Plan mode ExitPlanMode repeatedly rejected despite user approval

Description

When in plan mode, calling ExitPlanMode was rejected 4+ times in a row despite the user clicking "approve" / "accept" each time. The system returned a rejection error as if the user had denied the tool call.

Steps to Reproduce

1. Enter plan mode
2. Write a plan to the plan file
3. Call ExitPlanMode to request approval
4. User clicks approve/accept
5. System returns rejection error: "The user doesn't want to proceed with this tool use."
6. Repeats on subsequent attempts

Workaround

Making an edit to the plan file eventually triggered an automatic exit from plan mode, bypassing the ExitPlanMode tool entirely.

Environment

• Claude Code version: 2.1.72
• Model: claude-opus-4-6
• OS: macOS (Darwin 25.3.0)
• Shell: zsh

Expected Behavior

When the user approves the ExitPlanMode tool call, plan mode should exit and allow the conversation to proceed with edits and execution.

Actual Behavior

ExitPlanMode was rejected repeatedly (4+ times) despite user approval, trapping the conversation in plan mode until the workaround was discovered.