Bug: Claude claims to save plan but saves incomplete/wrong content

Description

During a long session (~10,000 lines of conversation), I asked Claude to save a detailed implementation plan to a file. Claude confirmed it was saved.

After context summarization occurred (due to context window limits), the plan file contained only a small unrelated fragment (a minor CLAUDE.md sync task) instead of the full implementation plan we had worked on for hours.

Expected Behavior

When Claude confirms saving a plan to a file, the complete plan should actually be saved.

Actual Behavior

Claude said the plan was saved, but only a tiny fragment was written to the file. The rest of the plan was lost when context was summarized.

Impact

Full day of collaborative work lost. Claude cannot recover the plan from the summarized context because the summary doesn't contain the plan details.

Steps to Reproduce

1. Work on a complex, detailed plan over several hours (long conversation)
2. Ask Claude to save the plan to a file
3. Claude confirms it's saved
4. Continue working until context summarization occurs
5. Check the plan file - it contains incomplete/wrong content

Environment

• Claude Code CLI
• Model: claude-opus-4-5-20251101