[BUG] Plan Mode Regression in 2.0.51+

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?

Feedback: Plan Mode Regression in 2.0.51+

Product: Claude Code
Version: 2.0.51+ (current: 2.0.58)
Feature: Plan Mode (/plan)

---

Summary

The Plan Mode redesign in 2.0.51 removed the interactive exploration capability that was previously its core value. It now functions as a rigid implementation-plan pipeline, eliminating the space for discussion and reflection before committing to a plan.

---

Previous Behavior (< 2.0.51)

• Plan mode was an interactive space for exploration and discussion
• Users could reflect, ask questions, explore options with Claude
• No pressure to produce a deliverable
• User controlled when/if to create an implementation plan
• Supported iterative thinking: explore → discuss → refine → then plan

Current Behavior (≥ 2.0.51)

• Plan mode is now a 5-phase pipeline with forced progression:

1. Launch Explore agents
2. Launch Plan agents
3. Review
4. Write final plan to file
5. Call ExitPlanMode

• System prompt enforces: "your turn should only end with either asking the user a question or calling ExitPlanMode"
• Claude is pushed to produce a written plan regardless of user intent
• No space for open-ended exploration or discussion
• User's exploratory questions are treated as implementation requests

---

Impact

Use case broken: "I want to explore and discuss options before deciding on an approach"

Example from my session:

• I asked: "Let's explore tracing and evaluation options for my project"
• Expected: Claude researches Langfuse, RAGAS, DeepEval, discusses trade-offs with me
• Actual: Claude immediately launched Plan agents and produced a full implementation plan I didn't ask for

The new design assumes entering Plan Mode = wanting an implementation plan. This removes the valuable thinking space that differentiated Plan Mode from normal mode.

---

Suggested Fix

Option A: Add an "Exploration Phase" before the planning pipeline

• Allow users to explicitly signal when they're ready to move from exploration to planning
• Don't auto-launch Plan agents until user confirms

Option B: Create separate modes

• explore mode - Interactive discussion, research, no deliverable pressure
• plan mode - Current implementation-plan pipeline

Option C: Make the pipeline phases optional

• Let users stay in Phase 1 (exploration) indefinitely
• Only progress to planning phases when user explicitly requests

---

Environment

• Claude Code version: 2.0.58
• Model: Opus 4.5
• OS: macOS Darwin 25.1.0

---

Priority: High - This is a workflow regression that forces users out of their preferred interaction pattern.

What Should Happen?

Previous Behavior (< 2.0.51)

• Plan mode was an interactive space for exploration and discussion
• Users could reflect, ask questions, explore options with Claude
• No pressure to produce a deliverable
• User controlled when/if to create an implementation plan
• Supported iterative thinking: explore → discuss → refine → then plan

Error Messages/Logs

Steps to Reproduce

Example from my session:

• I asked: "Let's explore tracing and evaluation options for my project"
• Expected: Claude researches Langfuse, RAGAS, DeepEval, discusses trade-offs with me
• Actual: Claude immediately launched Plan agents and produced a full implementation plan I didn't ask for

The new design assumes entering Plan Mode = wanting an implementation plan. This removes the valuable thinking space that differentiated Plan Mode from normal mode.

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

2.0.50

Claude Code Version

2.0.58

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_