+        setIsLoading(false)
+        return
+      }
+
       chatRef.current.handleStream(payload)
       if (payload.event.type === 'message_start') setIsLoading(true)
       if (payload.event.type === 'message_end') setIsLoading(false)