Plan mode re-sends the "Start with Auto Copilot" command after switching back from Agent mode, causing duplicate execution and extra credit consumption

[YOLOthemotto]

Description

I found a reproducible issue when using the Plan and Agent workflow.

Steps to Reproduce

1. Open Copilot Chat.
2. Switch to Plan mode.
3. Ask Copilot to generate an implementation plan.
4. After the plan is generated, click Start with Auto Copilot.
5. Wait until Auto Copilot finishes executing all tasks.
6. Switch from Agent mode back to Plan mode.

Expected Behavior

Switching back to Plan mode should simply display the completed plan and allow me to continue planning or make changes. No additional action should be triggered automatically.

Actual Behavior

As soon as I switch back to Plan mode, Copilot automatically sends the previous "Start with Auto Copilot" implementation request again, causing the implementation process to be triggered a second time.

This happens even though the previous Auto Copilot task has already completed successfully.

Impact

This issue has two negative effects:

• The implementation is executed twice unnecessarily.
• The unintended second execution also consumes additional AI credits.

Because the second execution is triggered automatically when switching back to Plan mode, there is no opportunity to cancel it beforehand. This can lead to unnecessary credit usage and may quickly consume a user's available quota.

Environment

• VS Code Version: 1.127.0 (Universal)
• Commit: 4fe60c8
• Date: 2026-06-30T10:52:33+02:00
• Electron: 42.2.0
• Electron Build ID: 14159160
• Chromium: 148.0.7778.97
• Node.js: 24.15.0
• V8: 14.8.178.14-electron.0
• OS: macOS 13.6 (Darwin x64 22.6.0)

Additional Notes

It appears that switching back to Plan mode replays or re-executes the previous "Start with Auto Copilot" action instead of simply restoring the completed planning session.

In my opinion, switching between Plan and Agent modes should not automatically trigger any new execution. It should only restore the previous conversation state unless the user explicitly starts a new Auto Copilot run.

I can provide a screen recording if that would help reproduce the issue.

[iuuuuuuu7]

I can reproduce a very similar issue on Windows.

Additional Repro Case

After an implementation task completes, clicking the back/return button does not simply return to the previous Plan/Chat state. Instead, VS Code opens/creates a new chat window/session and automatically sends:

Start implementation