Show HN: Recover bricked Claude Code sessions with "thinking blocks" error

[miteshashar]

I built a small open-source CLI to recover Claude Code sessions that get stuck on this error:

messages.N.content.M: thinking or redacted_thinking blocks in the latest assistant message cannot be modified

When this happens, `--resume` can keep failing and the session feels bricked.

The tool provides:

* diagnose SESSION_ID to find likely corruption points in session JSONL

* fix SESSION_ID for targeted repair (auto-backup before write)

* nuke SESSION_ID as fallback (strip all thinking/redacted_thinking blocks, also auto-backup)

Quick usage:

* claude-session-fix-thinking diagnose SESSION_ID

* claude-session-fix-thinking fix SESSION_ID

* claude --resume SESSION_ID

Repo: https://github.com/miteshashar/claude-code-thinking-blocks-f...

If you every got stuck due to this, you can use this script to resume your session.