[Bug] Anthropic API Error: Tool use concurrency conflict in tasks

Bug Description
I am getting this a lot when using the new tasks

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

Environment Info

• Platform: darwin
• Terminal: iTerm.app
• Version: 2.1.19
• Feedback ID: 26a5a6d8-afa5-407f-ba43-c95b27c8eddc

Errors

[{"error":"Error: ENOENT: no such file or directory, scandir '/Library/Application Support/ClaudeCode/.claude/skills'\n    at readdirSync (unknown)\n    at <anonymous> (/$bunfs/root/claude:12:1903)\n    at mW (/$bunfs/root/claude:11:35435)\n    at readdirSync (/$bunfs/root/claude:12:1864)\n    at ILR (/$bunfs/root/claude:2215:380)\n    at ILR (/$bunfs/root/claude:2215:1350)\n    at <anonymous> (/$bunfs/root/claude:2215:4440)\n    at <anonymous> (/$bunfs/root/claude:2215:5171)\n    at A (/$bunfs/root/claude:11:7259)\n    at FZ8 (/$bunfs/root/claude:4862:4342)","timestamp":"2026-01-26T15:15:10.234Z"},{"error":"Error: NON-FATAL: Lock acquisition failed for /Users/cgibbons/.local/share/claude/versions/2.1.19 (expected in multi-process scenarios)\n    at BUR (/$bunfs/root/claude:4003:2091)\n    at YkA (/$bunfs/root/claude:4003:1202)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-01-26T15:15:10.268Z"},{"error":"Error: ENOENT: no such file or directory, scandir '/Library/Application Support/ClaudeCode/.claude/skills'\n    at readdirSync (unknown)\n    at <anonymous> (/$bunfs/root/claude:12:1903)\n    at mW (/$bunfs/root/claude:11:35435)\n    at readdirSync (/$bunfs/root/claude:12:1864)\n    at ILR (/$bunfs/root/claude:2215:380)\n    at ILR (/$bunfs/root/claude:2215:1350)\n    at <anonymous> (/$bunfs/root/claude:2215:4440)\n    at <anonymous> (/$bunfs/root/claude:2215:5171)\n    at A (/$bunfs/root/claude:11:7259)\n    at FZ8 (/$bunfs/root/claude:4862:4342)","timestamp":"2026-01-26T15:15:15.931Z"},{"error":"Error: 400 {\"type\":\"error\",\"error\":{\"type\":\"invalid_request_error\",\"message\":\"messages.17.content.18: `thinking` or `redacted_thinking` blocks in the latest assistant message cannot be modified. These blocks must remain as they were in the original response.\"},\"request_id\":\"req_011CXWDaymQEcGxVALyH7bJZ\"}\n    at generate (/$bunfs/root/claude:144:37450)\n    at makeRequest (/$bunfs/root/claude:161:5435)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-01-26T15:22:01.534Z"}]