[BUG] Prompt suggestion replaces existing prompt

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Typing out a big prompt, accidentally pressed tab, and the "prompt suggestion" feature wiped my prompt and replaced it with the suggestion.

Minimal example:

!Image

What Should Happen?

Only accept the default suggestion if the prompt input is empty

Error Messages/Logs

Steps to Reproduce

1. Wait until the UI shows a prompt suggestion
2. Type your own prompt
3. Hit tab, see it get replaced

Claude Model

None

Is this a regression?

No, this never worked

Last Working Version

_No response_

Claude Code Version

2.0.69

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

iTerm2

Additional Information

_No response_