[Bug] Anthropic API Error: Missing corresponding tool_use block for tool_result

Open 💬 0 comments Opened Jun 21, 2026 by dcrtslnr

Bug Description
Conversation was paused mid way and when i try to continue i get an api error - API Error: 400 messages.9.content.0: unexpected tool_use_id found in advisor_tool_result blocks: srvtoolu_01MvcfFiGRA7kPxmehgzKna7. Each advisor_tool_result block must have a corresponding server_tool_use block before it.

Environment Info

  • Platform: darwin
  • Terminal: Apple_Terminal
  • Version: 2.1.183
  • Feedback ID: 224c90aa-ba15-4158-bdc1-728a675e927f

Errors

[{"error":"Error: 400 {\"type\":\"error\",\"error\":{\"type\":\"invalid_request_error\",\"message\":\"messages.9.content.0: unexpected `tool_use_id` found in `advisor_tool_result` blocks: srvtoolu_01MvcfFiGRA7kPxmehgzKna7. Each `advisor_tool_result` block must have a corresponding `server_tool_use` block before it.\"},\"request_id\":\"req_011CcFrRTuPpByjqc1RFQQ2A\"}\n    at generate (/$bunfs/root/src/entrypoints/cli.js:12:68924)\n    at makeRequest (/$bunfs/root/src/entrypoints/cli.js:52:7688)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-06-21T05:28:27.818Z"},{"error":"Error: 400 {\"type\":\"error\",\"error\":{\"type\":\"invalid_request_error\",\"message\":\"messages.9.content.0: unexpected `tool_use_id` found in `advisor_tool_result` blocks: srvtoolu_01MvcfFiGRA7kPxmehgzKna7. Each `advisor_tool_result` block must have a corresponding `server_tool_use` block before it.\"},\"request_id\":\"req_011CcFrSNHLYDRUu6j5QuyK8\"}\n    at generate (/$bunfs/root/src/entrypoints/cli.js:12:68924)\n    at makeRequest (/$bunfs/root/src/entrypoints/cli.js:52:7688)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-06-21T05:28:40.058Z"},{"error":"Error: 400 {\"type\":\"error\",\"error\":{\"type\":\"invalid_request_error\",\"message\":\"messages.9.content.0: unexpected `tool_use_id` found in `advisor_tool_result` blocks: srvtoolu_01MvcfFiGRA7kPxmehgzKna7. Each `advisor_tool_result` block must have a corresponding `server_tool_use` block before it.\"},\"request_id\":\"req_011CcFrU85sJnWneMMVm5wSv\"}\n    at generate (/$bunfs/root/src/entrypoints/cli.js:12:68924)\n    at makeRequest (/$bunfs/root/src/entrypoints/cli.js:52:7688)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-06-21T05:29:03.920Z"},{"error":"Error: 400 {\"type\":\"error\",\"error\":{\"type\":\"invalid_request_error\",\"message\":\"messages.9.content.0: unexpected `tool_use_id` found in `advisor_tool_result` blocks: srvtoolu_01MvcfFiGRA7kPxmehgzKna7. Each `advisor_tool_result` block must have a corresponding `server_tool_use` block before it.\"},\"request_id\":\"req_011CcFrXCFyQnJjixDZpEWiS\"}\n    at generate (/$bunfs/root/src/entrypoints/cli.js:12:68924)\n    at makeRequest (/$bunfs/root/src/entrypoints/cli.js:52:7688)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-06-21T05:29:45.548Z"}]

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