[Bug] Anthropic API Error: Missing Tool Result Block

[fwends]

Bug Description API Error: 400 {"type":"error","error":{"type":"invalid_request_error","message":"messages.175: tool_use ids were found without tool_result blocks immediately after: toolu_015g5zBhDygcYYzT5aZSbDfA. Each tool_use block must have a corresponding tool_result block in the next message."},"request_id":"req_011CTbfG97rqTEntBzgaFmng"}

Environment Info

• Platform: darwin
• Terminal: vscode
• Version: 1.0.128
• Feedback ID: a094b15c-87a7-4ae4-9c50-6a85aaba8e15

Errors

[{"error":"Error: EISDIR: illegal operation on a directory, read\n    at Module.readFileSync (node:fs:433:20)\n    at Object.readFileSync (file:///Users/greg/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:719:16544)\n    at lBB (file:///Users/greg/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:3607:659)\n    at Object.call (file:///Users/greg/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:1712:952)\n    at call.next (<anonymous>)\n    at BO (file:///Users/greg/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:1163:30556)\n    at file:///Users/greg/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:1790:1328\n    at process.processTicksAndRejections (node:internal/process/task_queues:105:5)","timestamp":"2025-09-28T12:33:59.661Z"},{"error":"Error: EISDIR: illegal operation on a directory, read\n    at Module.readFileSync (node:fs:433:20)\n    at Object.readFileSync (file:///Users/greg/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:719:16544)\n    at lBB (file:///Users/greg/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:3607:659)\n    at Object.call (file:///Users/greg/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:1712:952)\n    at call.next (<anonymous>)\n    at BO (file:///Users/greg/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:1163:30556)\n    at file:///Users/greg/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:1790:1328\n    at process.processTicksAndRejections (node:internal/process/task_queues:105:5)","timestamp":"2025-09-28T12:33:59.693Z"},{"error":"Error: EISDIR: illegal operation on a directory, read\n    at Module.readFileSync (node:fs:433:20)\n    at Object.readFileSync (file:///Users/greg/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:719:16544)\n    at lBB (file:///Users/greg/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:3607:659)\n    at Object.call (file:///Users/greg/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:1712:952)\n    at call.next (<anonymous>)\n    at BO (file:///Users/greg/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:1163:30556)\n    at file:///Users/greg/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:1790:1328\n    at process.processTicksAndRejections (node:internal/process/task_queues:105:5)","timestamp":"2025-09-28T12:33:59.710Z"},{"error":"Error: Language not supported while highlighting code, falling back to markdown: \n    at AK (file:///Users/greg/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:1774:1183)\n    at file:///Users/greg/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:1774:911\n    at Array.map (<anonymous>)\n    at WJ (file:///Users/greg/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:1774:902)\n    at bJB (file:///Users/greg/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:2912:9380)\n    at KC (file:///Users/greg/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:34:19415)\n    at Mp (file:///Users/greg/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:36:42814)\n    at V9 (file:///Users/greg/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:36:38355)\n    at jh (file:///Users/greg/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:36:38283)\n    at LC (file:///Users/greg/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:36:38137)","timestamp":"2025-09-28T12:47:21.936Z"},{"error":"Error: Language not supported while highlighting code, falling back to markdown: \n    at AK (file:///Users/greg/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:1774:1183)\n    at file:///Users/greg/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:1774:2175\n    at Array.map (<anonymous>)\n    at AK (file:///Users/greg/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:1774:2146)\n    at file:///Users/greg/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:1774:2062\n    at Array.map (<anonymous>)\n    at AK (file:///Users/greg/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:1774:2051)\n    at file:///Users/greg/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:1774:911\n    at Array.map (<anonymous>)\n    at WJ (file:///Users/greg/.claude/local/node_modules/@anthropic-ai/claude-code/cli.js:1774:902)","timestamp":"2025-09-28T12:50:04.780Z"},{"error":"Error: Language not supported while highligh

Note: Error logs were truncated.

[fwends]

This is not a DUPLICATE it's 400 new error they happen all day for months you need to fix it rather than adding more gimicks

[levnikolaevich]

Bug Description API Error: 400 {"type":"error","error":{"type":"invalid_request_error","message":"messages.2: tool_use ids were found without tool_result blocks immediately after: toolu_01BQmW64bLmgxPbSia3FybMn. Each tool_use block must have a corresponding tool_result block in the next message."},"request_id":"req_011CTd5DZVXQ2TJBnzH3noVC"}

Environment Info Platform: win32 Terminal: cursor Version: 2.0.0 Feedback ID: aac94612-d0ba-4ef1-8e0f-e4f162199be1

[syaikhipin]

This is the bug while upgrading to v2

[tamamolis]

Bug Description API Error: 400 {"type":"error","error":{"type":"invalid_request_error","message":"messages.2: tool_use ids were found without tool_result blocks immediately after: toolu_01T9S2QnCtay9uMW6yFsfmwH. Each tool_use block must have a corresponding tool_result block in the next message."},"request_id":"req_011CTeCfXT3HCf32h2DsdDp2"}

Environment Info Platform: Ubuntu 24.04.2 LTS Terminal: ubuntu default terminal + pycharm Version: 2.0.1 Organization ID: e770deb4-a7e7-41d2-af79-330063fdce8d

[semikolon]

This is a disaster and an emergency. It's preventing me from doing real work. Occuring in pretty much every session I'm running. I have hooks active - I wonder if that's the culprit. Please somebody from the Claude Code team - reach out if you want help debugging this.

[github-actions[bot]]

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