From e46bd055944788f42fb8ada0df38a2165ecbd5ee Mon Sep 17 00:00:00 2001
From: Mahima Shanware <mahima.shanware@gmail.com>
Date: Tue, 28 Apr 2026 21:16:35 +0000
Subject: [PATCH] feat(cli): fix UserSimulator deadlock on static screens by
 tracking composite state

---
 .../cli/src/services/UserSimulator.test.ts    | 39 +++++++++++++++++++
 packages/cli/src/services/UserSimulator.ts    | 18 +++++----
 2 files changed, 50 insertions(+), 7 deletions(-)

diff --git a/packages/cli/src/services/UserSimulator.test.ts b/packages/cli/src/services/UserSimulator.test.ts
index 9e4249006d..d5fd89c2f0 100644
--- a/packages/cli/src/services/UserSimulator.test.ts
+++ b/packages/cli/src/services/UserSimulator.test.ts
@@ -189,4 +189,43 @@ describe('UserSimulator', () => {
     expect(mockMessageBus.unsubscribe).toHaveBeenCalled();
     vi.useRealTimers();
   });
+
+  it('should re-evaluate if internal tool state changes even if screen content is static', async () => {
+    const simulator = new UserSimulator(
+      mockConfig,
+      mockGetScreen,
+      mockStdinBuffer,
+    );
+    mockGetScreen.mockReturnValue('Responding...');
+
+    vi.useFakeTimers();
+    simulator.start();
+
+    // Trigger first tick
+    await vi.advanceTimersByTimeAsync(2000);
+    expect(mockContentGenerator.generateContent).toHaveBeenCalledTimes(1);
+
+    // Trigger second tick with same screen - should skip
+    await vi.advanceTimersByTimeAsync(2000);
+    expect(mockContentGenerator.generateContent).toHaveBeenCalledTimes(1);
+
+    // Simulate tool call update
+    const handler = mockMessageBus.subscribe.mock.calls[0][1];
+    handler({
+      type: MessageBusType.TOOL_CALLS_UPDATE,
+      toolCalls: [
+        {
+          status: CoreToolCallStatus.AwaitingApproval,
+          request: { callId: '123', name: 'test_tool' },
+        },
+      ],
+    });
+
+    // Trigger third tick with same screen but new tool state - should NOT skip
+    await vi.advanceTimersByTimeAsync(2000);
+    expect(mockContentGenerator.generateContent).toHaveBeenCalledTimes(2);
+
+    simulator.stop();
+    vi.useRealTimers();
+  });
 });
diff --git a/packages/cli/src/services/UserSimulator.ts b/packages/cli/src/services/UserSimulator.ts
index 4635ffb931..540dea801a 100644
--- a/packages/cli/src/services/UserSimulator.ts
+++ b/packages/cli/src/services/UserSimulator.ts
@@ -28,7 +28,7 @@ interface SimulatorResponse {
 export class UserSimulator {
   private isRunning = false;
   private timer: NodeJS.Timeout | null = null;
-  private lastScreenContent = '';
+  private lastStateKey = '';
   private isProcessing = false;
   private interactionsFile: string | null = null;
 
@@ -131,7 +131,16 @@ export class UserSimulator {
         .replace(/\(\s*\)/g, '')
         .trim();
 
-      if (normalizedScreen === this.lastScreenContent) return;
+      // Create a composite key representing the full state (Vision + Internal State)
+      const pendingIds = this.pendingToolCalls
+        .map((tc) => tc.request.callId)
+        .join(',');
+      const currentStateKey = `${normalizedScreen}::${pendingIds}`;
+
+      if (currentStateKey === this.lastStateKey) {
+        return;
+      }
+      this.lastStateKey = currentStateKey;
 
       debugLogger.log(
         `[SIMULATOR] Screen Content Seen:\n---\n${strippedScreen}\n---`,
@@ -304,7 +313,6 @@ ${strippedScreen}
             `[LOG] [SIMULATOR] Action History updated with: "<WAIT>"\n\n`,
           );
         }
-        this.lastScreenContent = normalizedScreen;
         return;
       }
 
@@ -364,8 +372,6 @@ ${strippedScreen}
 
         // Wait a bit to ensure Ink has processed the full input
         await new Promise((resolve) => setTimeout(resolve, 100));
-
-        this.lastScreenContent = normalizedScreen;
       } else {
         debugLogger.log('[SIMULATOR] Skipping (empty response)');
 
@@ -376,8 +382,6 @@ ${strippedScreen}
             `[LOG] [SIMULATOR] Action History updated with: "<EMPTY>"\n\n`,
           );
         }
-
-        this.lastScreenContent = normalizedScreen;
       }
     } catch (e: unknown) {
       debugLogger.error('UserSimulator tick failed', e);