Bug

During pre-compaction, the agent receives: 'Before compaction, write only durable/promotable facts to memory.'

The agent interprets this as overwriting MEMORY.md with a tiny snippet of 'durable facts', destroying the entire file (438 lines → 8 lines). This has happened multiple times.

Expected behavior

• Pre-compaction should NEVER overwrite workspace files
• If writing durable facts, it should APPEND, not replace
• Workspace files (MEMORY.md, SOUL.md, TOOLS.md) should be treated as read-only during compaction

Actual behavior

• Agent uses Write tool to replace MEMORY.md with a small snippet
• All rules, procedures, memory resolution order, project routing tables are lost
• User must manually restore from git

Workaround

Added a sacred header to MEMORY.md: 'NEVER OVERWRITE, NEVER COMPACT' with restore instructions. But this relies on the agent reading and obeying the header — which is the same agent that's about to compact.

Suggested fix

1. OpenClaw should snapshot workspace files before compaction
2. The pre-compaction prompt should explicitly say 'Do NOT overwrite or replace workspace files'
3. Or: make workspace files read-only during compaction (block Write tool for injected files)

Environment

• OpenClaw 2026.2.17 (e2dd827)
• Model: anthropic/claude-opus-4-6
• Also reproduced with xai/grok-4-1-fast-reasoning

Related

• Bug: Anthropic rejects history with dangling tool_use blocks after compaction #33621 (compaction orphans tool_use/tool_result pairs)