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[Bug] Anthropic API Error: Unresolved Tool Use Block Requires Tool Result #6567

@johnburbridge

Description

@johnburbridge

Bug Description
I'm stuck. Everything was fine but I noticed I was approaching 10% of my session's context window so decided to take a deliberate step (as I've done many times before) to summarize what had been accomplished and ran into this:

> Let's prepare for context compaction by creating a comprehensive summary of where we are.
  ⎿  API Error: 400 {"type":"error","error":{"type":"invalid_request_error","message":"messages.56: `tool_use` ids were found without `tool_result` blocks immediately after:
     toolu_01XghcaW1dGMcThFqjNVoxKn. Each `tool_use` block must have a corresponding `tool_result` block in the next message."},"request_id":"req_011CSVhf2NgPmHcjeLsmAfXc"}

> Let's prepare for context compaction by creating a comprehensive summary of where we are.
  ⎿  API Error: 400 {"type":"error","error":{"type":"invalid_request_error","message":"messages.56: `tool_use` ids were found without `tool_result` blocks immediately after:
     toolu_01XghcaW1dGMcThFqjNVoxKn. Each `tool_use` block must have a corresponding `tool_result` block in the next message."},"request_id":"req_011CSVhgQduxUQjbPryKrMud"}

> Let's prepare for context compaction by creating a comprehensive summary of where we are.
  ⎿  API Error: 400 {"type":"error","error":{"type":"invalid_request_error","message":"messages.56: `tool_use` ids were found without `tool_result` blocks immediately after:
     toolu_01XghcaW1dGMcThFqjNVoxKn. Each `tool_use` block must have a corresponding `tool_result` block in the next message."},"request_id":"req_011CSVhinRQLRWGJ9dHN1Crz"}

> /doctor
  ⎿  (no content)

> Let's prepare for context compaction by creating a comprehensive summary of where we are.
  ⎿  API Error: 400 {"type":"error","error":{"type":"invalid_request_error","message":"messages.56: `tool_use` ids were found without `tool_result` blocks immediately after:
     toolu_01XghcaW1dGMcThFqjNVoxKn. Each `tool_use` block must have a corresponding `tool_result` block in the next message."},"request_id":"req_011CSVhtwWP6kHv2biiSU4YY"}

Running doctor didn't help. Not sure what I should do next?

Environment Info

  • Platform: darwin
  • Terminal: iTerm.app
  • Version: 1.0.92
  • Feedback ID:

Errors

[{"error":"Error: Tool mcp__linear__get_issue not found\n    at GgB (file:///Users/jburbridge/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:3167:4437)\n    at $z (file:///Users/jburbridge/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:330:19415)\n    at Ic (file:///Users/jburbridge/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:332:42814)\n    at eQ (file:///Users/jburbridge/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:332:38355)\n    at _b (file:///Users/jburbridge/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:332:38283)\n    at jz (file:///Users/jburbridge/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:332:38137)\n    at kH (file:///Users/jburbridge/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:332:35216)\n    at e6 (file:///Users/jburbridge/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:330:4841)\n    at A5 (file:///Users/jburbridge/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:332:32461)\n    at A.Q.updateContainer (file:///Users/jburbridge/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:336:1837)","timestamp":"2025-08-26T04:37:57.730Z"},{"error":"Error: Tool mcp__linear__list_issues not found\n    at GgB (file:///Users/jburbridge/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:3167:4437)\n    at $z (file:///Users/jburbridge/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:330:19415)\n    at Ic (file:///Users/jburbridge/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:332:42814)\n    at eQ (file:///Users/jburbridge/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:332:38355)\n    at _b (file:///Users/jburbridge/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:332:38283)\n    at jz (file:///Users/jburbridge/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:332:38137)\n    at kH (file:///Users/jburbridge/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:332:35216)\n    at e6 (file:///Users/jburbridge/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:330:4841)\n    at A5 (file:///Users/jburbridge/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:332:32461)\n    at A.Q.updateContainer (file:///Users/jburbridge/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:336:1837)","timestamp":"2025-08-26T04:37:57.734Z"},{"error":"Error: Tool mcp__linear__list_issues not found\n    at GgB (file:///Users/jburbridge/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:3167:4437)\n    at $z (file:///Users/jburbridge/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:330:19415)\n    at 

Note: Error logs were truncated.

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