TUI can auto-submit whitespace prompt, creating “empty user message” and breaking Claude/OpenAI-compatible proxies

[breeze0015]

Description

OpenCode sometimes sends a “user sent an empty message” even when I did not manually submit anything. This can also trigger upstream errors (e.g., Claude/Bedrock: messages: text content blocks must be non-empty) when using OpenAI-compatible proxy layers that translate requests to Anthropic format.

Plugins

No response

OpenCode version

1.1.21

Steps to reproduce

1. Start OpenCode TUI with a whitespace-only prompt, for example:
   • opencode --prompt " "
   • or opencode --prompt "\n"
2. Observe that OpenCode auto-submits the prompt on startup and a user message is created even though it contains only whitespace.

Screenshot and/or share link

https://opncd.ai/share/32IIf93w

Operating System

Windows 10

Terminal

opencode-desktop-windows-x64.exe

[github-actions]

This issue might be a duplicate of existing issues. Please check:

• when (mistakenly) sending empty message the session stop with the error: text cannot be empty. #7493: when (mistakenly) sending empty message the session stop with the error: text cannot be empty.
• TUI: Prompt gets submitted when switching sessions #8019: TUI: Prompt gets submitted when switching sessions
• moving between different sessions while having a non submited prompt from the user executes the command in the session we move to #8196: moving between different sessions while having a non submitted prompt from the user executes the command in the session we move to

Feel free to ignore if none of these address your specific case.