Claude Code / AI Coding Tools

Claude Code /clear Corrupts Message History — Orphaned tool_result Causes 400 API Error

Fix Claude Code /clear command that corrupts session history and triggers API 400 errors Includes evidence for Claude Code troubleshooting demand.

Category
AI Coding Tools
Error signature
/clear corrupts message history — orphaned tool_result causes 400 API error
Quick fix
Compare the failing environment with a known working setup, then change one configuration value at a time.
Updated

What this error means

/clear corrupts message history — orphaned tool_result causes 400 API error is a Claude Code failure pattern reported for developers trying to fix claude code /clear command that corrupts session history and triggers api 400 errors. Based on the imported evidence, treat this as a tool-specific troubleshooting page rather than a generic API error.

Why this happens

GitHub claude-code#59554 (2026-05-15). The /clear command leaves orphaned tool_result blocks in message history, causing subsequent API calls to fail with 400. Category mapping: Claude Code → AI Coding Tools.

Common causes

Quick fixes

  1. Confirm the exact error signature matches /clear corrupts message history — orphaned tool_result causes 400 API error.
  2. Check the Claude Code account, local tool state, and provider configuration involved in the failing workflow.
  3. Compare the failing environment with a known working setup, then change one configuration value at a time.

Platform/tool-specific checks

Step-by-step troubleshooting

  1. Capture the exact error message and the command, editor action, or request that triggered it.
  2. Check whether the failure is account/auth, quota/rate, model/provider, local runtime, or deployment configuration.
  3. Review the source evidence below and compare it with your environment.
  4. Apply one change at a time and rerun the smallest failing action.
  5. Keep the working fix documented for the team or deployment environment.

How to prevent it

Sources checked

Evidence note: GitHub claude-code#59554 (2026-05-15). The /clear command leaves orphaned tool_result blocks in message history, causing subsequent API calls to fail with 400. Category mapping: Claude Code → AI Coding Tools.

FAQ

What should I check first?

Start with the exact /clear corrupts message history — orphaned tool_result causes 400 API error text and the smallest action that reproduces it.

Can I ignore this error?

No. Treat it as a failed Claude Code workflow until the root cause is understood.

Is this guaranteed to have one fix?

No. The imported evidence supports the troubleshooting path above, but tool behavior can vary by account, plan, version, provider, and local configuration.

How do I know the fix worked?

Rerun the same command, editor action, or request. The fix is working when that action completes without /clear corrupts message history — orphaned tool_result causes 400 API error.