[RFE] TodoWriter needs an "update" mode?

Environment

• Platform (select one):
• [ ] Anthropic API
• [ ] AWS Bedrock
• [ ] Google Vertex AI
• [X] Other: Max subscription
• Claude CLI version: 1.0.102 (Claude Code)
• Operating System: MacOS desktop -> VSCode -> SSH session on Ubuntu -> Dev Container on Ubuntu
• Terminal: VSCode

Bug Description

When Claude revises its todo list, it almost always simplifies it / drops things / etc.

Steps to Reproduce

1. Go into planning mode
2. Ask it to create a detailed todo list (my go-to is to say something like: "Before you start, create a detailed TodoWriter todo list (with all key contingencies, investigation, root cause analysis, look-back, documentation, etc steps identified) - keep in mind that as you go along, this may be a key source of important context for you to remind yourself of everything that needs to be taken into account.")
3. At it goes along, ask it to revise a portion of the todo list.

Expected Behavior

The intended part of the todo list is revised; everything else is unchanged.

Actual Behavior

Almost always: the whole list is greatly simplified with important steps forgotten.

Additional Context

For a large list, this would also significantly reduce output token use if Claude does not have to repeat the steps it's not modifying. That said, I might just be completely misdiagnosing this - reporting based on my recollection of my experiences without explicitly trying to reproduce, sorry.