diff --git a/frontend/src/features/agents/hooks/useAgentDrillDown.js b/frontend/src/features/agents/hooks/useAgentDrillDown.js
index db3e21a..46474d0 100644
--- a/frontend/src/features/agents/hooks/useAgentDrillDown.js
+++ b/frontend/src/features/agents/hooks/useAgentDrillDown.js
@@ -492,19 +492,25 @@
 
     const handleInjectOverride = async (e) => {
         if (e) e.preventDefault();
-        if (!overrideText.trim()) return;
+        const textToInject = overrideText.trim();
+        if (!textToInject) return;
         
+        // Optimistically update the UI to prevent "frozen" perception
+        setChatHistory(prev => [...prev, {
+            id: `temp-${Date.now()}`,
+            text: textToInject,
+            isUser: true,
+            sender: 'user',
+            timestamp: new Date().toISOString()
+        }]);
+        setOverrideText("");
+
         try {
             await fetchWithAuth(`/agents/${agentId}/run`, {
                 method: "POST",
-                body: { prompt: overrideText }
+                body: { prompt: textToInject }
             });
-            setModalConfig({ 
-                title: 'Task Injected', 
-                message: 'Manual task override has been sent to the agent.', 
-                type: 'success' 
-            });
-            setOverrideText("");
+            // We no longer show a modal for a successful injection, to mirror a smooth chat experience
             fetchData();
         } catch (err) {
             setModalConfig({ title: 'Injection Failed', message: err.message, type: 'error' });