openclaw - 💡(How to fix) Fix Session corruption from orphaned tool_result blocks survives restart (overload/timeout interruption) [1 comments, 1 participants]

When a session is interrupted mid-tool-call (overload, timeout, rate limit), the conversation history can end up with orphaned tool_result blocks that have no matching tool_use before them. On the next API call, Anthropic rejects the malformed history (e.g. messages.36 validation error), and the session is effectively dead until manually nuked.

• session-transcript-repair.js → repairToolUseResultPairing() drops orphans, deduplicates, inserts synthetic error results

TL;DR

Run the repairToolUseResultPairing() function on session file load to prevent corruption and make sessions self-healing.

Guidance

• Modify the session loading logic to run repairToolUseResultPairing() on the loaded session data to detect and fix any orphaned tool_result blocks.
• Immediately rewrite the session file with the repaired data to ensure consistency across restarts.
• Consider adding a check to prevent compaction from running while a tool call is in flight to avoid producing a compacted history with broken tool_use/tool_result pairing.
• Review the transcript-sanitize.js and sanitizeSessionHistory() functions to ensure they are correctly sanitizing the session history before every API call.

Example

No explicit code example is provided, but the repairToolUseResultPairing() function in session-transcript-repair.js can be used as a reference for implementing the repair logic on session file load.

Notes

This solution assumes that the repairToolUseResultPairing() function is correctly implemented and effective in repairing corrupted session histories. Additionally, this fix may not address all possible corruption scenarios, and further testing and validation may be necessary to ensure its effectiveness.

Recommendation

Apply the suggested fix by running repairToolUseResultPairing() on session file load, as this will help prevent corruption and make sessions self-healing, reducing the need for manual intervention.