From 115c4981a672c4d0896abffb0f00d8431166db31 Mon Sep 17 00:00:00 2001
From: Hermes Agent <hermes-agent@offis-rit.github.io>
Date: Mon, 22 Jun 2026 14:53:09 +0200
Subject: [PATCH 1/2] feat(frontend): add stop button to cancel streaming
 response

- Add stop() from useChat to destructure
- Add conditional Stop button visible only while isAssistantTyping
- Stop button replaces send button during streaming
- Call stop() on click to cancel the AI response

Closes #484
---
 apps/frontend/components/chat/ProjectChat.tsx | 43 ++++++++++++-------
 1 file changed, 27 insertions(+), 16 deletions(-)

diff --git a/apps/frontend/components/chat/ProjectChat.tsx b/apps/frontend/components/chat/ProjectChat.tsx
index c77a8996..b5209ded 100644
--- a/apps/frontend/components/chat/ProjectChat.tsx
+++ b/apps/frontend/components/chat/ProjectChat.tsx
@@ -37,6 +37,7 @@ import {
     MicOff,
     RotateCcw,
     SendIcon,
+    Square,
     Volume2,
     VolumeX,
     X,
@@ -512,7 +513,7 @@ function ProjectChatSession({
         }
     }, [selectedModelId, selectableModels]);
 
-    const { messages, sendMessage, status, addToolOutput } = useChat<ChatUIMessage>({
+    const { messages, sendMessage, status, addToolOutput, stop } = useChat<ChatUIMessage>({
         chat: entry.chat,
     });
 
@@ -915,21 +916,31 @@ function ProjectChatSession({
                             {isRecording ? <MicOff className="h-4 w-4" /> : <Mic className="h-4 w-4" />}
                         </Button>
                     )}
-                    <Button
-                        size="icon"
-                        onClick={() => void handleSendMessage()}
-                        disabled={
-                            !inputValue.trim() ||
-                            isAssistantTyping ||
-                            isRecording ||
-                            !!pendingClarification ||
-                            noModelsConfigured
-                        }
-                        className={isEmptyChat ? "h-10 w-10 shrink-0" : undefined}
-                    >
-                        <SendIcon className="h-4 w-4" />
-                        <span className="sr-only">{t("send.message")}</span>
-                    </Button>
+                    {isAssistantTyping ? (
+                        <Button
+                            size="icon"
+                            onClick={() => stop()}
+                            className={isEmptyChat ? "h-10 w-10 shrink-0" : undefined}
+                        >
+                            <Square className="h-4 w-4" />
+                            <span className="sr-only">{t("stop.response")}</span>
+                        </Button>
+                    ) : (
+                        <Button
+                            size="icon"
+                            onClick={() => void handleSendMessage()}
+                            disabled={
+                                !inputValue.trim() ||
+                                isRecording ||
+                                !!pendingClarification ||
+                                noModelsConfigured
+                            }
+                            className={isEmptyChat ? "h-10 w-10 shrink-0" : undefined}
+                        >
+                            <SendIcon className="h-4 w-4" />
+                            <span className="sr-only">{t("send.message")}</span>
+                        </Button>
+                    )}
                 </div>
             </div>
         </div>

From 3ec0d87c08a903b85a53c69f0d53494205c50d2b Mon Sep 17 00:00:00 2001
From: Hermes Agent <hermes-agent@offis-rit.github.io>
Date: Mon, 22 Jun 2026 15:02:33 +0200
Subject: [PATCH 2/2] fix(frontend): add missing stop.response i18n key for
 stop button accessibility

---
 apps/frontend/messages/de.json | 1 +
 apps/frontend/messages/en.json | 1 +
 2 files changed, 2 insertions(+)

diff --git a/apps/frontend/messages/de.json b/apps/frontend/messages/de.json
index 8c6c0744..24ea0c60 100644
--- a/apps/frontend/messages/de.json
+++ b/apps/frontend/messages/de.json
@@ -91,6 +91,7 @@
     "copied.code": "Code kopiert",
     "start.recording": "Spracheingabe starten",
     "stop.recording": "Spracheingabe beenden",
+    "stop.response": "Antwort stoppen",
     "play.message": "Abspielen",
     "stop.speaking": "Stopp",
     "deep.mode": "Tiefe Analyse",
diff --git a/apps/frontend/messages/en.json b/apps/frontend/messages/en.json
index 14656ab3..35e2f248 100644
--- a/apps/frontend/messages/en.json
+++ b/apps/frontend/messages/en.json
@@ -91,6 +91,7 @@
     "copied.code": "Code copied",
     "start.recording": "Start voice input",
     "stop.recording": "Stop voice input",
+    "stop.response": "Stop response",
     "play.message": "Play",
     "stop.speaking": "Stop",
     "deep.mode": "Deep Mode",