diff --git a/apps/frontend/src/main/task-state-manager.ts b/apps/frontend/src/main/task-state-manager.ts
index fffb7beab0..b26c23a1ff 100644
--- a/apps/frontend/src/main/task-state-manager.ts
+++ b/apps/frontend/src/main/task-state-manager.ts
@@ -362,17 +362,22 @@ export class TaskStateManager {
 
     const phase = XSTATE_TO_PHASE[xstateState] || 'idle';
 
-    // Emit execution progress with the phase derived from XState
+    // Emit execution progress with the phase derived from XState.
+    // IMPORTANT: Do NOT use Date.now() as sequenceNumber here — doing so would
+    // permanently block all subsequent agent execution-progress events, because
+    // the agent uses small sequential integers (1, 2, 3…) that are always less
+    // than a timestamp. Instead emit with sequenceNumber=0 so the agent's own
+    // events can continue updating phaseProgress once the phase is established.
     safeSendToRenderer(
       this.getMainWindow,
       IPC_CHANNELS.TASK_EXECUTION_PROGRESS,
       taskId,
       {
         phase,
-        phaseProgress: phase === 'complete' ? 100 : 50,
-        overallProgress: phase === 'complete' ? 100 : 50,
+        phaseProgress: phase === 'complete' ? 100 : 0,
+        overallProgress: phase === 'complete' ? 100 : 0,
         message: `State: ${xstateState}`,
-        sequenceNumber: Date.now()  // Use timestamp as sequence to ensure it's newer
+        sequenceNumber: 0
       },
       projectId
     );