[Bug] Anthropic API Error: Missing Tool Result Block

Resolved 💬 6 comments Opened Aug 24, 2025 by mattgodbolt Closed Jan 7, 2026

Bug Description
 API Error: 400 {"type":"error","error":{"type":"invalid_request_error","message":"messages.204: tool_use ids were found without tool_result blocks immediately after:

Environment Info

  • Platform: linux
  • Terminal: gnome-terminal
  • Version: 1.0.89
  • Feedback ID: 1034ecad-2776-40db-938a-aca91f204119

Errors

[{"error":"Error: Language not supported while highlighting code, falling back to markdown: asm\n    at <anonymous> (/$bunfs/root/claude:1609:795)\n    at useMemo (/$bunfs/root/claude:188:25924)\n    at e6 (/$bunfs/root/claude:1609:687)\n    at BF (/$bunfs/root/claude:188:19415)\n    at bb (/$bunfs/root/claude:190:42805)\n    at LY (/$bunfs/root/claude:190:38347)\n    at Zy (/$bunfs/root/claude:190:38275)\n    at $F (/$bunfs/root/claude:190:38129)\n    at TI (/$bunfs/root/claude:190:35208)\n    at JX (/$bunfs/root/claude:188:4842)","timestamp":"2025-08-24T15:50:19.699Z"},{"error":"Error: Language not supported while highlighting code, falling back to markdown: asm\n    at <anonymous> (/$bunfs/root/claude:1609:795)\n    at useMemo (/$bunfs/root/claude:188:25924)\n    at e6 (/$bunfs/root/claude:1609:687)\n    at BF (/$bunfs/root/claude:188:19415)\n    at bb (/$bunfs/root/claude:190:42805)\n    at LY (/$bunfs/root/claude:190:38347)\n    at Zy (/$bunfs/root/claude:190:38275)\n    at $F (/$bunfs/root/claude:190:38129)\n    at TI (/$bunfs/root/claude:190:35208)\n    at JX (/$bunfs/root/claude:188:4842)","timestamp":"2025-08-24T15:50:25.638Z"},{"error":"Error: Language not supported while highlighting code, falling back to markdown: \n    at U3 (/$bunfs/root/claude:1607:1192)\n    at <anonymous> (/$bunfs/root/claude:1607:2173)\n    at map (native:1:11)\n    at U3 (/$bunfs/root/claude:1607:2145)\n    at map (native:1:11)\n    at U3 (/$bunfs/root/claude:1607:2050)\n    at map (native:1:11)\n    at HK (/$bunfs/root/claude:1607:905)\n    at WGW (/$bunfs/root/claude:3025:8960)\n    at BF (/$bunfs/root/claude:188:19415)","timestamp":"2025-08-24T15:53:25.244Z"},{"error":"Error: Language not supported while highlighting code, falling back to markdown: \n    at U3 (/$bunfs/root/claude:1607:1192)\n    at <anonymous> (/$bunfs/root/claude:1607:2173)\n    at map (native:1:11)\n    at U3 (/$bunfs/root/claude:1607:2145)\n    at map (native:1:11)\n    at U3 (/$bunfs/root/claude:1607:2050)\n    at map (native:1:11)\n    at HK (/$bunfs/root/claude:1607:905)\n    at WGW (/$bunfs/root/claude:3025:8960)\n    at BF (/$bunfs/root/claude:188:19415)","timestamp":"2025-08-24T15:53:25.247Z"},{"error":"Error: Language not supported while highlighting code, falling back to markdown: asm\n    at <anonymous> (/$bunfs/root/claude:1609:795)\n    at useMemo (/$bunfs/root/claude:188:25924)\n    at e6 (/$bunfs/root/claude:1609:687)\n    at BF (/$bunfs/root/claude:188:19415)\n    at bb (/$bunfs/root/claude:190:42805)\n    at LY (/$bunfs/root/claude:190:38347)\n    at Zy (/$bunfs/root/claude:190:38275)\n    at $F (/$bunfs/root/claude:190:38129)\n    at TI (/$bunfs/root/claude:190:35208)\n    at JX (/$bunfs/root/claude:188:4842)","timestamp":"2025-08-24T15:57:25.638Z"},{"error":"Error: Language not supported while highlighting code, falling back to markdown: asm\n    at <anonymous> (/$bunfs/root/claude:1609:795)\n    at useMemo (/$bunfs/root/claude:188:25924)\n    at e6 (/$bunfs/root/claude:1609:687)\n    at BF (/$bunfs/root/claude:188:19415)\n    at bb (/$bunfs/root/claude:190:42805)\n    at LY (/$bunfs/root/claude:190:38347)\n    at Zy (/$bunfs/root/claude:190:38275)\n    at $F (/$bunfs/root/claude:190:38129)\n    at TI (/$bunfs/root/claude:190:35208)\n    at JX (/$bunfs/root/claude:188:4842)","timestamp":"2025-08-24T15:57:32.380Z"},{"error":"Error: Language not supported while highlighting code, falling back to markdown: assembly\n    at U3 (/$bunfs/root/claude:1607:1192)\n    at map (native:1:11)\n    at HK (/$bunfs/root/claude:1607:905)\n    at WGW (/$bunfs/root/claude:3025:8960)\n    at BF (/$bunfs/root/claude:188:19415)\n    at bb (/$bunfs/root/claude:190:42805)\n    at LY (/$bunfs/root/claude:190:38347)\n    at Zy (/$bunfs/root/claude:190:38275)\n    at $F (/$bunfs/root/claude:190:38129)\n    at TI (/$bunfs/root/claude:190:35208)","timestamp":"2025-08-24T15:58:16.986Z"},{"error":"Error: Language not supported while highlighting code, falling back to markdown: assembly\n    at U3 (/$bunfs/root/claude:1607:1192)\n    at map (native:1:11)\n    at HK (/$bunfs/root/claude:1607:905)\n    at WGW (/$bunfs/root/claude:3025:8960)\n    a

Note: Error logs were truncated.

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