JSON parsing errors in tool call arguments

[ahamza360]

LLMs occasionally generate malformed/truncated JSON for tool call arguments, resulting in "JSON parsing failed" errors. This issue tracks the fix for this problem.

Related PR: #23064

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What needs to be fixed:

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This issue might be a duplicate of existing issues. Please check:

• Tool call arguments may contain invalid JSON #17750: Tool call arguments may contain invalid JSON — same root cause (LLM-generated malformed/truncated JSON in tool call arguments, same error message pattern)
• retry invalid tool-call diff / malformed tool input instead of aborting #15906: retry invalid tool-call diff / malformed tool input instead of aborting — covers the same JSON parsing failed error and proposes retry/repair behavior
• Truncated tool calls are misclassified and unrecoverable (finishReason: length + repairToolCall + doom loop) #18108: Truncated tool calls are misclassified and unrecoverable — related issue about handling truncated/malformed tool call responses

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This issue has been automatically closed because it was not updated to meet our contributing guidelines within the 2-hour window.

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