Fix Azure 40 character limit on tool_call_id

[colegottdank]

Summary

• Azure rejects tool_call_ids longer than 40 characters
• Adds truncateToolCallId function that deterministically shortens long IDs using a hash suffix
• Ensures the same truncated ID is used for both the assistant tool_call and the corresponding tool response
• Adds tests for long ID truncation

Test plan

• Unit tests pass for long ID truncation
• Unit tests pass for short ID preservation
• Test in production with Azure after deployment

🤖 Generated with Claude Code

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[claude]

Claude finished @colegottdank's task —— View job

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PR Review: Fix Azure 40 character limit on tool_call_id

Todo List:

• Read and analyze the changed files
• Review the truncateToolCallId implementation
• Examine test coverage and quality
• Check for potential issues and edge cases
• Provide structured feedback with confidence score

Analysis Complete

I've thoroughly reviewed both changed files. The implementation adds a truncateToolCallId function to handle Azure's 40-character limit on tool_call_ids, with comprehensive test coverage.

Score: 8/10 - Good implementation with minor suggestions for improvement

Detailed Review:

✅ Strengths:

1. Clear Problem Statement: Well-documented Azure limitation (40 char limit) with clear comments
2. Deterministic Approach: Same input produces same output, ensuring tool_calls match their responses
3. Comprehensive Test Coverage: Tests both long ID truncation and short ID preservation
4. Edge Case Handling: Properly handles missing IDs with fallback generation
5. Non-Breaking: Short IDs (<= 40 chars) are preserved unchanged

🔧 Minor Suggestions:

1. Hash Collision Risk: While unlikely, the current hash function could theoretically produce collisions. Consider using a more robust hash (crypto.createHash) for better uniqueness:

   import crypto from 'crypto';
   
   function truncateToolCallId(id: string): string {
     if (id.length <= AZURE_TOOL_CALL_ID_LIMIT) {
       return id;
     }
     // More robust hash to minimize collision risk
     const hash = crypto.createHash('sha256').update(id).digest('hex').slice(0, 8);
     const prefixLength = AZURE_TOOL_CALL_ID_LIMIT - hash.length - 1;
     return `${id.substring(0, prefixLength)}_${hash}`;
   }

2. Error Handling: Consider validation for empty/null IDs, though current fallback logic handles this adequately

3. Documentation: Could add JSDoc comment explaining the hash algorithm choice

🧪 Test Quality:

• Excellent test coverage with realistic scenarios
• Tests verify deterministic behavior (same input → same output)
• Covers both truncation and preservation cases
• Integration tests ensure end-to-end functionality

🚀 Performance:

• Minimal overhead - only processes long IDs
• Simple hash function is fast for typical ID lengths
• No unnecessary string operations

Suggestions Summary:

• Consider using crypto hash for better collision resistance (optional improvement)
• Add JSDoc documentation for the hash algorithm choice
• Current implementation is solid and ready to merge