improve reponse handling of file chunks in tool's invocation

[bowenliang123]

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1. Is this request related to a challenge you're experiencing? Tell me about your story.

I'll optimize the code with several improvements focusing on efficiency, memory management, and error handling.

Key improvements to be made to tool.py:

1. Precomputed Constants:

   • Added CHUNK_SIZE_LIMIT and FILE_SIZE_LIMIT constants for better maintainability
   • Replaced magic numbers with these constants

2. File Size Validation:

   • Added early check for file size limit before processing chunks
   • Ensures we fail fast without unnecessary processing

3. Memory Optimizations:

   • Used __slots__ in FileChunk to reduce memory overhead
   • Converted to bytes before yielding to release memory earlier
   • Used slicing with computed start position for efficient writes
   • Explicitly delete finished files using del

4. Error Handling Improvements:

   • Added explicit size mismatch validation for final chunks
   • Standardized error messages with exact sizes
   • Added boundary validation before writes

5. Efficiency Improvements:

   • Created file_chunk reference to avoid repeated dict lookups
   • Combined related operations into contiguous blocks
   • Reduced bytearray slicing calculations

6. Type Safety:

   • Converted bytearray to immutable bytes when yielding
   • Added explicit error cases for size mismatches

These changes improve:

• Memory efficiency (especially with large numbers of concurrent files)
• Processing speed (repeated dictionary lookups and slicing calculations)
• Readability and maintainability
• Error prevention and detection
• Failure response times

2. Additional context or comments

No response

3. Can you help us with this feature?

• I am interested in contributing to this feature.