What happened?

Environment:

• OS: Windows (win32)
• Gemini CLI Version: 0.34.0
  Description:
  Starting with version 0.34.0, using tab autocomplete for subcommands results in the main command name being duplicated instead of the subcommand being inserted. This happens with multiple commands that have subcommands.
  Steps to Reproduce:

1. Type /ch in the CLI.
2. Press Tab to autocomplete. The input correctly becomes /chat .
3. Type r (intending to autocomplete the resume subcommand).
4. Press Tab.
   Expected Behavior:
   The autocomplete should complete the subcommand, resulting in /chat resume.
   Actual Behavior:
   The autocomplete duplicates the main command, resulting in /chat chat.
   Additional Context:
   This issue is not limited to /chat resume. It also happens with other commands and their subcommands, for example resulting in /save save instead of the expected subcommand.

[ACTION REQUIRED] 📎 PLEASE ATTACH THE EXPORTED CHAT HISTORY JSON FILE TO THIS ISSUE IF YOU FEEL COMFORTABLE SHARING IT.

What did you expect to happen?

/chat resume

Client information

• CLI Version: 0.34.0
• Git Commit: 49a8655
• Session ID: 964a2664-37c3-44d2-bbc8-324ca03052c2
• Operating System: win32 v25.8.1
• Sandbox Environment: no sandbox
• Model Version: gemini-3.1-pro-preview
• Auth Type: oauth-personal
• Memory Usage: 313.1 MB
• Terminal Name: Unknown
• Terminal Background: #0c0c0c
• Kitty Keyboard Protocol: Unsupported

Login information

Oauth web

Anything else we need to know?

No response