claude-code - 💡(How to fix) Fix [Bug] Anthropic API Error: 400 Tool Use Concurrency Issue from claude code (iTerm2 CLI) [1 participants]

[ { "error": "Error: EISDIR: illegal operation on a directory, read '/Users/<USER>/workspace/<ORG_TOOLS>/<TICKET>-local-prod-mgmt'\n at WKH (/$bunfs/root/src/entrypoints/cli.js:1561:144)\n at processTicksAndRejections (native:7:39)", "timestamp": "2026-04-27T05:04:58.728Z" }, { "error": "Error: File does not exist. Note: your current working directory is /Users/<USER>/workspace/<ORG_TOOLS>/<TICKET>-local-prod-mgmt.\n at call (/$bunfs/root/src/entrypoints/cli.js:4727:7630)\n at processTicksAndRejections (native:7:39)", "timestamp": "2026-04-27T05:07:09.861Z" }, { "error": "Error: ENOENT: no such file or directory, scandir '/Users/<USER>/Users/<USER>/workspace/<SERVICE_REPO>'\n at async Hs4 (/$bunfs/root/src/entrypoints/cli.js:621:11190)\n at async kK9 (/$bunfs/root/src/entrypoints/cli.js:621:11692)\n at async <anonymous> (/$bunfs/root/src/entrypoints/cli.js:8268:14295)", "timestamp": "2026-04-27T06:06:21.216Z" }, { "error": "Error: ENOENT: no such file or directory, scandir '/Users/<USER>/Users/<USER>/workspace/<SERVICE_REPO>'\n at async Hs4 (/$bunfs/root/src/entrypoints/cli.js:621:11190)\n at async kK9 (/$bunfs/root/src/entrypoints/cli.js:621:11692)\n at async <anonymous> (/$bunfs/root/src/entrypoints/cli.js:8268:14295)", "timestamp": "2026-04-27T06:06:21.281Z" }, { "error": "Error: ENOENT: no such file or directory, scandir '/Users/<USER>/Users/<USER>/workspace/<SERVICE_REPO>'\n at async Hs4 (/$bunfs/root/src/entrypoints/cli.js:621:11190)\n at async kK9 (/$bunfs/root/src/entrypoints/cli.js:621:11692)\n at async <anonymous> (/$bunfs/root/src/entrypoints/cli.js:8268:14295)", "timestamp": "2026-04-27T06:06:32.666Z" }, { "error": "Error: 400 {"type":"error","error":{"type":"invalid_request_error","message":"messages.<N>: tool_use ids were found without tool_result blocks immediately after: <TOOL_USE_ID>. Each tool_use block must have a corresponding tool_result block in the next message."},"request_id":"<REQUEST_ID>"}\n at generate (/$bunfs/root/src/entrypoints/cli.js:11:52701)\n at makeRequest (/$bunfs/root/src/entrypoints/cli.js:50:4943)\n at processTicksAndRejections (native:7:39)", "timestamp": "2026-04-27T06:07:30.676Z" }, { "error": "Error: API Error: 400 due to tool use concurrency issues. Run /rewind to recover the conversation.\n at bf7 (/$bunfs/root/src/entrypoints/cli.js:4732:1096)\n at async <anonymous> (/$bunfs/root/src/entrypoints/cli.js:8402:15580)\n at async l (/$bunfs/root/src/entrypoints/cli.js:8203:552)\n at processTicksAndRejections (native:7:39)", "timestamp": "2026-04-27T06:08:11.563Z" } ]

TL;DR

Run the /rewind command to recover the conversation and resolve the API Error 400 due to tool use concurrency issues.

Guidance

• The error messages indicate issues with file directories and concurrency, suggesting that the system is experiencing problems with simultaneous tool usage.
• The specific error "API Error: 400 due to tool use concurrency issues" points towards a synchronization problem that can be mitigated by running the /rewind command as suggested.
• Verify that the /rewind command successfully recovers the conversation by checking for any further error messages after executing the command.
• If issues persist, consider checking the file system for any inconsistencies or permissions problems that might be contributing to the errors.

Notes

The provided information does not specify the exact cause of the concurrency issues, so the effectiveness of the /rewind command may vary. Additionally, the truncated content might hide other relevant details.

Recommendation

Apply the workaround by running the /rewind command as it is explicitly suggested by the error message as a recovery method for the conversation.