[BUG] agent-Plan produces a plan but doesn't allow user to see it

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?

When using @agent-Plan, the agent shows a notice to use /plan to look at the plan, and then asks clarifying questions, but the user can't preview the plan using the /plan command while the agent is working as any user messages are queued till after planning, therefore the user doesn't have the context they need to answer the questions.

What Should Happen?

Claude should display a summary, and allow user to see the full plan with the slash command BEFORE asking clarifying questions

Error Messages/Logs

Steps to Reproduce

1. Call @agent-Plan
2. Claude produces a plan
3. Claude says "/plan to preview the plan"
4. Attempt to do so now becomes a queued message
5. Claude asks clarifying questions

Claude Model

Sonnet (default)

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.0.76 (Claude Code)

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Warp

Additional Information

_No response_