feat: Add nested argument formatting support

[Edison-A-N]

Description

This PR adds support for nested argument formatting in the Tool.to_code_prompt() method, providing comprehensive argument information to LLMs so they can generate correct nested arguments in a single attempt, reducing the need for error correction and reconfiguration cycles.

Changes

• Added format_nested_args() function: Supports recursive formatting of nested argument descriptions
• Supports up to 3 levels of nesting: With proper indentation to show hierarchical relationships
• Fully backward compatible: No impact on existing functionality

Testing

Added 3 new test cases:

• test_tool_to_code_prompt_with_nested_args: Tests basic nested argument formatting
• test_tool_to_code_prompt_with_deeply_nested_args: Tests deeply nested arguments (up to 3 levels)
• test_tool_to_code_prompt_with_mixed_nested_and_simple_args: Tests mixed argument types

All tests pass and code quality checks pass.

Example

Before:

# Complex nested arguments couldn't be properly formatted
inputs = {
    "config": {
        "type": "object",
        "description": "Configuration object",
        "properties": {
            "host": {"type": "string", "description": "Server host"},
            "port": {"type": "integer", "description": "Server port"},
        },
    }
}

After:

# Now provides complete nested structure for LLM understanding:
# Args:
#     config: Configuration object
#         host: Server host
#         port: Server port
# 
# This helps LLMs generate correct nested arguments like:
# {"config": {"host": "example.com", "port": 8080}}

[chahn]

Thanks a lot for this suggestion! I really like the direction you’ve taken with nested argument formatting.

I’d like to build on this and support a JSON schema to describe the input as well. If the input is a more complex object this approach would make a lot of sense, and would be a real improvement over the current implementation with a flat list of parameters.

We could do it the same way as we currently handle the output schema, to keep things consistent and flexible?