[Feature Request] Expose ExitPlanMode interactive menu for custom slash commands

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

When /plan mode finishes, Claude presents a native interactive menu that lets you clear context and execute — in one click, zero copy-paste. This is one of the most powerful UX patterns in Claude Code because it separates the noisy planning context from clean execution.
Custom slash commands have no equivalent. When my command finishes generating a plan or structured output, I'm stuck — I have to manually copy the output, run /clear, and re-paste it as a new prompt. This breaks the flow entirely and defeats the purpose of having a command.

Proposed Solution

Expose a frontmatter option in skill/command files that declares the output as "executable" — triggering the same native ExitPlanMode interactive menu (clear context + execute options) after the command finishes.
Something like:
yaml---
name: my-plan
description: My custom planning flow
exit-mode: plan # triggers the ExitPlanMode interactive menu
---
This wouldn't require new UI — just reuse the existing ExitPlanMode flow that's already built. The command output would be treated as the plan, and the user gets the same one-click "clear context & execute" experience they already love from /plan.

Alternative Solutions

The best workaround found after research is a manual 3-step process:

Run the custom slash command and wait for the output
Manually copy the output (or save it to a file like .claude/current-plan.md)
Run /clear to reset context, then paste the output or reference the file as a new prompt

This is fundamentally broken compared to the native plan mode experience because:

It's manual — requires the user to context-switch, copy, clear, and re-paste every single time
It breaks flow — the whole point of a slash command is to automate repetitive steps, but the most critical step (clean execution) still requires manual intervention
It's error-prone — easy to forget to clear, or lose part of the output during copy-paste
It's not equivalent — plan mode doesn't just clear and paste, it carries the plan file into the fresh context in a structured way. A manual paste is a degraded version of that
No auto-accept transition — the native menu also lets you go straight into auto-accept edits mode. There's no manual equivalent of that without changing permission mode separately via Shift+Tab

The native /plan flow does all of this atomically in one keypress. Custom commands have no path to that experience today.

Priority

High - Significant impact on productivity

Feature Category

Interactive mode (TUI)

Use Case Example

_No response_

Additional Context

_No response_